What is the name of the method of performing a plumbing operation. General information about locksmith work. Topic. Basics of metalworking

Markup.

Locksmith's workplace.

Topic. Basics of locksmith processing.

(independent study)

Questions:

1. locksmith work - this is the manual processing of materials, the fitting of parts, the assembly and repair of various mechanisms and machines.

workplace they call a part of the production area with all the equipment, tools and materials located on it, which are used by a worker or a team of workers to complete a production task.

The workplace should occupy the area necessary for the rational placement of equipment on it and the free movement of the locksmith during work. The distance from the workbench and racks to the locksmith should be such that he can use mainly the movement of his hands and, if possible, avoid turning and bending the body. The workplace should have good individual lighting.

locksmith workbench(Fig. 48) - the main equipment of the workplace. It is a stable metal or wooden table, the lid (tabletop) of which is made of boards 50 ... 60 mm thick of hardwood and covered with sheet iron. Single workbenches are the most convenient and common, since on multi-seat workbenches, when several people work at the same time, the quality of precision work is reduced.

Rice. 48 Single locksmith workbench:

1 - frame; 2 - countertop; 3 - vice; 4 - protective screen; 5 - tablet for drawings; 6 - lamp; 7 - shelf for tools; 8 - tablet for a working tool; 9 - boxes; 10 - shelves; 11 - seat

The workbench contains the tools necessary to complete the task. The drawings are placed on the tablet, and the measuring tools are placed on the shelves.

Under the tabletop of the workbench are drawers, divided into a number of cells for storing tools and documentation.

To fix the workpieces, a vise is installed on the workbench. Depending on the nature of the work, parallel, chair and hand vices are used. The most widespread are parallel swivel and non-swivel vices, in which the jaws remain parallel during divorce. The rotary part of the vise is connected to the base with a center bolt, around which it can be rotated at any angle and fixed in the required position with the help of a handle. To increase the service life of the vise, steel overhead sponges are attached to the working parts of the jaws. Chair vise is rarely used, only for work related to shock loading (when cutting, riveting, etc.). When processing small parts, use a hand vise.

The choice of the height of the vice according to the height of the worker and the rational placement of the tool on the workbench contribute to a better formation of skills, an increase in labor productivity and reduce fatigue.

When choosing the height of the vise installation, the left hand bent at the elbow is placed on the vise jaws so that the ends of the straightened fingers of the hand touch the chin. Tools and devices are arranged so that it is convenient to take them with the appropriate hand: what is taken with the right hand - hold on the right, what is taken with the left - on the left.

A protective screen made of metal mesh or durable plexiglass is installed on the workbench to retain pieces of metal that fly off during cutting.

Blanks, finished parts and fixtures are placed on racks installed in the area allotted for them.

2. markup - the operation of applying lines (rises) to the workpiece, defining (according to the drawing) the contours of the part and the places to be processed. Marking is used for individual and small-scale production.

Marking is carried out on marking plates cast from gray cast iron, aged and precisely machined.

Lines (risks) with a planar marking are applied with a scriber, with a spatial marking, with a scriber fixed in the thickness gauge collar. Scribers are made of steel grades U10 and U12, their working ends are hardened and sharpened sharply.

Kerner is intended for drawing recesses (cores) on previously marked lines. It is made from steel grades U7, U7A, U8 and U8A.

Marking compass is used to draw circles, divide angles and apply linear dimensions to the workpiece.

3. The main types of plumbing operations.

felling- a locksmith operation, during which excess metal layers are removed from the workpiece with a cutting and impact tool, grooves and grooves are cut out, or the workpiece is divided into parts. The cutting tool is a chisel, a cross-cutting tool, and a hammer is a percussion tool.

chisel cut metal and cut off burrs. It has a working middle and impact parts. The working part of the chisel is wedge-shaped with a cutting part sharpened at a certain angle depending on the hardness of the metal being processed. The chisel is held for the middle part during cutting, the impact part (head) tapers upward and is rounded to center the blow.

Kreutzmeisel they cut out grooves and narrow grooves, and for cutting profile grooves they use special crosscuts - “grooves”, which differ in the shape of the cutting edge.

Chisels, crosscuts and groovers are made of steel U7, U7A, U8 and U8A. Their working and shock parts are hardened and released.

Locksmith hammers have a square or round shock part - a striker. The end of the hammer opposite the striker, which has the shape of a rounded wedge, is called the toe. It is used for riveting, straightening, etc.

Hammers are made of steel grades 50, 50X, U7 and U8. The working parts of the hammer (striker and toe) are hardened and released.

cutting is the operation of separating metals and other materials into parts. Depending on the shape and size of the blanks, cutting is carried out with a hand saw, hand or lever scissors.

Hand saw consists of a steel solid or sliding frame and a hacksaw blade, which is inserted into the slots of the heads and secured with pins. A handle is fixed on the shank of the fixed head. A movable head with a screw and a wing nut is used to tension the hacksaw blade. The cutting part of the hacksaw is a hacksaw blade (a narrow and thin plate with teeth on one of the ribs) made of steel grades U10A, 9XC, P9, P18 and hardened. Hacksaw blades are used with a length (distance between holes) of 250-300 mm. The teeth of the blade are spread (bend) so that the width of the cut is slightly greater than the thickness of the blade.

Metal dressing- an operation in which irregularities, dents, curvature, warpage, waviness and other defects in materials, workpieces and parts are eliminated. Editing in most cases is a preparatory operation. Straightening has the same purpose as straightening, but defects are corrected in hardened parts.

bending widely used to give blanks a certain shape in the manufacture of parts. For manual straightening and bending, correct plates, straightening headstocks, anvils, vices, mandrels, sledgehammers, metal and wooden hammers (mallets) and special devices are used.

Klepka- locksmith operation of joining two or more parts with rivets. Rivet connections are one-piece and are used in the manufacture of various metal structures.

Rivets are metal cylindrical rods with pre-planted heads. They are made from carbon steels, alloyed steels 09G2 and Kh18N9T, non-ferrous metals and alloys MZ, L62, AD1 and D18P. Several types of rivets are used: with a semicircular high or low head, with a flat head, with a countersunk and semi-secret head, explosive, two-chamber. Rivets with semicircular and countersunk heads are most often used. The second (closing) head of the rivet is planted during riveting.

The riveting is performed in a cold or hot (if the rivet diameter is more than 10 mm) state. The advantage of hot riveting is that the rod fills the holes in the parts to be joined better, and when cooled, the rivet pulls them together better. When riveting in a hot state, the diameter of the rivet should be 0.5 ... 1 mm smaller than the hole, and in a cold state, by 0.1 mm.

Manual riveting is performed with a hammer, its mass is chosen depending on the diameter of the rivet, for example, for rivets with a diameter of 3 ... 3.5 mm, a hammer weighing 200 g is required.

filing- a locksmith operation, in which a layer of metal is cut off from the surface of the part with files to obtain the required shape, size and surface roughness, to fit parts during assembly and prepare edges for welding.

Files are steel (steel grades U13, U13A; ShKh13 and 13Kh) hardened bars of various profiles with teeth cut on the working surfaces. The teeth of the file, having the shape of a sharpened wedge in cross section, cut off layers of metal in the form of chips (sawdust) from the workpiece.

Files are made with single and double (cross) notch. According to their purpose, files are divided into groups: general purpose, special purpose, needle files, rasps, machine files. Depending on the number of notches per 1 cm of length, the files are divided into the following numbers: 0 and 1 - bastard, 2 and 3 - personal, 4 and 5 - velvet. Bastard files are used for rough filing, when it is necessary to remove a metal layer of more than 0.3 mm, the accuracy of their processing is low. For fine filing with an accuracy of 0.02 and 0.05 mm, personal files are used, the thickness of the metal layer removed by them is not higher than 0.02 and 0.06 mm. Velvet files are designed for final processing of parts with an accuracy of 0.01 ... 0.005 mm, the thickness of the metal layer removed by them is 0.01 ... 0.03 mm.

Files with a notch in the form of individual (point) teeth are called rasps. They are used for filing viscous and soft materials (babbitt, wood, etc.).

For processing small surfaces and finishing work, needle files are used. Files are available in lengths of 100, 125, 150, 200, 250, 300, 350 and 400 mm. According to the shape of the cross section, files are produced in eight types of flat

(pointed and blunt), square, round, semicircular, trihedral, rhombic and hacksaw.

In the process of obtaining and processing holes, drills are used, countersinks, countersinks and reamers.

In locksmithing, in some cases, holes are drilled and machined manually. In this case, the tool is rotated with manual, electric and pneumatic drills, as well as with the help of ratchets. With manual countersinking and reaming, the tool is fixed in the knob and rotated, and the workpiece (just like when drilling) is clamped in a vice or other devices. It should be remembered that the work of a blunt or incorrectly sharpened tool on faulty equipment and fixtures causes tool breakage and defective parts.

Threaded connection- a reliable type of fastening of machine parts. It allows easy assembly, adjustment, disassembly.

A helical groove cut on the outer or inner cylindrical surface forms an external or internal thread, respectively. A thread profile is a section of its coil by a plane passing through the axis of the cylinder on which the thread is cut. Thread (coil) called the part of the thread formed during one complete revolution of the profile. Profile angle thread is called the angle enclosed between the sides of the thread profile. profile cavity- the section connecting the sides of the groove. thread pitch- the distance between two similar points of adjacent turns, measured parallel to the axis of the thread.

According to the thread profile, there are cylindrical triangular, conical triangular, rectangular, trapezoidal, persistent and round.

In mechanical engineering, three triangular thread systems are common: metric, inch and pipe. Metric thread has a profile angle of 60 °, is characterized by a pitch and a diameter expressed in the metric system of measures - millimeters. Inch thread has a profile angle of 55 °, the outer diameter is measured in inches (1 "is equal to 25.4 mm), the pitch is characterized by the number of threads per 1", rarely used. Pipe thread has an inch thread profile and is characterized by the number of threads 1", used to connect pipes.

Threading tools are taps and dies. They are made from steels U10A, U11A, U12A, 9XC and P18.

For threading holes, a set of two or three taps with different diameters of the working part (rough, medium and finish) is used. To distinguish the tap on its shank, circular risks are applied. The fine tap has three circular risks and is used for fine threading, as it has a full profile of the cutting part.

For cutting external threads, several types of dies are used: round, square, hexagonal and sliding prismatic.

The diameter of the drill to obtain a hole for a thread is determined from the tables or (with sufficient accuracy) by subtracting its pitch from the diameter of the thread. The diameter of the rod should be equal to the outer diameter of the thread being cut, but usually it is taken less by 0.3 ... 0.4 mm to obtain a good thread quality.

Emulsion, kerosene, machine oil are used as lubricants.

Shabreniy the operation of scraping thin layers of metal from the surface of a part with a cutting tool is called - scraper. This is the final processing of precision surfaces (machine guides, control plates, plain bearings, etc.) to ensure tight mating. Scrapers are made of U10 and U12A steels, their cutting ends are hardened without tempering to a hardness of HRC 64...66.

Scrapers are divided: by design (one-piece and with insert plates); by the number of cutting ends (one-sided and two-sided); according to the shape of the cutting part (flat, three-, four-sided and shaped).

For scraping planes, a flat scraper with a straight or curved cutting edge is used, the cutting part is sharpened for rough processing at an angle of 70 ... 75 °, and for finishing - 90 °. Internal cylindrical surfaces are treated with a trihedral scraper.

Calibration tools for scraping are plates, flat and angled rulers, rollers.

The process of preparation and scraping is carried out in the following sequence. The surfaces of the part are cleaned and wiped. A thin layer of paint (soot, azure, and others mixed with machine oil) is applied to the calibration plate and the part is carefully placed on the plate with the treated surface. Then the part is moved in a circular motion on the plate and carefully removed. On the treated surface, the most protruding places are slightly stained. In the process of scraping, the metal is gradually scraped off from the painted places, moving the scraper forward with a slight pressure, each time in different directions so that the strokes intersect at an angle of 90 °. With rough scraping, the working stroke of the tool is 10 ... 15 mm, and with finishing - 4 ... 5 mm.

To check the accuracy of scraping the planes, a frame of 25x25 mm in size is applied to them in several places and the number of spots in the area bounded by the frame is counted. Scraping is completed with the following number of spots: rough - 8 ... 10, semi-finish - 12, finish - 15, fine - 20, thin - 25. In addition, the surface should have a small and uniform stroke, without deep scraper marks. The accuracy of scraping curved surfaces is checked with a template - a grid.

Lapping and polishing– surface treatment operations with especially fine-grained abrasive materials using lapping.

These operations achieve not only the required shape, but also the highest accuracy (5 ... 6th grade), as well as the lowest surface roughness (up to 0.05 microns).

To prepare the grinding mixture, finely divided abrasive materials are used: electrocorundum, silicon carbide, boron carbide, synthetic diamonds, chromium oxide, etc. Machine oil, kerosene, stearin and petroleum jelly are used as a binding liquid.

When grinding, GOI pastes are widely used, containing in their composition, in addition to the abrasive and binder, surfactants, as well as diamond pastes.

The lapping material must be softer than the surface of the lapping material. It is usually made of gray cast iron, bronze, copper and wood. The shape and dimensions of the lap must be very precise, as they replicate the surface being machined.

For lapping planes, lapping plates are used, along which the parts are evenly moved in circular motions with slight pressure. By lapping on the plates, a high processing accuracy is obtained.

The inner conical surfaces are rubbed with conical lapping plugs, and the outer ones - in special lappings with a conical hole.

Lapping is carried out until the surface becomes matte or mirror. The quality is checked with paint, which should evenly lay down over the entire surface.

Fitting and assembly work- these are assembly and dismantling works performed during the assembly and repair of machines. Various connections of parts performed during the assembly of machines are divided into two main types: movable and fixed. When performing locksmith and assembly work, a variety of tools and devices are used: wrenches (simple, socket, sliding, etc.), screwdrivers, punches, pullers, devices for pressing and pressing out.

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INTRODUCTION

The name of the profession "locksmith" is of German origin. Locksmith (in German "Schlosser" from Schloss - lock) skilled workers in metal processing, assembly of machinery and equipment and other metal work, a profession widespread in all sectors of the national economy. Locksmiths are: toolmakers, pattern makers, assemblers, repairing machine tools, cars, oil and gas processing equipment, equipment, plumbers, etc. Locksmiths perform a variety of metalworking work, usually supplementing machining or completing the manufacture of metal products, assembling machines and mechanisms, as well as adjusting them. . Vices, clamps, clamps, pliers are used as fastening and clamping locksmith tools; riveting hammers, riveting machines, supports, roller rolling, soldering irons, blowtorches are used to assemble permanent joints; wrenches, screwdrivers, stud drivers, fittings are used to assemble threaded connections ; compasses, inside gauges, thickness gauges, measuring rulers, tape measures, probes, calipers, stihmas, micrometers, thread gauges, squares, goniometers, levels, straightedges, straightening plates, etc. With the development of technology and production technology, manual processing metal is gradually replaced by machine. At the beginning, the maintenance of the machine was carried out by people, and then it became automated. At the present stage, the operation of machines is controlled with the help of computers operating according to a predetermined program, capable of independently readjusting them when working conditions change. The profession of a locksmith has not lost its significance in a modern enterprise. Plumbers and electrical fitters work at the zero cycle of the construction of the enterprise, laying energy routes. The building of the enterprise is erected by metalwork fitters. After construction, the equipment supplied to the enterprise is installed by fitters, and then fitters. Each of these groups of locksmiths is characterized by knowledge and professional skills specific to their work. However, the main base for each locksmith is the possession of general locksmith operations.

1. FITCHWORK

1.1 Planar marking of metal

Planar marking is the drawing on the surface of the material being processed, lines indicating the boundaries to which the material must be processed, as well as lines defining the centers of future holes. Lines with punched grooves applied to the surface of the material are called marking risks. According to the marking risks, all subsequent processing of the material is carried out: cutting, filing, drilling, etc. Planar marking is one of the most critical operations, since the accuracy of further processing depends on the quality of its implementation. The accuracy of planar marking is low and ranges from 0.2 to 0.5 mm. Planar marking is widely used in individual and small-scale production. In serial and mass production, planar marking is mainly used in the manufacture of technological equipment (dies, templates, fixtures, etc.), as well as in the manufacture of various parts intended for equipment repair. Planar marking is a laborious operation. Therefore, where possible and rational, they try not to use planar markings. However, the processing of materials without marking requires the use of various devices (stops, templates, conductors, etc.). It is known that the cost of each fixture pays off only when manufacturing large quantities of parts of the same shape and size, this can only be done in conditions of serial and mass production. In individual and small-scale production, in the manufacture of single parts, it is more profitable to manufacture them using markings than to manufacture one or another device. When performing copper and tin works, many parts are manufactured without the use of planar markings. On sheet shears with inclined knives equipped with back and side stops, sheet material is cut without marking into parts of a rectangular, square, trapezoidal and oblique shape. Profiles are bent on edge bending machines without marking, i.e., along the stop on the machine. The use of conductors and templates allows you to drill holes in parts without first marking them. With planar marking, both the coppersmith and the tinsmith have to perform various geometric constructions: draw parallel and perpendicular lines, divide straight lines into equal parts, build angles, divide angles and circles into equal parts, draw line conjugations, etc. These geometric construction copper and tinsmith must be able to do quickly and accurately, for which you need to know the basics of technical drawing. The coppersmith and the tinsmith have to produce products of various shapes from sheet and profile material. For the manufacture of products, blanks of the appropriate shape and size are required. To find the actual dimensions of such workpieces, one must be able to calculate the surface area of \u200b\u200bthe products and draw their sweeps. These scans are obtained by planar marking. Planar marking is carried out depending on the production conditions by several methods: according to the drawing, template, sample and in place. When performing planar markings, safety regulations must be observed. In order not to cut your hands with the edges of the sheet material when laying it on the marking table, as well as when removing it from the table, after marking is completed, gloves are put on your hands. When using prisms and linings, measures are taken to prevent them from falling. It is recommended to put protective rubber caps on the tip of the ends of scribers and compasses that are temporarily not in use.

1.2 Straightening, metal bending

Metal dressing is an operation to remove defects on workpieces and parts in the form of convexity, concavity, warpage, waviness, curvature, etc. The meaning of metal straightening is to expand the concave part of the metal and compress the convex surface of the metal. The metal is straightened, both in a heated state and in a cold one. The choice of one or another type of dressing depends on the size of the cuts, the deflection and the material of the part.

Metalworking in this way can be either manual (on a cast-iron or steel plate) or machine (on presses or rollers). The correct plate should be massive. Its dimensions should be from 400X400 mm. or up to 1500X1500 mm. The slabs are mounted on wooden or metal supports, which provide good stability and a horizontal position. Straightening headstocks are used for straightening hardened parts (straightening). They are made of steel and hardened before use. The headstock working surface itself can have a spherical or cylindrical shape with a radius of 100-200 mm. (see photo) Manual dressing of metal is carried out with special hammers with a plug-in, radius, round soft metal head. Thin sheet metal is most often ruled with a mallet. When straightening metal, it is very important to choose the right place where to strike, and the impact force must be commensurate with the amount of curvature and change as you move to the best condition.

Types of metals that have a twisted bend are processed by untwisting. Round metals can be straightened on an anvil or plate. If the twist has several bends, then you need to start editing from the edges, and then process the bends in the middle. The most difficult in this form is the editing of sheet metal. This type of metal must be placed on the plate with a bend or bulge up. Blows should be applied towards the bulge (bend) from the edges of the sheet. Under the influence of blows, the convex part of the sheet will straighten out, and the flat part will stretch. During the straightening of hardened sheet metal, not strong, but frequent hammer blows are applied, directed from the concavity to the edges. The part is straightened, and the upper parts of the metal are stretched.

Large cross-section round and shaft workpieces are machined using a hydraulic or screw process. In terms of the nature and methods of work, straightening metals is very easy to compare with another type of metal processing - this is the process of bending metals. Metal bending is used to give the workpiece a shape according to the drawing. Its meaning is that one of the parts of the workpiece is bent to the other at a certain angle. The deformation of the part must be plastic, and the bending stress must have a lower characteristic compared to the elastic limit, because if you use further changes in the structure of the part, for example, how it will be difficult to cut metal. In this case, the workpiece will retain its shape after the end of the loading process. Manual bending is done in a vice, a metalwork hammer and other devices are used. The sequence of metal bending depends on the material and the contour of the workpiece. Sheet metal bending is done with a mallet. When using various mandrels for metals, the shape of the mandrels must correspond to the shape of the part, taking into account the deformation of the metal. When bending a workpiece, you must correctly set its dimensions. The length of the workpiece is determined according to the drawing, taking into account all the bends on the workpiece. For parts that bend without rounding from the inside and at a right angle, the allowance of the part for bending should be from 0.5 to 0.8 mm of metal thickness.

During the plastic deformation of the part during the bending process, the elasticity of the materials is necessarily taken into account: the bending angle slightly increases after the load is removed. After removing the load, the part can be processed in different ways, one of them is metal cutting. Manufacturing and metalworking of parts with very small bending radii can lead to rupture of the outer layer of the workpiece. The size of the minimum bending radius on the metal depends entirely on the properties of the metal, the quality of the workpieces and the technology of their bending. Parts with a small bending radius must be made from ductile materials.

Sometimes during the manufacture of products there is a need to obtain curved pipes bent at ordinary angles. Bending can be performed over welded and seamless pipes, as well as pipes made of alloys and non-ferrous metals. Pipe bending is carried out with filler (most often river sand), the process is possible without it. In this case, it depends on the diameter, its bending radius, and the material of the pipe. Filler, i.e. sand keeps the pipe walls from forming wrinkles and bending folds on them. By cutting metal pipes, they are given the desired shape and size.

1.3 Cutting metal

Cutting is a locksmith operation in which, with the help of a cutting tool (chisel), excess layers of metal are removed from the workpiece or part or the workpiece is cut into pieces.

With modern methods of processing material or workpieces, metal cutting is an auxiliary operation.

Metal cutting is carried out in a vice, on a slab and on an anvil using a bench hammer, a bench chisel, a cross-cut, a blacksmith's chisel and a sledgehammer.

Cutting metal can be horizontal and vertical, depending on the location of the chisel during the operation. Horizontal felling is carried out in a vice. In this case, the back face of the chisel is set to the plane of the vise jaws almost horizontally, at an angle of not more than 5°. Vertical felling is performed on a slab or anvil. The chisel is installed vertically, and the material to be cut is laid horizontally on the plate.

For metalwork cutting, hammers weighing 400, 500, 600 and 800 g are used. Hammers are mounted on handles made of hard and viscous wood (birch, maple, oak, mountain ash). Handles should be oval in shape, with a smooth and clean surface, free of knots and cracks. The length of the hammer handle weighing 400-600 g is 350 mm, weighing 800 g is 380-450 mm. To prevent the hammer from jumping off during operation, the end of the handle on which the hammer is mounted is wedged with wooden or metal wedges 1–3 mm thick. The wedges are placed along the major axis of the cross section of the handle. Wooden wedges are put on glue, and metal wedges are buffed so that they do not fall out.

The working part of the chisel and the crosscut is hardened to a length of at least 30 mm, and the head is hardened weaker than the blade (to a length of about 15-25 mm) so that it does not crumble or crack when struck with a hammer.

The rest of the chisel and cross cutter should remain soft. Chisels and crosscuts should not have cracks, captivity and other defects.

The most commonly used chisels are 175 and 200 mm long with blades

20 and 25 mm wide. For cutting grooves in steel and cast iron, crosscuts 150–175 mm long with a blade 5–10 mm wide are used. The heads of the chisel and crosshead are forged into a cone, which ensures the correct direction of the hammer blow and reduces the possibility of the formation of a mushroom cap on the head.

The angle of sharpening chisels and crosscuts depends on the hardness of the metal being processed. For cutting cast iron, hard steel and hard bronze, the sharpening angle of the tool is 70 °, for cutting medium and mild steel - 60 °, for cutting brass, copper and zinc -45 °, for cutting very soft metals (aluminum, lead) - - 35--45°.

Locksmith tools are sharpened on grinding machines with abrasive wheels. During sharpening, the working part of the tool (blade) is very hot and can be tempered. When tempering, the hardness of the hardening is lost and the tool becomes unusable for further work. To avoid this, the working part of the tool is cooled with water during sharpening. Figure 6 shows how to hold the chisel while sharpening and how to check that the corner is sharpened correctly.

The productivity and cleanliness of metal cutting depend on the correct working methods. When felling, you need to stand steadily and straight, half-turned to the vise. The hammer is supposed to be held by the handle at a distance of 15-20 mm from the end and strike hard at the center of the chisel head. You should look at the blade of the chisel, not at its head, otherwise the blade of the chisel will go wrong. The chisel is supposed to be kept at a distance of 20-25 mm from the head.

Billets from sheet or section steel can be chopped off in a vise at the level of the jaws or at risks above the level of the vise jaws.

When cutting at the level of the vise jaws, the workpiece is clamped firmly into the vise so that the upper edge protrudes 3–4 mm above the jaws and the first chip is cut down for the entire length of the workpiece. Then the workpiece is rearranged in a vise so that the upper edge protrudes 3-4 mm above the level of the vise jaws, and the second chip is cut down. So sequentially cut off the product to the required size.

When cutting above the level of the vise jaws, the workpiece is clamped in a vice so that the marked risk is above the level of the vise jaws and parallel to them. Cutting is carried out sequentially according to the marked risks, as well as when cutting according to the level of the vise jaws. When cutting, the chisel blade should be located at an angle of 45 ° to the metal being chopped off, and the head should be raised upwards at an angle of 25-40 °. With this arrangement of the chisel, the cutting line will be a ditch and the felling will be faster.

A large layer of metal on a wide plane of the workpiece is cut down as follows: the workpiece is clamped in a vice, a chamfer is cut off with a chisel, transverse grooves are cut with a crosscut, and then protruding edges are cut with a chisel. When cutting grooves with a cross cutter, the chip thickness should be no more than 1 mm, and when cutting off protruding edges with a chisel, from 1 to 2 mm.

Strip steel is cut on a plate or anvil (9). Previously, cut lines are applied to both sides of the strip with chalk. Then, laying the strip on the anvil, set the metalwork chisel vertically on the marked risk and with strong blows of the metalworker's hammer cut the strip to half its thickness. Then the strip is turned over, notched on the other side and the part to be cut off is broken off.

Round metal is cut in the same way, with the bar turning after each blow. Having cut the bar along the entire circumference to a sufficient depth, the part to be cut off is broken off.

Carbon and alloy structural steel up to 20–25 mm thick can be cold cut on a plate or anvil using blacksmith chisels and sledgehammers. To do this, on -t * "or, Four sides of the workpiece are applied with chalk overcut lines. Then the metal is laid on the anvil, the blacksmith's chisel is set vertically on the marking line, and with strong blows of the sledgehammer, the metal is cut along this entire line to the required depth, gradually rearranging the chisel. The metal is also cut on the other side or on all four sides, after which the cut off part is broken off. To speed up and simplify cutting, an auxiliary tool is used - nizhiik (cutting). The undercut with the shank is inserted into the square hole of the anvil, then the workpiece is placed on the undercut, and a blacksmith's chisel is placed on top, as shown in 10, D, and the chisel is struck with a sledgehammer. Thus, there is a simultaneous cutting of metal from both sides with a chisel and undercutting.

Cast iron pipes are cut with a chisel on wooden linings. First, a cut line is marked with chalk around the circumference of the pipe, and then, placing linings under the pipe, in two or three passes they cut the pipe with a chisel along the marking line (I, a), gradually turning it. After checking the depth of the cut groove, which should be at least 73 of the pipe wall thickness, a part of the pipe is separated with light hammer blows. When working, the chisel must be held perpendicular to the axis of the pipe. The end of the pipe at the place of the cut must be even, perpendicular to the axis of the pipe and coincide with the intended line of the cut. The correctness of the Butt is checked by eye, and controlled with a square.

More productive is the mechanized cutting of metal with a pneumatic hammer operating under the action of compressed air with a pressure of 5-6 kgf / cm2. Compressed air is supplied to the hammer through hoses from the compressor. The pneumatic hammer consists of a cylinder into which the chisel is inserted, a piston moving in the cylinder, and an air distribution device. Thanks to the air distribution device, the piston receives forward and return motion and quickly moves back and forth along the cylinder. In forward motion, the piston hits the chisel, which cuts the metal. The hammer is put into operation by pressing the trigger 6. The worker holds the hammer with both hands and directs the chisel to the cutting site.

A manual screw press is used for cutting cast-iron sewer pipes with a diameter of 50 and 100 mm. It consists of a welded frame 2, two side racks 5, having threaded necks in the upper part, on which a traverse 6 is put on. The traverse is attached to the racks with nuts. On the traverse with a nut and a screw. In the lower part of the racks there is a lower fixed clip with a plug-in lower knife, and in the upper part of the racks - an upper movable clip 3 with a plug-in upper knife. The upper movable cage is fastened to the lead screw with a plate 12 and bolts 4 and rises and falls together with them. Side racks 5 are guides for the upper cage. From below, a channel with uprights at the ends is welded to the bed plate. This channel is a guiding element when laying a pipe for cutting.

Knives are attached to clips with bolts. The inner diameters of the knife blades should be 2 mm less than the outer diameters of the pipes being cut. For each pipe diameter there is a pair of knives and a pair of rollers mounted on the channel for feeding pipes to the knives.

The press works in the following way. First, knives and rollers are installed in accordance with the diameter of the pipes to be cut. Having raised the upper clip with the knife with the flywheel, the pipe is laid on the rollers so that the cut line coincides with the tip of the lower knife. Then, with a sharp jerk, the flywheel is turned in the opposite direction, while lowering the lead screw with the upper knife. From the sharp pressure of the lower and upper knives, an incision first appears on the sides of the pipe, the pipe is wedged and then splits into two parts. The press is served by one worker.

The VMS-36A mechanism works on the principle of a drive press. A gearbox with two heads 2 is mounted on the welded frame of the mechanism. One head is designed for cutting pipes with a diameter of 50 mm, the second for pipes with a diameter of 100 mm. Pipes are cut by four movable knives mounted in the cartridges of the heads of the mechanism. The mechanism is powered by a 1.5 kW electric motor with a rotation speed of 1420 rpm. The engine is started with a foot pedal.

To cut pipes, first turn on the electric motor. Then they take a pre-marked pipe and lay it on supports so that the marking line on the pipe coincides with the knife blade. After that, the foot is pressed on the pedal. The knives are lowered onto the pipe, which is cut along the marking line by the pressure of the knives. After cutting, the knives return to their original position and the work of the head automatically stops. The time for cutting pipes of one cycle is 3 s. Each of the four knives covers the cut pipe for a length equal to a quarter of its circumference. 15 shows the planes of cutting knives, the geometry of which takes into account the characteristics of the material being cut, i.e., the brittleness of cast iron. To prevent destruction and ensure a smooth and even cut surface of the pipe being cut, the cutting edges of the knives are made discontinuous due to the cut transverse grooves. The radius of the circle formed by the cutting edges of the knives must be less than the outer radius of the pipe being cut. Blade sharpening angle 60°. The cutting process is as follows.

When approaching, the knives at the first moment touch the pipe at eight points. With further approach, they crash into the pipe; wells are formed, located around the circumference. Microcracks appear near the holes, directed from the hole to the hole and into the depth of the metal. During the process, the microcracks merge and the traveling cracks of the same direction are formed, which advance the feed of the knives. This causes one end of the pipe to separate from the other.

With knives of the described design, rings 20 mm long can be cut off from cast-iron sewer pipes.

When cutting, in order to avoid bruises and injuries, the following precautions must be observed: firmly put a hammer or sledgehammer on the handle; securely strengthen the metal in a vice and, when cutting on an anvil, support the cut off part of the workpiece; use fencing nets when cutting hard or brittle metal so that flying fragments do not injure a person working or nearby; work with serviceable tools and on serviceable machines;

when cutting pipes on a press, wear gloves. Before cutting pipes, it is necessary to check the serviceability of the mechanism, electrical equipment and protective fences.

1.4 Metal cutting

During locksmith and procurement work, metal is cut in cases where it is necessary to separate a part of a certain size or a given shape from a billet of sectional, shaped steel or pipes. This operation differs from felling in that it is performed not by shock, but by pressing forces, and the adjacent thorns of the main and separated parts of the metal have straight planes without bevels. Steel strip, round, angular or other is cut in a vice, and pipes are cut in a clamp using hand hacksaws.

Metal is cut with manual and mechanized hacksaws.

Hand saws are used sliding with a horizontal or inclined handle. Hacksaws with a horizontal handle consist of left 3 and right 5 frames, clip 4 and handle 7. The hacksaw blade is inserted into the slots of the head / tension screw and head 6 of the shank. They are tightly reinforced with pins and pulled with a lamb 2. The hacksaw can be moved apart to different lengths according to the length of the hacksaw blade.

For hand saws, hacksaw blades 300 mm long, 15 mm wide and 0.8 mm thick are used. The angle of sharpening of the tooth of the hacksaw blade is 60 °, both hacksaw blades are parted so that the blade does not get stuck in the slot of the metal. The lower part of the blades with teeth is hardened, and the upper part is left unhardened, which reduces the breakage of hacksaw blades during operation.

When cutting metals of unequal hardness, hacksaw blades with teeth of various sizes are used. For cutting soft metals, blades with 16 teeth per 25 mm blade length are used, for harder metals (ornamental or well-annealed tool steel) - with 19 teeth, for hard metals (cast iron, tool steel) - with 22 - teeth 25 mm long. For cutting thin strip and small angle steel, blades with 22 teeth per 22 mm blade length are used so that at least two or three teeth are accommodated along the thickness of the metal. With a larger tooth, the blades break.

The blades are inserted into the hacksaw with the teeth forward. The cutting blade must not be too tight, otherwise it will break during operation.

The hacksaw is held with two hands during operation: with the right hand, by the handle, and with the left, the second end of the hacksaw is supported and reciprocated. The position of the hacksaw during operation should be close to horizontal, so that the pressure of the worker on both ends of the hacksaw is more uniform.

When cutting, the metal is fixed in a vice, and the pipes are fixed in a clamp so that the cut line is located close to the vise jaws or to the clamp. With this fastening, the material does not vibrate during cutting, the hacksaw blade does not break, and the cut line is smooth. In the case of cutting a wide material, the hacksaw is held horizontally, and in the case of cutting pipes of strip or shaped steel, it is slightly inclined. The working stroke of the hacksaw is carried out forward with pressure, and the reverse (idle) stroke is without pressure. The pressing force depends on the hardness of the metal.

When cutting shaped and flat steel, do not press on the blade very hard to avoid jamming and breaking it. At the end of the cut, the free end of the material must be supported and the cut completed. Otherwise, material breakage, pinching and breakage of the web may occur. The end of the material will be uneven.

To increase labor productivity and properly organize the workplace, you should: prepare in advance the required number of hacksaw blades; pre-mark the entire batch of metal to be cut and lay it on a workbench on the left side of the vise; the material to be cut is placed in a certain place at the workbench in size.

When working with a hacksaw, it is necessary to follow the following safety rules: firmly fix the handle on the shank so that during operation it does not come off and the tip of the shank does not injure the hand; firmly strengthen the cut metal in a vice so that it does not fall out when cut with a hacksaw and does not hurt the worker's leg; sweep sawdust from the workbench with a brush.

A manual mechanized hacksaw is more productive than an ordinary one. An electric motor is mounted in the body 6 of the hacksaw, on the shaft of which a drum with a spiral groove is mounted. A pin enters the groove of the drum. When the motor shaft and the drum rotate, the slider and the hacksaw blade attached to it move. A bar is used to stop the hacksaw blade when cutting metal.

When cutting pipes manually, as mentioned above, they are fixed in clamps.

Clamps are two-column and single-column. Two-column clamps are more convenient, as they allow, by slightly raising the clamping prism, by turning the screw, remove the pin from the holes, fold the upper part of the clamp and easily remove the pipe from it to the side.

To clamp steel pipes and pipe blanks with a diameter of 15--50 mm, pneumatic clamps of various designs are used.

The pneumatic diaphragm clamp VMS-DP-1 consists of a body, sponges with guides, steel levers (two large and two small), a flat diaphragm, a rod and a return spring. One or two layers of sheet rubber are used as a diaphragm (depending on its thickness).

The pipes are clamped by supplying compressed air to the drive with a working pressure of 4 kgf / cm2. The pipe is released by means of a spring after the compressed air has been vented to the atmosphere.

The force of the return spring, i.e., the opening of the jaws, is regulated by a round nut screwed into the lower part of the pneumatic chamber housing.

Pneumatic clamps are used in pipe preparation shops of assembly plants when assembling assembly units.

Driven hacksaw 872A is designed for cutting various workpieces from high-quality and profile metal of round and square sections. The machine bed in the upper part forms a table on which a vice is installed to strengthen the cut material. The machine is equipped with two types of vise: with parallel jaws, in which rectangular material is strengthened, and jaws with V-shaped notches, in which round material is strengthened. Vices with parallel jaws rotate around the axis, which makes it possible to fix the cut material in them at different angles (up to 45 °) to the hacksaw blade.

At the top of the machine is a trunk that can be lowered and raised by means of a cylinder for lifting and lowering the frame. The saw frame 5 moves along the guides of the trunk with a hacksaw blade attached to it. The frame is driven in reciprocating motion by a crank mechanism consisting of a crank and a connecting rod. The hacksaw is driven by an electric motor 10 connected to the crank shaft by a gear train.

The blade, due to the mass of the frame, presses on the cut material. Cutting occurs only with a straight hacksaw blade. During the reverse stroke, the trunk with a hacksaw blade rises slightly under the action of an oil piston pump; due to this, the cutting teeth become less blunt.

Work on the machine as follows. First, a cut line is marked with chalk on the metal or pipe being cut, then they are strengthened in the vise of the machine so that the cut line coincides with the hacksaw blade. After that, turn on the machine and cut the metal.

To increase the productivity of the machine, sectional steel of small sizes and pipes of small diameters are placed in the vise of the machine in packages of 8-14 pieces, depending on their size and cross section, and each package is cut entirely. When cutting, the hacksaw blade is cooled by the emulsion supplied by the pump. The composition of the emulsion includes 10 l

water, 1 kg of liquid soap and 0.5 kg of drying oil. Before use, the mixture is thoroughly mixed and boiled. Disadvantages of a driven hacksaw: its low productivity and rapid wear of hacksaw blades.

When working on a drive machine, the following safety rules must be observed: work only on a serviceable machine; support the cut-off part of the material with special stands or hands so that it does not fall on your feet; monitor the serviceability of the electrical wiring, knife switch and electric motor to prevent electric shock.

Driven press scissors C-229A are designed for cutting high-quality, shaped and sheet steel up to 13 mm thick. In addition, they are used for punching round holes up to 20 mm in diameter with a material thickness of up to 15 mm and stamping small parts.

The frame 8 of the machine is mounted on a trolley 7, through which the shear press can be transported from place to place. The sheet steel cutting unit 6 consists of a lower fixed knife, an upper movable knife and a stop, with the help of which the cut material is pressed against the lower knife. The node 5 for cutting steels of different profiles consists of two vertical knives having holes that correspond to different steel profiles. The machine is powered by an electric motor 3 through a drive 4.

Sheet or strip steel is placed on the lower knife, pressed with an emphasis and, by turning on the mechanism of the lower knife, is cut. The design of the press scissors allows you to cut metal of any length. Hole punching and stamping is carried out on a hole-punching 2 and a die-cutting / device by pressing the machine switch-on lever.

The powered combi shear is portable, easy to handle and suitable for outdoor areas and harvesting shops.

When working on press shears, it is necessary to follow the following safety rules: start work only if there are protective covers on the moving parts, after checking the grounding of the electric motor housing; before starting work, lubricate the press scissors and check their operation at idle; work with the established stops for the material; when laying the material to be processed in the press-shears, keep your hands at a safe distance from the knives and the punch; remove small stamped parts only with pullers, hooks or tongs; do not lubricate gears and other moving parts when the motor is running and when cutting material.

The VMS-32 pipe cutting mechanism is designed for cutting steel water and gas pipes with a diameter of 15-50 mm. Diameter 160 mm. The gearbox is rotated by means of a tension screw and a handwheel. The frequency of rotation of the cutting disc is 193 rpm. The VMS-32 mechanism is driven by a 1.1 kW electric motor connected to the gearbox shaft by a flexible coupling. The cutting disc of the VMS-32 mechanism must have a regular cylindrical shape with a sharpening angle of about 60 °. As the blade becomes dull, it must be sharpened again. It is recommended to sharpen with a portable abrasive wheel on a flexible hose while rotating the abrasive wheel and cutting disc. The mechanism is supplied with supports that serve as supports when cutting long pipe blanks.

The marked pipe is placed on special rollers so that the cut line coincides with the cutting disc. Then the pipe is covered with an upper chute - a trough, locked with a pin and the mechanism is started. By turning the handwheel, the cutting disc is brought closer to the pipe. The pipe comes into rotation due to friction between it and the cutting disc. From the pressure transmitted to the rotating disk, it crashes into the metal and cuts the pipe. After cutting the pipe by turning the steering wheel, the gearbox with the roller is pulled up.

The VMS-35 pipe cutting mechanism is designed for cutting water and gas pipes with a diameter of 15--70 mm. The pipes are cut by a cutting disc with a diameter of 160 mm, mounted on the shaft of the oscillating gearbox. When cutting, the pipe rotates. The supply of the cutting disc to the pipe and its return to its original position are carried out using a pneumatic device.

1.5Filing metal

The sawn product, in order to give it a stable position, is firmly clamped in a vice.

A layer of rust and scale on the workpiece and the crust of the casting are filed with an old bastard file so as not to spoil a good one, which wears out quickly. Then they start roughing the part with a suitable bastard file and then finish it with a personal file. In order not to spoil the vise jaws during the final filing, they are put on overlays made of copper, brass, lead or aluminum.

The cleanliness and accuracy of filing depends on the installation of the vise, the position of the body of the worker at the vice, working methods and the position of the file.

When installing the vise, the top of their jaws should be at the level of the worker's elbow. The correct position of the worker at the vise is shown in Figure: 36. When filing, it is necessary to stand on the side of the vice - half-turned, at a distance of about 200 mm from the edge of the workbench. The body must be straight and rotated 45° to the longitudinal axis of the vise.

The legs are spaced to the width of the foot, the left leg is extended slightly forward in the direction of the file. The feet are placed approximately 60° apart. When working, the body is slightly tilted forward. This position of the body and legs provides the most comfortable and stable position for the worker, the movement of the hands becomes free.

During filing, the file is held with the right hand, resting the head of the handle in the palm of your hand. The thumb is placed on top of the handle, and the rest of the fingers support the handle from below. The left hand is placed on the end of the file near his nose and the file is pressed. When rough filing, the palm of the left hand is placed at a distance of about 30 mm from the end of the file, fingers half-bent so as not to injure them on the edges of the product during operation.

When finishing filing, the end of the file is held with the left hand between the thumb located on the top of the file and the rest of the fingers at the bottom of the file. The file is moved back and forth smoothly along its entire length.

The product is clamped in a vise so that the sawn surface protrudes 5-10 mm above the vise jaws. In order to avoid recesses and blockages along the edges, when moving the file forward, it is evenly pressed against the entire surface being processed. The file is pressed only when moving it forward. With the reverse movement of the file, the pressure is weakened. The speed of the file is 40--60 double strokes per minute.

To obtain a properly processed plane, the product is filed with cross strokes alternately from corner to corner. First, the surface is filed from right to left, and then from left to right. Thus, the surface is sawn off until the necessary layer of metal is removed.

After the final filing of the first wide plane of the tile, they begin filing the opposite surface. In this case, it is required to obtain parallel surfaces of a given thickness. The second wide surface is filed with cross strokes.

The accuracy of the surface treatment and the accuracy of the corners are checked with a ruler and square, and the dimensions are checked with a caliper, inside gauge, scale ruler or caliper.

When preparing pipelines and manufacturing parts for sanitary systems, the ends of pipes and the plane of parts are sawn off. Marriage during filing is the removal of an excess layer of metal and a decrease in the size of the product compared to the required ones, the unevenness of the sawn surface and the appearance of "blockages". In the process of filing, use control and measuring tools and systematically check the dimensions of the workpieces.

When filing, the following safety rules must be observed: the handle must be firmly attached to the file so that during operation it does not jump off and injure the hand with the shank; the vice must be in good condition, the product must be firmly fixed in them; the workbench should be firmly strengthened so that it does not swing; when filing parts with sharp edges, do not press your fingers under the file during its reverse stroke; shavings are allowed to be removed only with a sweeping brush; after work, the files must be cleaned of dirt and chips with a metal brush; it is not recommended to put files one on top of the other, as this spoils the notch.

For the mechanization of filing operations, manual electric and pneumatic tools are used, as well as filing machines with a pneumatic drive and a flexible shaft. A special device is put on the end of the flexible shaft, which converts rotational motion into reciprocating motion. A file is inserted into this device, with which parts are filed.

The pneumatic file consists of a head tool for fixing it, a reducer movement converter and an electric motor. File stroke length 12 mm, number of double strokes per minute 1500.

1.6 Drilling, countersinking of metal

Holes are drilled according to preliminary marking made with a marking tool, or according to a template. The use of a template saves time, since the contours of the holes previously marked on the template are transferred to the workpiece. Holes of large diameters are drilled in two steps - first with a drill of a smaller diameter, and then with a drill of the required diameter.

Hole drilling can be through s m (the drill exits through the drilled hole); deaf (the depth of the hole is less than the thickness of the metal); for threading and reaming. The method of performing these types of drilling is the same, except for blind drilling, in which it is necessary to maintain the required hole depth. To do this, use devices that limit the feed of the drill to the desired depth. If there are no such devices, the machine is stopped after a certain time, the drill is removed and the depth of the hole is measured.

For accurate and fast drilling, the drill must be firmly and correctly fixed in the machine spindle or in the chuck so that it rotates without runout. If the drill beats, the hole will be irregular in shape, and the drill may break.

The pressure on the drill must be uniform and correspond to the hardness of the metal and the diameter of the hole. With soft metal and a small hole diameter, the speed and feed are increased. At the moment the drill exits the hole, the pressure should be loosened to avoid breakage of the drill. Since the drill heats up during drilling, it should be cooled by interrupting work. When working on machine tools, the drill is cooled with a soapy emulsion. When processing cast iron and bronze, the drill is not cooled. When drilling deep holes, periodically remove the drill from the hole and free the hole and grooves in the drill from chips.

42 shows a jig for drilling holes in flanges for steel pipes. Two support strips are welded to the lower part of the conductor with holes for fastening the conductor to the table of the drilling machine. The support strips are welded to the support disk with a hole in the middle, in which the flange foot rotates freely. The foot has a central threaded hole for the clamping bolt. A marking disk 3 is attached to the heel, on the circumference of which eight recesses are located at the same distance from one another (corresponding to the largest number of holes in the flange).

To drill holes, the flange is placed on a marking disk, strengthened by turning the handle 5 and centered using a cone 6.

The jig is mounted on a drilling machine so that the center of the drill coincides with the circle on which the holes in the flange are located. The flange is laid on the lining. Then the disk is installed so that the latch 7 falls into the recess on the circumference. After drilling the first hole, the disk is rearranged so that the latch falls into the recess for drilling the next hole.

Incorrect or loose clamping of parts, incorrect sharpening of drills, clogging of the drill groove with chips, insufficient cooling of the drill, incorrect cutting speed and feed of the drill break drills. With the wrong selection of drills, their improper fastening and incorrect methods of work, the following types of marriage are possible: the size of the hole is larger than required, an oblique hole, the hole is offset from the intended center, the depth of the hole is greater than required.

When drilling on machines, the following safety rules are followed: machines must have guards for rotating parts; workpieces should be firmly fixed on the table, and not held by hand during processing; hand-. tie your robe tightly; do not take on the rotating cutting tool and spindle; do not remove broken cutting tools from the hole with your hands, use special tools for this; do not lean on the machine during operation.

Deployment. To obtain holes with a clean surface or to fine-tune a hole for a ground part, an operation called reaming is performed. Reaming is performed manually or on a drilling machine using reamers. Manual reamers are driven by a hand crank.

Conical reamers are designed for reaming tapered holes.

For a cleaner surface treatment of holes and cooling of the tool during reaming, drilled holes in steel are lubricated with mineral oil, in copper with an emulsion, in aluminum with turpentine, and in brass and bronze, holes are reamed without lubrication.

Ream holes manually as follows. The part is firmly fixed in a vise. In the hole, the parts insert a reamer so that the axis of the reamer coincides with the axis of the hole. Then they begin to rotate the crank with a sweep to the right, smoothly feeding it forward. The reamer is rotated in one direction only.

Countersinking and countersinking. Countersinking is the processing of a hole obtained by casting, forging or stamping, to give it a cylindrical shape, the required size and a clean surface. Countersinking is an intermediate operation in the processing of a hole for reaming. Countersinking is done with a countersink. Countersinks are also used for processing conical and cylindrical recesses with a flat bottom.

A countersink has more cutting edges (three or four) than a twist drill and provides a cleaner hole.

Allowance for countersinking for holes with a diameter of 15 to 35 mm is given 1-1.5 mm.

The reaming operation is performed in the same way as deployment.

Countersinking operations are performed on a drilling machine, as well as drilling holes to the required depth.

2. THREADING

locksmith marking cutting reaming

Threading is the processing of a rod or hole in a part using a threading tool to obtain an external or internal screw thread, consisting of alternating spiral grooves and protrusions-coils. Cutting is performed on pipes, bolts, nuts, which are used for detachable connection of pipelines and various parts of equipment.

The main elements of the thread: profile, pitch, profile angle, depth, outer, inner and average diameters.

The cross-sectional shape of the thread is called the thread profile. According to the thread profile, there are triangular, rectangular, trapezoidal, etc. When assembling sanitary systems and parts, only triangular threads are used.

In the direction of the thread, the threads are divided into right and left.

By appointment, the threads are divided into fastening and special. Fastening threads include triangular threads, special ones - rectangular, etc. A triangular thread is called a fastening thread because it is cut on fasteners: bolts, nuts, screws. Thread pitch 7 is the distance between the tops or bases of two adjacent turns.

The angle of the thread profile is the angle formed by the intersection of the side faces (sides) of the thread.

The depth of a thread is the distance from the top to the bottom of the thread. Outer diameter - the distance between the tops of two opposite sides of the thread. The inside diameter is the distance between the bases of two opposite sides of a thread. Average diameter - the distance between the top of the thread and the base of the thread of the opposite side.

The relationship between the thread pitch, the thread depth and the number of turns per unit thread length is as follows: the larger the thread pitch, the greater the thread depth and the smaller the number of threads (turns) per unit thread length, and vice versa.

Triangular thread according to the system of measures is divided into metric and inch. A thread that has the form of an equilateral triangle in the profile with an angle at the vertex equal to 60 ° is called metric. It is used in instrumentation and mechanical engineering. The outer diameter of a screw or the inner diameter of a hole with a metric thread is measured in millimeters, and the thread pitch is iv millimeters and fractions of a millimeter. An inch thread has the same profile as a metric thread, but the angle at the top is 55 °. It differs from metric threads in a large pitch; measured in inches.

When assembling sanitary fittings, inch threads are used. Inch thread is fastening and pipe. The fastening thread differs from the pipe thread in that it has a larger pitch, gives a strong connection; used for cutting bolts, nuts, rods and holes. Pipe threads are used to connect pipes. It is smaller than the fixing one, since its depth is limited by the thickness of the pipe walls. Due to the greater number of threads per inch of thread length, the density of the pipe thread is much greater than the fastener thread.

External thread cutting. External threads on bolts, screws and rods are manually cut into dies.

Depending on the device, the dies are prismatic, sliding, round solid.

Prismatic dies consist of two identical halves, fixed in a die, which has the shape of a frame with handles. On the two outer sides of these dies, there are prismatic grooves, into which the prismatic projections of the klupp enter.

Sliding dies are installed in the die in such a way that the numbers and on the halves of the dies are opposite the corresponding numbers indicated on the frame. Otherwise, the thread will be incorrect. Fix the dies with a stop screw. A steel cracker plate is placed between the thrust screw and the die so that the die does not burst when pressed with the screw. The round die is fixed in the knob - lerkoderzhatel with two or four thrust screws.

To obtain the correct thread, it is necessary that the diameters of the rods and the holes to be drilled correspond to the size of the thread.

Sliding dies can cut a full thread with small deviations in the diameter of the rod. When threading with round solid dies, deviations in the diameter of the threaded rod are not allowed. With a larger diameter of the rod, the thread will turn out to be even, with a smaller one - incomplete.

Bolts when cutting threads are strengthened vertically in a vise.

Sliding dies are threaded in two or three passes, and round ones in one pass.

Klupp is rotated from left to right when cutting a right-hand thread and from right to left when cutting a left-hand thread. For 25-38 mm of working revolutions, 32-38 mm of revolutions are made back, so that chips break more easily. When rotating, press on the plate. At the end of threading, check its correctness by screwing on the nut.

To cool dies and taps when cutting threads in steel parts, drying oil or sulfofresol is used, and when cutting threads in cast-iron parts, turpentine is used. The use of mineral oil is not recommended, as it impairs the quality of the cut.

Cutting internal thread. The internal thread is manually cut with taps that are inserted into the knob. The tap has a chamfer (the end of the tap), which serves to cut the thread; calibrating (middle) - for guiding when cutting and calibrating a cut hole - and tail with a square head - it holds the tap in the wrench during operation.

CONCLUSION

In the course of this educational practical work, I learned how to use measuring tools; learned how to correctly mark up parts; to properly cut metal; metal cutting; to make straightening and bending of metal; manual filing of metal; drilling, countersinking, reaming.

LIST OF USED LITERATURE

1. A. I. Aristov, etc. Metrology, standardization, certification. - M.: INFRA-M, 2012, 256s. +CD-R.

2. Kholodkova A.G. General technology of mechanical engineering. - M.: Publishing Center "Academy", 2005.-224 p.

3. Cherepakhin A.A. Technology of processing materials - M.: Publishing Center "Academy", 2004.-272 p.

additional literature

1. Klepikov V.V., Bodrov A.N. Engineering technology. - M.: FORUM: INFRA-M, 2004.-860 p.

2. Muradyan S.V. Organization and technology of the industry. - Rostov n / a: "Phoenix", 2001.-448 p.

3. Ovchinnikov V.V. Fundamentals of the theory of welding and cutting of metals. - M.: KNORUS, 2012, 248 p.

4. Saltykov V.A. and other Machines and equipment of machine-building enterprises. St. Petersburg: BHV-Peterburg, 2012, 288 p.

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1.Technological repair process

The technological process of repairing a machine consists of a series of sequential operations that differ from one another in the nature of the work performed and the equipment used. However, many repair operations are similar to each other. For the production of the same type of technological operations at repair enterprises, special jobs are organized. They are equipped with machine tools, stands, fixtures, instruments and other equipment for disassembling, restoring parts and assembling machines and their components.

The main element of the technological process is an operation performed at one workplace and covering all the actions of the working (or working) and used equipment on one or more jointly processed, disassembled or assembled products. In addition to technological, in the repair industry there are also auxiliary operations: transport, washing, quality control, marking, etc. Technological operations are divided into transitions, passages and receptions.

The transition is a part of the operation, characterized by the invariance of the machined surface (or mating surfaces during assembly), the tool used and the operating modes of the equipment.

Pass - part of the transition, in which one layer of material is removed.

Reception is a complete set of individual movements of a person working in the process of performing an operation (for example, when drilling a hole in a product, the methods will be: fixing the product on the machine table, turning on cr.li ;, approaching the drill to the product, turning on the feed, turning off the feed, retracting the spindle, turning off machine, release of the product). The quality of repair operations is directly related to the qualifications of workers and the equipment of repair enterprises with equipment, fixtures and tools. A novice repairman must first of all study the tool that he will have to use and master the techniques for performing general locksmith operations.

1.1. Basic plumbing operations

The main general plumbing operations include: marking, cutting and cutting, straightening and bending, filing, drilling and reaming holes. Some of them, for example, marking products and drilling holes, the locksmith performs at specially equipped general workplaces for this purpose, and the rest at his individual workplace, where he also cuts threads, scrapes, and solders.

The rational organization of the locksmith's workplace allows to ensure the highest productivity, good quality and safe working conditions with the least expenditure of effort, time and money. It is important to properly equip the workplace and observe the established order on it once and for all.

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Basic plumbing operations - Other

Basic plumbing operations

EAT. Muravyov, Plumbing, Moscow, "Prosveshchenie" 1990, pp. 43-94

Basic plumbing operations

marking, cutting, straightening and bending of metals, cutting of metals, filing, drilling, countersinking, countersinking and reaming of holes, threading, riveting, lapping and finishing, soldering

Workplace - locksmith workbench

It is customary to call a workplace a certain section of the workshop, designed to perform certain work.

Rybins - removable wooden gratings installed on top of the deck.

A clamp is also called a screw clamp.

Chair vise.

Advantages - simplicity of a design and high durability. The disadvantage is that the working surfaces of the jaws are not parallel in all positions.

Rotary parallel vise.

The advantage is the possibility of a tighter clamping of the workpiece. In addition, you can fix at a certain angle.

A hand vise is used to secure small parts or workpieces that are inconvenient or dangerous to hold with your hands.

Marking tool

The operation of drawing small dots-depressions on the surface of a part is called. The point, axis of symmetry or plane from which all dimensions on the part are measured is called the marking base.

markup

The operation of drawing lines and dots on a workpiece intended for processing is called marking. The marking consists in drawing lines (rises) on the surface of the workpiece, which, according to the drawing, determine the contours of the part or the places to be processed.

Scribers are used to draw lines (marks) on the marked surface of the workpiece.

A center punch is used to apply recesses (cores) on pre-marked lines.

Marking (locksmith's) compasses are used for marking circles and arcs, dividing circles and segments into parts, and other geometric constructions when marking a workpiece.

Calipers

Caliper - a measuring (measuring) tool used in plumbing to remove and transfer the dimensions of a part to a scale

Goniometers

Used to measure angular values

Measuring tool

The measuring ruler is used for rough measurements

Straightening and bending

Editing - the operation of returning curved or bent metal products to their original straight or other shape. Giving the metal a certain configuration without changing its cross section and processing the metal by cutting is called flexible Bending of thin sheet metal is done with a mallet. For parts that are bent at right angles without rounding on the inside, the bending allowance of the workpiece should be 0.6 ... 0.8 of the metal thickness.

metal cutting

A percussion instrument consisting of a metal head, a handle and a wedge is called a hammer.

metal cutting

With the help of cutting, metal irregularities are removed (cut down) from the workpiece, hard crust, scale, sharp edges of the part are removed, grooves and grooves are cut, and sheet metal is cut into pieces.

For cutting profile (cutting) grooves (semicircular, dihedral, etc.), special crosscuts are used - groovers, which differ from each other in the shape of the cutting edge.

metal cutting

Hand shears - the simplest tool for cutting metal

Punches (notches)

Locksmith's tool, which is used for punching holes in sheet or strip metal or non-metal materials with a thickness of not more than 4 mm

Pipe cutters

Cutting steel pipes of relatively large diameters is a laborious operation, therefore special pipe cutters are used to perform it.

filing metal

Sawing - the process of removing the allowance with files, needle files and rasps

sharpening machine

Drilling, countersinking, countersinking and reaming

Drilling consists in obtaining and processing holes by cutting with the help of a special tool - a drill.

3e, the upper surfaces of the hole are machined in order to obtain chamfers or cylindrical recesses, for example, under a countersunk head of a screw or rivet.

Countersinking processes holes obtained by casting, stamping or drilling to give them a strict cylindrical shape, improve accuracy and surface quality.

scraping

The process of obtaining the accuracy of shapes, sizes and relative position of surfaces required by the working conditions to ensure their tight fit or tightness of the connection

Lapping

The removal of the thinnest layers of metal by means of fine-grained abrasive powders in a lubricating medium or diamond pastes applied to the surface of the tool is called.

To make accurate measurements, calipers are used. The caliper tools include a caliper, a caliper gauge, a caliper depth gauge, a caliper gauge.

There are three types of calipers: SC-I, SC-II, SC-III. The divisions marked on the bottom of the caliper slider are called vernier.

Linear measurements

Micrometers

Micrometer

A universal tool (device) designed for measuring linear dimensions by the absolute or relative contact method in the area of small sizes with a low error (from 2 microns to 50 microns, depending on the measured ranges and accuracy class), the converting mechanism of which is a screw-nut micropair.

Micrometer scale

Micrometer instruments allow measurements with an error of up to

0.01 mm (6.035)

Diametric expansion of the ends of the pipes to the outside in order to obtain a tight and strong press connection of the ends of the pipes with holes.

Soldering - the process of creating a permanent connection of metals using a filler binder

Tinning - coating the surface of metal products with a thin layer of tin or a tin-based alloy

Threading

Thread types

Metric thread - with a pitch and basic thread parameters in millimeters and a profile angle at the top of 60 °.

Inch thread - with basic thread parameters in inches, pitch in the number of threads per inch and a profile angle at the top of 55 °.

Pipe thread - with the main thread parameters in inches, a pitch in the number of threads per inch and a profile angle at the top of 55 °, designed to connect pipes, fittings and structural elements with pipe threads.

Dial indicator

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Basic plumbing operations.

Locksmith profession.

Under locksmith work, it is customary to understand work performed by hand and mechanized tools and completing the manufacture of most products through fitting and finishing work, connecting various parts into assembly units, kits and complexes and adjusting them.

Assembly fitters assemble various machines and mechanisms. Their maintenance and repair during operation is performed by repairmen. Locksmiths - toolmakers provide production with the necessary tools, facilitate and improve machining. Locksmiths for the installation of equipment, instruments, communications securely install them and the proper place, supply various types of energy and the main and auxiliary materials necessary for production. All these workers are united by the ability to perform various plumbing operations. This is what they learn in the general locksmith course.

The degree and type of professional training, the availability of knowledge, skills and abilities and the suitability to perform work of a certain content and complexity determine the qualifications of the worker. It is estimated by the tariff category, which is assigned to the worker by the qualification commission. The basis for this is the qualification characteristic given in special, tariff-qualification reference books. It states that the worker ʼʼshould be ableʼʼ and what ʼʼshould knowʼʼ in order to receive the appropriate wage category in his specialty.

Basic plumbing operations.

Consider the basic plumbing operations using the example of processing simple parts - a guide key (Fig. 1). Like wine from the drawing, the entire surface of the key is processed, it has three holes: two stepped mounting screws and one with a thread.

The key is made of keyed steel - a bar of rectangular section. To obtain a workpiece of the desired length, markings are made - lines are applied to the surface of the circle with a scriber, which determine the shape and dimensions of the part. Next, a chisel (the operation is commonly called cutting) or a hacksaw (cutting) separates the workpiece. During the cutting process, the workpiece must be bent. She needs to be corrected. Often it is required to perform the opposite work: to bend a workpiece that has a complex shape. Then perform bending.

It is impossible to obtain the correct shape of the surfaces of the part and the specified dimensions with the listed operations. Οʜᴎ are preliminary, procurement. Their goal is to prepare the workpiece for further processing, to ensure and accelerate it by removing large layers of metal. To give the key the desired shape and size, the workpiece is cast. A hole ø 11 mm and for M10 thread is obtained by drilling, and a local expansion of the hole size up to ø 17 mm is drilled. The thread in the drilled hole is cut with a tap. When the hole must have exact dimensions, it is deployed. Besides

considered, there are other operations: sawing and fitting - obtaining holes of complex shape and very precise processing of two parts to be joined; scraping and lapping - precise final operations that ensure high accuracy, tightness of joints; riveting, soldering and gluing are operations that allow parts to be joined together to form permanent joints.

As can be seen from the foregoing, all operations for the manufacture of any product must be performed in a certain

sequences. Together they make up the technological process of processing the part.

referatwork.ru

Basic plumbing operations.

Locksmith department.

date	clock	The content of the classes.	Material support.
		Theoretical part: General information: the importance of metalwork and metalwork and assembly work in the national economy. The concept of surface roughness and surface treatment. Sketches of products and blanks. Organization of the locksmith's workplace - typical equipment, working and measuring tools. Locksmith operations: marking, bending, cutting, cutting material. Practical part: Safety briefing. Preparation and equipment of the locksmith's workplace for this cycle of operations. Requirements for the working tool. The study of the elements of working drawings of products and blanks. Preparation of blanks for marking, straightening, straightening, bending, cutting, cutting blanks. Making hooks for hangers.	Locksmith's workplace. Journal of safety briefing. Files, calipers.
		Making a chisel.	Files, calipers.

Report in practice.

Locksmith's workplace equipment.

In metalwork workshops and on sites the equipment of individual and general use is located. Equipment for individual use are workbenches with vise. General use equipment includes: drilling and grinding machines, marking and checking plates, dressing plate, screw press, lever shears.

A vice is used to install and secure workpieces in a position convenient for processing.

The locksmith's working tool is divided into:

· Manual.

· Mechanized.

A typical set of hand tools for metalwork is divided into four groups:

1) cutting tool - files, hacksaws, chisels, drills, taps, dies, scrapers, reamers, abrasive tools;

2) auxiliary tool - hammers, cores, barbs, scribers, compasses, knobs, die holders;

3) fitting and assembly tools - wrenches, screwdrivers, pliers, hand vise, clamps, pullers;

4) measuring and control tools - rulers, calipers, calipers, calipers, micrometers, squares, goniometers.

Basic plumbing operations.

There are the following main plumbing operations:

Marking - drawing on the workpiece to be processed or the surface of the material, intended for the day the workpiece was received, marking lines.

Editing - irregularities, curvature, curvature, defects in the shape of blanks are eliminated.

Straightening - elimination of irregularities in the sheet or warping of the workpiece that has undergone hardening.

Bending - a workpiece or part of it is given a curved shape.

Cutting - removing an excess layer of metal or cutting a workpiece into pieces using a cutting tool.

Cutting.

Sawing - processing holes, grooves and grooves.

Fitting is the processing of one part according to the existing one in order to connect them.

Fitting - the exact mutual fit of parts.

Lapping - finishing of parts working in pairs to ensure the best contact of working surfaces,

Riveting - a type of assembly for the formation of an integral connection of two or more parts using rivets.

Soldering - a type of metalwork for the formation of a permanent connection using a molten intermediate material or alloy, called solder.

Tinning - coating the surface of metal parts with a thin layer of molten tin.

Thread cutting.

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Topic 1.1. The main operations of locksmith processing and their characteristics.

⇐ PreviousPage 3 of 6Next ⇒

Correlate the image with the type of processing and tool

Write your answer in the following form: 1-3-5

Topic 1.5. Tolerances and fits and technical measurements

Task 1 Name the main parts of the caliper

Fill the table

Task 2 Name the main parts of a micrometer

Fill the table

Task 3 Read the readings of the micrometer.

Task 4 Consider the schemes of tolerance fields. Determine the shaft tolerance, holes, type of fit.

	Tolerance field scheme		Hole tolerance		Shaft tolerance		fit type
1		1	0,052	1	0,040	1	with gap
2		2	0,046	2	0,019	2
3		3	0,030	3	0,032	3	Transitional
4		4	0,040	4	0,025	4	with interference

Topic 1.2. The main operations of locksmith processing and their characteristics.

Plumbing Test

Choose the correct answer

What is markup:

1. The operation of drawing lines and dots on the workpiece intended for processing

2. Operation to remove a layer of metal from the workpiece

3. The operation of applying a protective layer to the part. The operation of removing burrs from the part.

Choose the correct answer

Name the types of markup:

1. There are two types: straight and angled

2. There are two types: planar and spatial

3. There is one type: basic

4. There are three types: circular, square and parallel

Choose the correct answer

Name the tool used for marking:

1.File, needle file, rasp

2.Drill, countersink, countersink, countersink

3.Pipe cutter, hacksaw, scissors

4. Scriber, hammer, rectangle, center punch, marking compasses

Choose the correct answer

Name the measuring instruments used for marking:

1.Scale ruler, caliper, square, height gauge

2. Micrometer, indicator, thread template, probe

3. Scriber, hammer, rectangle, center punch, marking compasses

4. Mallet, trowel, sledgehammer, hammer with a round head

Choose the correct answer

On the basis of which the markup of the part is made:

1. Produced based on personal experience

2. Produce based on drawing

3. Produced based on the advice of a colleague

4. Produced on the basis of a defective part

Choose the correct answer

What is pinching:

1. This is an operation for applying points-recesses on the surface of the part

2.This is an operation to remove burrs from the surface of the part

3.This is a square hole sawing operation

4. This is an operation to straighten warped metal

Choose the correct answer

Tool used for cutting metal:

1.Applicable: tap, die, klupp

2.Applicable: center punch, scraper, countersink, mallet, trowel

3.Applicable: hacksaw, pipe cutter, metal shears

4.Applicable: metalwork chisel, chisel, groover, hammer

Choose the correct answer

What is metal straightening:

1. Operation to straighten bent or warped metal, only ductile materials are exposed

2. Operation to form a cylindrical hole in a solid material

3. Operation to form a threaded surface on the rod

4. Operation to remove a layer of metal from the workpiece in order to give the desired shape and size

Choose the correct answer

Name the methods of metal straightening:

1. Editing by twisting, breaking and extruding

2. Straightening by pressing, bending and crimping

3. Straightening by tightening, twisting and flaring

4.Editing by bending, pulling and smoothing

Choose the correct answer

Name the tools and fixtures used in editing:

1.Applicable: Parallel Vice, Chair Vice, Clamps

2.Applicable: stretching, crimping, support, chasing

3.Applicable: straightening plate, headstock, mallet, hammer, trowel.

4. Applicable: center punch, scraper, countersink, mallet, trowel

Choose the correct answer

What is metal cutting:

1. This is an operation related to the separation of materials into parts using a cutting tool

2. This is an operation, drawing marking lines on the surface of the workpiece

3. This is an operation to form a threaded surface inside the hole

4. This is an operation to form a thread on the surface of a metal rod

Choose the correct answer

Name a hand tool for metal cutting:

1. Chisel, cutter, groover

2.Hacksaw, hand shears, pipe cutter

3. Smoother, mallet, sledgehammer,

4. Reamer, countersink, countersink

Choose the correct answer

What is filing:

1. Operation to remove the broken saw from the cut on the surface of the workpiece

2. The operation of sawing the workpiece or part into pieces

3. Operation to remove a layer of metal from the surface of the workpiece using a cutting tool - a file

4. Operation to remove metal filings from the surface of the workpiece or part

Choose the correct answer

What tools are used for sawing?

1.Applicable: pliers, round nose pliers, wire cutters

2.Applicable to: round-faced hammer, square-headed hammer

3.Applicable: flat scraper, chisel, mallet

4.Applicable: files, needle files, rasps

Choose the correct answer

What are the types of file notches:

1. Triangular, pitted, square, oval

2.Linear, parallel, perpendicular, angular

3.Broach, shock, planed, persistent

4. Single, double cross, arc, rasp

Choose the correct answer

How many classes are files divided into depending on the number of notches per 10 mm of length:

1. Divided into 7 classes

2. Divided into 6 classes

3. Divided into 5 classes

4. Divided into 8 classes

Choose the correct answer

Name the cross-sectional shapes of the file:

1. Flat, square, trihedral, round, semicircular, rhombic, hacksaw

2. Oval, triangular, square, fork, straight, hexagon

3. Double-sided, three-sided, universal, specialized

4. Ordinary, professional, semi-professional

Choose the correct answer

What is drilling:

1. This is an operation for the formation of through or blind square holes in a solid material, using a cutting tool - a drill

2. This is an operation to form through or blind oval holes in a solid material, using a cutting tool - a drill

3. This is an operation to form through or blind triangular holes in a solid material, using a cutting tool - a drill

4. This is an operation for the formation of through or blind cylindrical holes in a solid material, using a cutting tool - a drill

Choose the correct answer

Name the types of drills:

1. Triangular, square, straight, angled

2. Hacksaw, manual, machine, machine-hand

3. Spiral, feather, centering, ring, rifle

4. Self-sharpening, basic, trapezoidal, thrust

Choose the correct answer

Name the types of shanks for a twist drill:

1. Oval and parallel

2. Cylindrical and conical

3. Semi-circular and outer

4. Special and regular

Choose the correct answer

What is a drill:

1. A cutting tool that cuts the workpiece into pieces

2. Cutting tool that forms cylindrical holes

3. Cutting tool used in soldering

4. Cutting tool for threading

Choose the correct answer

Name a manual drilling tool:

1. Drill, reamer, countersink, countersink

2. Bench drill, vertical drill, radial drill

3. Hand drill, brace, ratchet, electric and pneumatic drills

4. Lapping, scraper, frame, holder

Choose the correct answer

What is called stationary drilling equipment:

1. Such equipment is called equipment that is transferred from one workpiece or part to another.

2. Such equipment is called - equipment operating on electric current

3. Such equipment is called - equipment located in one place, while the workpiece being processed is delivered to it

4. Such equipment is called - equipment operating on compressed air

Choose the correct answer

Name the types of drilling machines:

1. Suspended, floor and diagonal

2. Desktop, vertical and radial

3. Screw-cutting, boring and slotting

4. Manual, machine and machine

Choose the correct answer

What is reaming:

1. This is an operation related to the processing of a previously drilled, stamped, cast and other hole in order to give it a more regular square shape, higher accuracy

2. This is an operation related to the processing of a previously drilled, stamped, cast and other hole in order to give it a more regular triangular shape, higher accuracy and higher roughness.

3. This is an operation related to the processing of a previously drilled, stamped, cast and other hole in order to give it a more regular oval shape, lower accuracy and lower roughness

4. This is an operation associated with the processing of a previously drilled, stamped, cast and other hole in order to give it a more regular geometric shape, higher accuracy and lower roughness

Choose the correct answer

Name the types of countersinks:

1. Pointed and blunt-nosed

2. Machine and manual

3. Stone and concrete

4. Solid and mounted

Choose the correct answer

What is deployed:

1. This is a threaded hole processing operation

2. It is an early-drilled hole processing operation with a high degree of accuracy.

3. It is a square hole machining operation with a high degree of precision

4. It is a taper hole machining operation with a high degree of precision

Choose the correct answer

Name the types of sweeps according to the method of use:

1. Main and auxiliary

2. Manual and machine

3. Machine and locksmith

4. Straight and tapered

Choose the correct answer

Name the types of sweeps according to the shape of the working part:

2. Rhombic and semicircular

3. Tetrahedral and trihedral

4. Straight and tapered

Choose the correct answer

Name the types of reamers according to processing accuracy:

1. Cylindrical and conical

2. Rough and finish

3. High-quality and low-quality

4. Manual and machine

Choose the correct answer

Name the thread profiles:

1. Triangular, rectangular, trapezoidal, thrust, round

2. Oval, parabolic, three-dimensional, overlap, scalloped

3. Semi-circular, mortise, heavy duty, anti-friction

4. Modular, segmented, tubular, countersunk

Choose the correct answer

Name the thread systems:

1. Centimeter, foot, battery

2. Gas, decimeter, calibrated

3. Metric, inch, pipe

4. Millimeter, water, gas

Choose the correct answer

Name the thread elements:

1. Tooth profile, outside corner, middle corner, inside corner

2. Profile angle, thread pitch, outer diameter, diameter, inner diameter

3. Tooth, modulus, outer radius, middle radius, inner radius

4. Tooth pitch, module angle, outer profile, middle profile, inner profile

Choose the correct answer

Name the tool for cutting internal threads:

1. Kreuzmeysel

Choose the correct answer

Name the external threading tool:

1. Countersink

2. Counterbore

Choose the correct answer

Name the types of plates:

1. Round, square (sliding), thread rolling

2. Hexagonal, spherical, face

3. Resistant, alloyed, hardened

4. Modular segment, profile

Choose the correct answer

What is sawing:

1. Variety of filing

2. Variety of lapping

3. Variety of scraping

4. Variety of fitting

Choose the correct answer

What is an attachment:

1. This is a locksmith operation for mutual adjustment of cutting methods for two mating parts

2. This is a locksmith operation for mutual adjustment by scraping two mating parts

3. This is a locksmith operation for mutual adjustment by grinding in two mating parts

4. This is a locksmith operation for mutual fitting by means of filing two mating parts

Choose the correct answer

What is scraping:

1. This is the final locksmith operation, which consists in scraping very thin layers of metal from the surface of the workpiece using a cutting tool - a lap

2. This is the final locksmith operation, which consists in scraping very thin layers of metal from the surface of the workpiece using a cutting tool - a scraper

3. This is the final locksmith operation, which consists in scraping very thin layers of metal from the surface of the workpiece using a cutting tool - a needle file

4. This is the final locksmith operation, which consists in scraping very thin layers of metal from the surface of the workpiece using a cutting tool - a rasp

Choose the correct answer

Name the types of scrapers according to the shape of the cutting edge:

1. One-sided, double-sided, three-sided

2. Flat, trihedral, shaped

3. Modular, profile, segment

4. Steel, cast iron, brass

Choose the right carrier

Name the types of scrapers by design:

1. Riveted and welded

2. Pin and wedge

3. Whole and composite

4. Keyed and splinted

1	2	3	4	5	6	7	8	9	10

11	12	13	14	15	16	17	18	19	20

21	22	23	24	25	26	27	28	29	30

31	32	33	34	35	36	37	38	39	40

Practical work.

Practice #33

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Markup.

Locksmith's workplace.

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The main types of plumbing operations

Markup.

Locksmith's workplace.

Topic 25. Basics of plumbing.

1. Locksmith work is the manual processing of materials, fitting parts, assembly and repair of various mechanisms and machines.

A workplace is a part of the production area with all the equipment, tools and materials located on it, which are used by a worker or a team of workers to complete a production task.

Locksmith workbench (Fig. 36) - the main equipment of the workplace. It is a stable metal or wooden table, the lid (tabletop) of which is made of boards 50 ... 60 mm thick of hardwood and covered with sheet iron. Single workbenches are the most convenient and common, since on multi-seat workbenches, when several people work at the same time, the quality of precision work is reduced.

Rice. 36 Single locksmith workbench:

1 - frame; 2 - countertop; 3 - vice; 4 - protective screen; 5 - tablet for drawings; 6 - lamp; 7 - shelf for tools; 8 - tablet for a working tool; 9 - boxes; 10 - shelves; 11 - seat

The workbench contains the tools necessary to complete the task. The drawings are placed on the tablet, and the measuring tools are placed on the shelves.

Under the tabletop of the workbench are drawers, divided into a number of cells for storing tools and documentation.

A protective screen made of metal mesh or durable plexiglass is installed on the workbench to retain pieces of metal that fly off during cutting.

Blanks, finished parts and fixtures are placed on racks installed in the area allotted for them.

2. Marking - the operation of drawing lines (rises) on the workpiece that determine (according to the drawing) the contours of the part and the places to be processed. Marking is used for individual and small-scale production.

Marking is carried out on marking plates cast from gray cast iron, aged and precisely machined.

Lines (risks) with a planar marking are applied with a scriber, with a spatial marking, with a scriber fixed in the thickness gauge collar. Scribers are made from steel grades U10 and U12, their working ends are hardened and sharpened sharply.

The center punch is intended for drawing indentations (cores) on pre-marked lines. It is made from steel grades U7, U7A, U8 and U8A.

The marking compass is used to draw circles, divide angles and apply linear dimensions to the workpiece.

3. The main types of plumbing operations.

Cutting is a locksmith operation, during which excess metal layers are removed from the workpiece with a cutting and impact tool, grooves and grooves are cut out, or the workpiece is divided into parts. The cutting tool is a chisel, a cross-cutting tool, and a hammer is a percussion tool.

Cutting is the operation of separating metals and other materials into pieces. Depending on the shape and size of the blanks, cutting is carried out with a hand saw, hand or lever scissors.

A hand saw consists of a steel solid or sliding frame and a hacksaw blade, which is inserted into the slots of the heads and secured with pins. A handle is fixed on the shank of the fixed head. A movable head with a screw and a wing nut is used to tension the hacksaw blade. The cutting part of the hacksaw is a hacksaw blade (a narrow and thin plate with teeth on one of the ribs) made of steel grades U10A, 9XC, P9, P18 and hardened. Hacksaw blades are used with a length (distance between holes) of 250-300 mm. The teeth of the blade are spread (bend) so that the width of the cut is slightly greater than the thickness of the blade.

Metal dressing is an operation in which irregularities, dents, curvature, warpage, waviness and other defects in materials, workpieces and parts are eliminated. Editing in most cases is a preparatory operation. Straightening has the same purpose as straightening, but defects are corrected in hardened parts.

Bending is widely used to give blanks a certain shape in the manufacture of parts. For manual straightening and bending, correct plates, straightening headstocks, anvils, vices, mandrels, sledgehammers, metal and wooden hammers (mallets) and special devices are used.

Riveting is a metalwork operation of joining two or more parts with rivets. Rivet connections are one-piece and are used in the manufacture of various metal structures.

Manual riveting is performed with a hammer, its mass is chosen depending on the diameter of the rivet, for example, for rivets with a diameter of 3 ... 3.5 mm, a hammer weighing 200 g is required.

Sawing is a locksmith operation in which a layer of metal is cut off from the surface of a part with files to obtain the required shape, size and surface roughness, to fit parts during assembly and prepare edges for welding.

Scraping is the operation of scraping thin layers of metal from the surface of a part with a cutting tool - a scraper. This is the final processing of precision surfaces (machine guides, control plates, plain bearings, etc.) to ensure tight mating. Scrapers are made of U10 and U12A steels, their cutting ends are hardened without tempering to a hardness of HRC 64...66.

Lapping and finishing - operations of surface treatment with especially fine-grained abrasive materials using lapping.

These operations achieve not only the required shape, but also the highest accuracy (5 ... 6th grade), as well as the lowest surface roughness (up to 0.05 microns).

Fitting and assembly work is the installation and dismantling work performed during the assembly and repair of machines. Various connections of parts performed during the assembly of machines are divided into two main types: movable and fixed. When performing locksmith and assembly work, a variety of tools and devices are used: wrenches (simple, socket, sliding, etc.), screwdrivers, punches, pullers, devices for pressing and pressing out.

Tools

Chisel are made of tool carbon steel U7A. The cutting part of the chisel has the shape of a wedge (Fig. 17, c), which is sharpened at a certain angle. The angle of sharpening (sharpening) of the chisel is chosen depending on the hardness of the material being processed: the harder the material, the greater the angle.

Figure 17

Kreutzmeisel(Fig. 17, b) is designed for cutting narrow grooves and keyways. It differs from a chisel in a narrower cutting part.

Hammers designed to strike when performing most plumbing operations (cutting, riveting, straightening, bending, chasing, assembling, etc.).

filing called a locksmith operation, in which layers of material are removed from the surface of the workpiece using a file.

By filing, they give the parts the required shape and dimensions, fit the parts to each other during assembly, and perform other work. With the help of files, planes, curved surfaces, grooves, grooves, holes of various shapes, surfaces located at different angles, etc. are processed.

Basic plumbing operations and their purpose

Locksmith operations are related to the processes of cold metal cutting. They are carried out both manually and with the help of a mechanized tool. The purpose of locksmith work is to give the workpiece the shape, size and surface finish specified by the drawing. The quality of the locksmith work performed depends on the skills of the locksmith, the tool used and the material being processed.

The metalworking technology contains a number of operations, which include: marking, cutting, straightening and bending metals, cutting metals with a hacksaw and scissors, filing, drilling, countersinking and reaming holes, threading, riveting, scraping, lapping and finishing, soldering and tinning , bearing casting, bonding, etc.

In the manufacture (processing) of metal parts by the locksmith method, the main operations are performed in a certain order, in which one operation precedes the other.

First, locksmith operations are performed to make or fix the workpiece: cutting, straightening, bending, which can be called preparatory. Next, the main processing of the workpiece is performed. In most cases, these are cutting and filing operations, as a result of which excess layers of metal are removed from the workpiece and it receives the shape, dimensions and state of surfaces that are close or coincide with those indicated on the drawing.

There are also such machine parts, for the processing of which the operations of scraping, grinding, finishing, etc., are also required, in which thin layers of metal are removed from the manufactured part. In addition, during the manufacture of a part, it can, if necessary, be connected to another part, together with which it is subjected to further processing. For this, drilling, countersinking, threading, riveting, soldering, etc.

File This is a multi-blade cutting tool that provides relatively high accuracy and low roughness of the workpiece (part) surface to be machined. Sawing allowances are left small - from 0.5 to 0.025 mm. The error during processing can be from 0.2 to 0.05 mm and in some cases up to 0.005 mm. A file is a steel bar of a certain profile and length, on the surface of which there is a notch (cutting). The notch forms small and sharply sharpened teeth, having a wedge shape in cross section. For files with a knurled tooth, the sharpening angle is usually 70 °, the rake angle ( y) - up to 16 °, clearance angle (a) - from 32 to 40 °. Single-cut files remove wide chips along the entire length of the cut. They are used when filing soft metals. Double-cut files are used when filing steel, cast iron and other hard materials, since the cross-notch crushes the chips, which facilitates the work.Files are made from steel U13 or U13A, as well as from chromium steel ShKh15 and 13X.After notching the teeth, the files are subjected to heat treatment.The handles of files are usually made of wood (birch, maple, ash and other species). files. For general plumbing work, general-purpose files are used. According to the number of notches per 1 cm of length, files are divided into 6 numbers:

Notched files No. 0 and 1 (bastard) have the largest teeth and are used for rough (rough) filing with an error of 0.5-0.2 mm.

Notched files No. 2 and 3 (personal) are used for fine filing of parts with an error of 0.15-0.02 mm.

Files with a notch No. 4 and 5 (velvet) are used for final fine finishing of products. Processing error -- 0.01--0.005 mm.

The length of the files can be made from 100 to 400 mm. According to the cross-sectional shape, they are divided into flat, square, trihedral, round, semicircular, rhombic and hacksaw.

For processing small parts, small-sized files are used - needle files. They are produced in five numbers with the number of notches per 1 cm of length from 20 to 112.

Processing of hardened steel and hard alloys is carried out with special needle files, on the steel rod of which grains of artificial diamond are fixed.

Improving conditions and increasing labor productivity when filing metal is achieved through the use of mechanized (electric and pneumatic) files.

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§ 21. Basic information about locksmith processing

Metal processing manually called metalwork. Locksmith work is divided into main, assembly and repair. The main plumbing work is called operations to give the details of the shape, size and surface condition specified by the drawing. Assembly locksmith work is carried out when assembling product units, when assembling machines and devices from individual units.

Repair locksmith work is carried out to maintain equipment in working order; they consist of corrections or replacement of failed parts and assemblies of machinery and equipment. Locksmith work includes the following basic operations: marking, cutting, straightening, bending, filing, scraping, lapping, drilling, threading, etc. There are special tools and devices for all these works.

markup serves to apply to the workpiece (forging, casting, etc.) marks (lines) indicating the boundaries of subsequent machining. Metal is marked on marking plates with various tools: scale rulers, scribers, thickness gauges, squares, compasses, center punches.

felling metal (sheet, strip, wire, etc.) is produced with chisels, cross-cuts using a hammer. In this case, the workpiece is installed on a plate or fixed in a bench vise.

cutting bars, pipes, strip metal are made manually with hacksaws. Larger workpieces are cut on powered hacksaws, cutting machines, as well as gas or electric arc cutting. For cutting sheet material with a thickness of up to 2 mm, hand and chair scissors are used, and for thicker ones, lever scissors with a mechanical drive are used.

edit used to correct irregularities, warping, leashes of sheet and bar material. Thin (up to 1 mm thick) sheets of tin, aluminum, red copper, brass and other soft materials are ruled on a stove with a wooden hammer, and thicker ones are ruled with steel hammers on a stove or on an anvil. Bent shafts and other large parts are straightened on presses.

bending thin metal sheets and rolled bars are produced in a vise with uniform blows of a wooden hammer, and thicker ones - with a steel hammer. To speed up the bending process, special devices are used.

Filing is the processing of workpiece surfaces with a file to eliminate the irregularities of the previous processing and achieve the necessary accuracy in size, shape and surface roughness.

Scraping is used to obtain the surface roughness required by the operating conditions or for a snug fit of the mating surfaces of machine parts. Scraping is the final operation (when processing the guide surfaces of bearing shells, machine and machine frames) and is carried out with a special cutting tool - a scraper.

Lapping are performed with hard grinding powders, which are applied to special laps made of mild steel, gray cast iron, copper, hardwood and other materials. The shape of the lap must match the shape of the surface to be treated. By moving the lap with grinding powder over the surface to be treated, a very thin (0.001-0.002 mm) layer of irregularities is removed from it, due to which a tight contact of the mating parts is achieved.

drilled small and shallow holes drilled with hand, electric and pneumatic drills. Large and deep holes are drilled on machines.

Threading during plumbing work with taps and dies. Taps are used for cutting internal threads, and dies are used for external threading.

When assembling parts and assemblies of machines, the same locksmith operations are used.

Control questions

1. List the main properties of metals and alloys.

2. What is gray cast iron (composition, properties)?

3. What is ductile iron (composition, properties)?

4. What is steel and what are its properties?

5. Specify the main types of thermal and chemical-thermal treatment and their purpose.

6. Provide basic information about non-ferrous metals and their alloys.

7. What are the main types of metal processing and their characteristics?

8. What welding methods are used in industry?

9. What are the main operations used in locksmith processing?

What is the name of the method of performing a plumbing operation. General information about locksmith work. Topic. Basics of metalworking

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§ 21. Basic information about locksmith processing