For the most rational organization of work on maintenance, repair and diagnostics of vehicles, its units and systems, various technological maps are drawn up.

Based on these technological maps, the volume of work on technical impacts is determined, and the work (operations) is distributed among the performers.

Any technological map is a guideline for each performer and, in addition, serves as a document for technical control of maintenance or repair.

The technological map is compiled separately for the type of service (EO, TO-1, TO-2), and within the type of service - by element.

When developing technological processes, it is necessary, taking into account the volume of work performed and their repetition, to strive for the most complete and economically justified mechanization, the complete reduction of resource, energy and labor costs, and the facilitation of manual labor.

The optimal variant of the technological process of vehicle maintenance and repair allows you to obtain the following advantages:

High labor productivity and quality of work;

Eliminate omissions or repetitions of individual operations and transitions;

Rational use of mechanization means;

Carry out the required organization and arrangement of workplaces.

2.2 Operation card to-2 of the KrAZ - 250 vehicle

The total labor intensity of TO-2 is 16 people ∙ hour (960 people ∙ min)

Map No. 1. Control and inspection work.

Labor intensity - 18.65 people ∙ min

Order number	Name of operations	Location of operations	Number of places or points of service	Tools and equipment	Repeatability factor	Labor intensity, person ∙ min	Specifications and instructions
	Inspect the vehicle and at the same time check the condition of the cab, license plates, platform, seats, windows, glass and door seals, trim, tail surfaces, cabin lid ventilation hatches and paint						Cabin glass must be intact. License plates must be securely fastened and their condition must comply with traffic regulations. There should be no noticeable damage to the car's painted surfaces. The platform sides must be tightly locked and held closed and must not be cracked or broken.
	Check the serviceability and fastening of cab door locks, platform side locks, windshield washer devices, rear view mirror holders						Cabin locks and platform side locks must be in good working order. The windshield washer water pump must be securely fastened; leakage of washing liquid is not allowed. Mirrors must be intact, securely mounted on brackets and correctly adjusted
	Check the condition and operation of the radiator shutter drive, windshield wipers and window lifters	In the cockpit					The radiator shutters should open and close without jamming. The wiper blades must fit snugly along the entire length of the edge to the surface of the windshield and move without jamming or stopping. Window regulators should operate smoothly without jamming.
	Inspect the vehicle for obvious damage
	Check the operation of lighting, alarm, and sound signal devices	In the cockpit					Lighting devices should shine, and alarms and sound signals should work properly
	Check the operation of the windshield wipers, washers and heaters (in winter), and the presence of sun shields						Windshield wipers and washers must work
	Check the operation of instrumentation			Visually, device E-204			The readings of the control and measuring instruments must correspond to the given engine operating mode. If there are deviations in the instrument readings from the actual ones, carry out an additional check using the E-204 device

PAGE \* MERGEFORMAT 32

I . Introduction ……………………………………………………………………………… 1

II . Main part………………………………………………………3

2.1. Main damage to the body………………………………………………………. 3

2.2. Preparing the body for repairs…………………………………….. 3

2.2.1. Acceptance of the body for repairs……………………………………………………… 3

2.2.2. Body disassembly……………………………………………………… 7

2.2.3. Removing paint and varnish coatings and cleaning bodies of products

Corrosion………………………………………………………………………………… 9

2.2.4. Flaw detection of the body…………………………………………………………………... 10

2.3. Accident damage to the body…………………………………... 11

2.4. Damage resulting from the use of bodies……….. 16

2.5.1. Body repair methods…………………………………………………………… 18

2.5.2. In-line method of repair and assembly of bodies……………………… 18

2.6. Body repair methods………………………………………………………21

2.6.1. Repair by replacing damaged parts……………………………. 21

2.6.2. Mechanical straightening of deformed panels and openings

Impact………………………………………………………. 22

2.6.3. Straightening using heat………………………………………. 27

2.7. Restoration of non-metallic parts…………………………. 28

2.8. Repair of main mechanisms and body equipment…………….. 29

2.9. Body assembly………………………………………………………. 31

III . Occupational safety and health………..…………………….. 33

3.1. Basic provisions on occupational safety……………………….. 33

3.2. Requirements for technological processes………………………….. 34

3.3. Requirements for working premises…………………………………….. 35

IV . Conclusion……………………………………………………………... 36

V . List of references……………………………………………………….. 37

I.Introduction.

One of the reserves for increasing the country's car fleet is organizing car repairs at the proper level. The need and expediency of repairs are determined primarily by the fact that during long-term operation, cars reach a state where the costs of money and labor associated with maintaining them in working condition exceed the income received from their further operation. This technical condition of cars is considered to be extreme and is due to the uneven strength of their parts and assemblies. It is known that it is almost impossible to create a machine of equal strength, all of whose parts would wear out evenly and have the same service life. Therefore, repairing a car, even just by replacing some parts that have a short lifespan, is always advisable and justified from an economic point of view.

The main source of economic efficiency in car repair is the use of the residual life of their parts. About seventy percent of car parts that have completed their service life before repair have a residual life and can be reused either without repair or after minor repair work.

One of the main components of a car is the body. The bodies of cars and buses are also the most difficult units to manufacture. The labor intensity of manufacturing a body, for example a passenger car, is 60% of the total labor intensity of manufacturing a car. The body also includes the tail: radiator lining, hood, fenders, trunk lid. The rigidity and strength of the body increase the service life of the vehicle. Failure of the body practically means failure of the car.

For the rolling stock of road transport in the public sector, the task of maintaining it in good condition, as well as repairing components and assemblies, is successfully implemented by a clearly regulated system of control and periodic technical interventions at road transport enterprises (ATEs) and at auto repair plants (ARFs). The current policy of concentrating car repairs in production associations of the automotive industry will make it possible to consolidate and specialize enterprises. At large specialized car repair enterprises, conditions are created for the widespread use of the most advanced technological processes and modern high-performance equipment. This general direction in the development of car repair production will lead to a sharp increase in the quality of car repairs and the fullest realization of its economic advantages.

Currently, the fleet of cars owned by citizens has grown sharply. Maintaining this fleet in working order is possible mainly through the widely developed car service system. A whole network of service stations (STOs) has been built and put into operation throughout the country, where maintenance and repair of personal vehicles are carried out.

II . Main part.

2.1 Main body damage

During operation, elements and components (assembly units) of the body experience dynamic loads from bending in the vertical plane and torsion, loads from their own weight, the weight of cargo and passengers. The body and its components are also affected by significant stresses resulting from its vibrations when moving over uneven surfaces, shocks and impacts during collisions, as well as due to errors in balancing of rotating components, displacement of the center of gravity in the longitudinal and transverse directions. These stresses cause the accumulation of fatigue and lead to destruction of body elements.

In the bodies of cars coming in for repairs, there are: damage that appears as a result of increasing changes in the condition of the body; these include natural wear and tear that occurs during normal technical operation of the vehicle, due to the constant impact on the body of such factors as corrosion, friction, elastic and plastic deformation, etc.; damage, the occurrence of which is associated with human actions, design defects, violation of body maintenance standards and technical operation rules, and also caused by transport incidents (accidents).

2.2 Preparing bodies for repair

2.2.1 Acceptance of bodies for repair

Bodies received for repair must meet the requirements of the technical specifications for the delivery and repair of vehicles with the appropriate body design. The technical specifications provide for permissible damage to the body and its certain completeness. Incomplete bodies or bodies requiring repairs, the volume of which exceeds the maximum allowed by technical conditions, as a rule, are not accepted for repair. Usually they check the presence of doors, interior seat upholstery, glass with frames and frames, windshield, turning and rear windows, lampshades, interior and exterior handles, decorative trims, mechanisms: locks, raising and lowering windows, heating and ventilation equipment, and windshield wipers. External body washing is carried out in a room specially equipped for this purpose, usually before disassembling the car into units. After an external wash, the body is subjected to preliminary control, during which a thorough external inspection of components and parts that must be removed from the body during its major repairs (internal body upholstery, glass, fittings, decorative linings, etc.) is carried out to determine their condition and the feasibility of repair. . The main goal of preliminary control is not to clutter production premises with unusable (scrap) parts. Then remove from the body all components and parts that cover the body from the inside and outside, as well as all units of the vehicle chassis from the supporting structure body. To thoroughly (finally) clean the underbody from dirt, it is washed a second time.

Assemblies and parts removed from the body, depending on their condition, are sent to the appropriate departments for storage, repair or to a scrap warehouse, and chassis units are sent to the assembly and repair department. The old paintwork is removed from the body. The body, disassembled in this way and cleared of the old coating, undergoes a detailed inspection, during which the nature of the damage is revealed, the repair procedure is outlined, and the labor intensity of the repair work is determined. The results of preliminary and final inspection are included in the inspection sheet, which is the main document determining the condition of the body before repair. In the control and sorting sheet, three groups of parts are noted: suitable, requiring repair, requiring replacement (unusable). A copy of the statement goes to the foreman of the corresponding repair area, and the original goes to the accounting department of the repair company to determine the cost of body repairs.

The body then goes to the repair area, where the damage is repaired.

Schemes of technological processes for repairing bodies of cars, buses and truck cabins differ from each other in the presence of various equipment and mechanisms on them, as well as damage characteristic of each body structure and methods for eliminating them.

Figure 5 General flow diagram of the body repair process

2.2.2 Body dismantling

Body disassembly can be partial or complete, depending on the required repairs and the condition of the body. Partial disassembly is carried out when the body as a whole is in good condition and only individual parts that are damaged as a result of wear, loosening or an accident require repair. Complete disassembly is carried out, as a rule, during a major overhaul of the car and when most of the body components need repair.

Body components can be properly disassembled only with strict adherence to a certain technological sequenceefficiency, eliminating the possibility of breakage and damage to parts. Therefore, the disassembly order is established by the technological process, which is developed for each body type.

When dismantling bodies and tails, labor-intensive work involves unscrewing rusted bolts, nuts and screws, removing rivets, and separating spot-welded panels. To remove fasteners that cannot be unscrewed, you can use one of the following methods: heat the nut with a gas flame; this method is very effective and works quickly; after heating, the nut usually comes off easily; bite off the bolt and nut with pliers or cut with a hacksaw; cut off the nut with a chisel; drill a hole in the bolt head with a diameter equal to the diameter of the bolt rod; after drilling, the head falls off, and the bolt shaft with the nut is knocked out with a beard. This method has been successfully used for turning round head bolts connecting wooden parts; cut off the head of the bolt or screw with a gas flame and knock the rod with the nut out of the socket.

Currently, to make it easier to unscrew rusted bolts and nuts, special chemical compounds are widely used, which, when applied to bolted joints, partially remove corrosion products on the threads, and due to their good penetrating ability, lubricate the threads between the bolt and nut and thereby facilitate the dismantling of the threaded joint. Typically, such compositions are produced in aerosol packaging and applied by spraying.

In screws that cannot be removed due to jamming or wear of the head slot, the head should be drilled, and then, after removing the part, unscrew or pull the screw out of the wood. Rusted door hinge screws are heated with a gas flame, after which they can be easily removed. The riveted seams are made in such a way as not to damage the disassembled panels if they cannot be replaced. Parts strengthened by spot welding are cut off with a sharp thin chisel or welding points are drilled through the top sheet of the panel from the non-facial side of the body. Particular care is required when disassembling fragile and easily damaged parts. Parts subject to scrapping can be removed in any way that speeds up disassembly, even to the point of damaging them, if they cannot be removed, but provided that the usable parts associated with them are not damaged.

When completely dismantling bodies, the scope of work and the order in which they are performed largely depend on the structure of the body and on the number and nature of damage. The sequence of body disassembly comes down mainly to the removal of seat cushions and backrests, internal equipment, handles, handrails, holders, chrome fittings and decorative trims, finishing frames, armrests, lampshades, internal partitions, interior upholstery, various mechanisms, body glass, electrical wiring, pipes heater and other parts and assemblies installed inside the body. For ease of disassembly, the body is mounted on a special stand.

2.2.3 Removing paint and varnish coatings and cleaning bodies from corrosion products

Old paintwork can be removed mechanically using sandblasting (shot blasting) machines or mechanized hand tools, chemical treatment with special removers and alkaline solutions.

Shot blasting and power cleaning removes rust and scale at the same time as the paintwork. The most common abrasive material for shot blasting metal surfaces is metal shot, produced by industry with a grain size of 0.2 - 0.3 mm. To clean body and tail panels made of sheet steel 0.8-1 mm thick from the old coating and obtain the necessary roughness, the optimal angle of inclination of the shot jet to the surface being treated should be 45°, and the air pressure should be 0.2 - 0.3 MPa. The roughness of the treated surface should not be more than 20 - 30 microns, which ensures high quality of the newly applied protective coating.

To carry out shot blasting, a mobile shot blasting machine with a hand gun is used. This device provides for automatic regeneration of abrasive shot and its supply to the shot blasting gun.

Various installations are used to remove corrosion products manually and mechanically. Of these installations, the needle mill is of greatest interest. The needle mill is made from straight pieces of high-strength wire with a certain packing density. Such a tool can cut off a layer of rust, scale, and metal 0.01-1 mm thick. Manual mechanized tools for cleaning surfaces and removing paint coatings also include grinding machines MSh-1, I-144, and grinding machines ShR-2, ShR-6. This cleaning method is used for small volumes of work, since it does not provide the required quality and productivity of work.

To remove coatings chemically, various removers are used. Removers are applied to the surface by spraying or brushing. After a few hours, the coating swells and is removed mechanically, and then the surface is washed with water.

2.2.4 Flaw detection of bodies

After removing the old paintwork, the body is subjected to careful control in order to reject unusable parts, select suitable ones, and determine the type and scope of repair work. The quality of the repair largely depends on the adopted method of flaw detection and the thoroughness of its implementation. To detect defects in the body shell, as well as to control newly manufactured parts and welds, non-destructive testing methods are used.

The technical condition of the body is usually checked by external inspection of the surface of parts with the naked eye or using simple magnifying glasses. This method makes it possible to detect surface cracks, corrosion, deformations, etc. Measurement with special devices and templates makes it possible to detect deviations in the geometric dimensions of parts from the original ones (distortions, deflections, etc.).

However, an external examination can only detect large damage visible to the eye. In some places of the load-bearing elements of the body, hairline cracks appear, which can be detected using special methods. Methods based on the molecular properties of a liquid are called capillary methods (penetrating liquid methods). The most common are kerosene and fluorescent methods. Kerosene, having good wettability and low surface tension, easily penetrates into leaks. The essence of this method is that the area being examined is moistened with kerosene and wiped dry or dried with a stream of air. Then this place is covered with an aqueous solution of chalk. Due to the absorption of kerosene by the chalk, a grease mark appears on the chalk surface, repeating the geometry of the detected crack. For this flaw detection method, you can use industrially produced penetrating and developing compositions based on dyes and enamels. The paint method can detect cracks with a width of 0.005 mm and a depth of up to 0.4 mm. To correctly select the method and scope of repair of a car body made of thin sheet steel, the depth of corrosion destruction should be determined during flaw detection of the body. For this purpose, gamma thickness gauges are used, based on measuring the intensity of gamma radiation. The device allows you to measure sheets with a thickness from 0 to 16 mm, while the measurement time does not exceed 30 s.

2.3 Accident damage to bodies

The most severe damage is caused by frontal collisions with the front part of the body at an angle of 40-45 degrees or from the side between two vehicles moving in the same direction. In such collisions of the car, the front part of the body is especially severely destroyed, while large loads in the longitudinal, transverse and vertical directions are transferred to all adjacent parts of the frame and especially its power elements.

In the event of a frontal collision of a car (Figure 1), the front part of the body in the area of ​​the left front fender, side member and left headlight is deformed by the front panel, fenders, hood, mud flaps, front side members, wind window frame and roof. This can be seen in the figure along the dotted lines. At the same time, invisible deformation is transferred to the front, center and rear pillars on both sides, the front and rear left doors, the left rear fender and even the rear trunk panel.

Figure 1 Frontal impact

Load distribution directions and possibleWhen a car is hit in the front part of the body at an angle of 40 - 45° (Figure 2), the front fenders, hood, front panel, mudguard, and front side members are damaged.

Figure 2 Left front collision at 40-45° angle

When there is a side impact with the front part of the body (Figure 3), in the area where the front panel meets the front part of the spar and the left wing, both front wings, the front panel, the spar mud flaps, and the hood are deformed. In addition, under the influence of tensile forces, the opening of the left front door is broken, and under the influence of compressive forces, the opening of the right door and the side of the left front door are deformed. At the same time, significant force overloads are transmitted to the front and central pillars, causing them to deviate from their original position.

Figure 3 Side collision with the front end at the junction of the front panel with the wing and the left wing

When there is a side impact (Figure 4) with the A-pillar on the left side, the left A-pillar, wind window frame, roof, floor and front floor side members, front panel, hood, fenders, mudguards, front side members are significantly deformed. In this case, the front part of the body is moved to the left; the threshold and the upper part of the right sidewall perceive tensile loads, and the central and rear pillars - compressive loads.

Figure 4 Left A-pillar side collision

The presence of invisible deformations in the power elements of the body can be determined by taking measurements: by the presence of distortions in the front parts, protrusions of one part relative to another, unacceptable gaps in the interfaces of openings with doors, hood, trunk lid.

From the above examples it is clear that as a result of accidents, deformation spreads along the associated elements of the body, causing a violation of the geometry of its openings and base points of the floor. Such damage, which requires replacing most of the parts and complex repairs, can be eliminated only with the help of special equipment, using hydraulic and manual straightening methods in repair operations, followed by control of the body geometry.

2.4 Damage caused by the use of bodies

In metal bodies there are also less significant damages that worsen their appearance.

Dents appear as a result of residual deformation upon impact, improper repair, as well as due to certainproper assembly of body parts. Dents can be simple, easy to repair, or complex - with sharp bends and folds, and can be located in places that are difficult to reach for repair.

Cracks are a common type of damage. They can appear in any part of the body as a result of metal overstress (impacts, bends), as well as due to weak connections of components and parts and insufficient structural strength.

Tears and holes can be divided into simple ones, which take on the appearance of a normal crack after straightening the metal, and complex ones, which require patches to be applied when repairing the damaged area.

Breaks in body parts are characterized by the size of the torn part of the panel or tail. Large breaks are often eliminated by installing new inserts with a complex profile, and sometimes the part is completely replaced.

Stretched metal surfaces are distinguished by their location: on the panel surface in the form of a bump and in the flanges of parts (stretched sides and edges).

Corrosion in its external manifestation can be uniform, when the metal is destroyed evenly over the entire surface, and local, when the metal is destroyed in individual areas; This form of corrosion is detected by dark spots or deep black spots on the metal and is more dangerous, since the metal can be destroyed in a short time, creating through holes.

Failure of welded joints occurs in parts assemblies that are connected by spot welding and in continuous body welds.

Failure of riveted welds is the result of loosening or shearing of rivets and wear of bolt and rivet holes.

Deflections, distortions and twisting usually occur as a result of emergency loading. Distortions can be inter-node and in the plane of one node or part (distortion in the body opening for the door, distortion in the door itself, deflection in the floor sills).

Wear of holes and rods occurs as a result of rolling friction (axles and holes in door hinges) or loosening of the assembly with rivets or bolts; wear of surfaces due to systematic load applied to the surface, for example when transporting bulk abrasive cargo in the bodies of dump trucks.

Structural defects in body components often lead not only to damage, but also complicate their repair, and sometimes the performance of repair operations, up to the need to replace the damaged component with a new one. Structural defects in the body, which complicate its repair, occur mainly because automobile factories do not fully take into account the requirements of motor transport and auto repair enterprises for body design.

2.5.1 Body repair methods

Repair and assembly of bodies is carried out using two methods - stationary and in-line. With the stationary repair method, the body is installed on a stand for the duration of the repair. The worker, having completed work on the body at one stand, moves to another. With the flow method, during the repair process, the body is sequentially moved through specialized work stations, where a certain amount of work is performed in a limited time. Practice has shown that this method is the most effective, speeds up and improves body repairs and has a number of advantages compared to stationary ones.

2.5.2 In-line method of body repair and assembly

The main advantages of the flow method are the ability to place tools and devices in close proximity to the bodies being repaired in the sequence of their use, and for workers to quickly perform operations provided for by the process with minimal movements and labor costs; in increasing the repetition of operations and the specialization of workers in certain types of work, which makes it possible to achieve accuracy and perfection in their implementation, and increase labor productivity.

The multitude of repair and assembly operations performed on the body does not allow them to be stretched into one line geographically and alternated in time sequentially one after another. Consequently, a slow rhythm of the production line and maximum combination of repair and assembly operations at one workplace is necessary so that the length of the flow line does not exceed the length of the production premises. When choosing the number of work stations on a production line, it is necessary, in addition to the length of the assembly department tracks, to also take into account the staffing level, strength, capacity of subsidiary departments and sections, as well as the need to arrange bodies at certain intervals, allowing the necessary work to be performed at each station.

Work on repair and assembly of bodies can be carried out on-line with moving or stationary bodies. The production line with fixed bodies is serviced by repair teams rhythmically moving along the work front from stand to stand, at each of which they perform the required operations. On a production line with moving bodies, the body moves along the front of the work, sequentially undergoing all the operations that are performed at a specific work station. The body remains at each post until the completion of all work planned for this post, and then moves to the next post (stand). This type of flow is the most productive.

The most rationally organized repair is in which the maximum possible number of parts and assemblies of the body (cabin) that require repair or replacement are repaired in advance in the relevant departments of the body shop or replaced with ready-made spare parts. This reduces to a minimum the number of repair operations on the production line and, consequently, the duration of the production cycle.

Repair and assembly of bodies are carried out on two parallel lines. On the first line - body washing, removal of old paintwork, preliminary and final inspection, disassembly, repair and assembly of the body before painting; on the second - installation of units, components and parts on the body and its final finishing after painting. This process design has proven itself in practice, since it allows for the most efficient use of production space. The number of disassembly stations, as well as posts for all other types of work (repair, assembly), depends on the plant program.

To install and move car bodies and cabins in the painting department, various methods are used: bodies (cabins) can remain on trolleys until the entire complex of painting work is completed; when entering the painting department, the body (cabin) is installed on stationary stands (roller conveyors), the size of which does not exceed the overall dimensions of the body (cabin); the cabins are suspended from the trolleys of an overhead conveyor or monorail mounted above all preparatory stations and passing through the painting and drying chambers.

The areas for dismantling, repair and assembly of bodies are equipped with the equipment and auxiliary devices required for work, designed to create convenience when using hand-held power and pneumatic tools, storing components and parts removed from the body or to be installed on it, etc.

2.6 Body repair methods

2.6.1 Repair by replacing damaged parts

Let's consider the processes of replacing the rear wing of a car after general disassembly of the body, since this type of repair is most often found in the practice of repair enterprises.

Figure 6 Replacing the rear wing of a passenger car: a - marking the wing cut line, b - cutouts on the flanges

Replacement of the rear wing welded to the car body is carried out as follows. Mark a cut line with a pencil or chalk along the entire perimeter of the old wing in such a way as to leave stripes 20 - 30 mm wide on the front of the wing, along the arch of the wheel opening and the top of the wing - to its flange (Figure 6a). The old wing is carefully cut out according to the markings using a grinding machine with a cutting abrasive wheel or a chisel and scissors for cutting sheet metal, so as not to damage the internal parts of the body attached to the body under the wing at the cut-out points. If, after removing the old fender, the flanges of its upper part remaining on the body do not allow the new fender to be carefully adjusted to the place where it is attached, these flanges are removed. Drill out the contact welding points from the side of the welded flange to the depth of its thickness and disconnect the flange from the body using pliers or a thin sharp chisel. To drill out weld points, use a drill with a diameter of 6 mm, sharpened at an angle of 150 - 160°.After trimming the wing, the surfaces of the flanges to which the new wing is to be welded are carefully trimmed and cleaned to a metallic shine. On the latter, cutouts with a radius of 5 -7 mm are made in increments of 40 - 50 mm along the entire perimeter to be welded (Figure 6b). Install and adjust the new wing to the mounting location and press it tightly using a clamp. Welding is carried out only along the edges of the bites in the following sequence: the upper front part is welded in three or four places, then the lower rear part from above in the area of ​​the lantern, and then along the arch of the wheel opening, etc. until the final welding of the wing. During the welding process and after its completion, the weld seam is hammered using a support, and then the seam is thoroughly cleaned to a metallic shine.

2.6.2 Correction of deformed panels and openings by mechanical action

As a rule, dents in body panels and tail panels, where the metal is not stretched after an impact, are leveled by squeezing or pulling the concave section until it is given the correct radius of curvature.

When the metal is greatly stretched, bulges are formed that cannot be corrected by straightening. Correction of the bulge can be done in a cold or heated state. Removing bulges in a cold state is based on stretching the metal in concentric circles or radii from the bulge to the undamaged part of the metal (Figure 7). This creates a smooth transition from the highest part of the bulge to the surrounding surface of the panel.

Figure 7 Method for straightening (b) bulges in body panels (a) without heating:

1 - bulge, 2 - panel, 3 - sections of the panel to be stretched by a hammer blow, 4 - radius of curvature of the panel after correcting the bulge, 5 - diagram of the direction of hammer blows (indicated by arrows)

The significant stretching of the metal that occurs when removing a bulge by straightening in a cold state increases the true surface of the metal in the area being repaired. As a result, the corrosion resistance of the metal deteriorates. Therefore, it is recommended to straighten uneven (wavy, small concave surfaces) metal body panels and tail surfaces mechanically by smoothing them with special devices, squeezing or pulling them using the devices listed below, and straighten bulges using heat.

To straighten hard-to-reach places, curved blade supports are used (Figure 8a), the end of which can be inserted between the inner and outer body panels through gaps or mounting hatches (Figure 8b).

Figure 8 Supports(A) for straightening areas covered by internal panels and a diagram for straightening the trunk lid with their help (b): 1 - support,2 - inner panel, 3 - dent, 4 - straightening hammer, 5 - outer panel

Figure 9 Straightening minor dents on panels (roof, doors, hood, etc.)

To straighten hard-to-reach places, curved blade supports are used (Fig. 8a), the end of which can be inserted between the inner and outer body panels through gaps or mounting hatches (Fig. 8b).

The straightening of minor dents on the roof panels, doors, hood, trunk, fenders and other front panels and the techniques for its implementation are shown in Figure 9.

Repairing dents on bodies with a rounded (oval) front surface (Figure 10) always starts from the periphery of the dent and moves towards its center.

Figure 10 Sequence (1-9) of repairing dents on body parts with a rounded (oval) front surface

In some cases, minor deformations in panels can be eliminated using a clamping lever. Techniques for working with this tool, as well as with a hammer and a clamping lever, are shown in Figures 10, 11.

Figure 10 Correction of a deformed area using a clamping lever

Figure 11 Repairing dents using a hammer and a clamping lever

When using a special straightening hammer (notched) and a support anvil for straightening small deformed areasthe metal “does not float”; its length is restored to its original shape and size.

To correct distortions in the windshield opening and doorway, hydraulic and screw braces are used. Correcting the deflection in the roof using tension is shown in Figure 12a,and the distortion in the doorway is shown in Figure 12b.

Figure 12 Correcting the deflection in the roof (a) of the body and eliminating the distortion in the doorway (b)

2.6.3 Heat straightening

The essence of the thermal straightening method is that the heated section of the panel, during the process of thermal expansion, encounters resistance from the surrounding cold metal. In progresscooling, the bulge decreases due to the fact that the heated areas around it, cooling, produce a contracting effect. As a general rule, the heating zone should be located as close to the top of the bulge as possible. Heating is carried out in spots or stripes using an oxygen-acetylene burner to a temperature of 600 - 650°C. Spots up to 30 mm in diameter are oriented along the long sides of the bulge. Heating begins at a more rigid area and moves to a less rigid one. The distance between the centers of the spots is 70 - 80 mm.

If the shape of the bulge approaches spherical, then heating is carried out by intersecting strips or a strip located along the slopes of the bulge. Each subsequent strip is heated after the previous one has completely cooled. If there is free access to the bulge from the outer and inner sides of the panel, then to speed up straightening you can combine heating with mechanical action. In this case, the most stretched part is heated in small spots and the blows of a wooden hammer around the heated spot “drive” the excess metal into this spot (Figure 13).

Figure 13 Scheme for straightening bulges in a heated state: 1 - approximate direction of hammer blows, 2 - heated spot, 3 - support,

4 - panel

2.7 Restoration of non-metallic parts

Non-metallic materials used in bodies include various plastics for decorative finishing of body interiors, as well as upholstery materials.

Damaged parts of bodies and cabins, for the manufacture of which plastics are used, are replaced with new ones during the repair process, since their manufacturing technology is simple and economical. Parts whose repair is feasible and economically justified are usually restored by gluing. The choice of adhesive for joining plastic materials depends on the chemical nature of the material, operating conditions of the adhesive joint and the technology of its application. For the manufacture of parts from plastics, etrol, polyamide, organic glass, nylon, etc. are used.

The gluing technology consists of the usual operations of surface preparation, applying glue and holding the adhesive composition under pressure. Parts made from etrol are glued with acetic acid, which is applied to the surfaces to be glued, and then they are connected under slight pressure and kept for 0.75-1 hour.

For gluing polyamides, solutions of polyamides in formic acid or formic acid are used. Plastic parts based on thermosetting resins are glued together with glue without temperature, moisture or chemical solvents. Tears in upholstery made of leatherette or polyvinyl chloride film, reinforced or not reinforced with a mesh of synthetic fibers, are eliminated by gluing the inserts with polyamide glue PEF-2/10. Gluing is carried out at room temperature, followed by exposure under pressure for 1-1.5 hours. To glue the new upholstery to the cardboard, 88NP glue is used. The material for sewing new upholstery parts is cut according to markings or templates using an electric knife. The upholstery parts to be joined are sewn with a certain stitch pitch at a given distance from the edges using a single or double seam from the non-facing side of the upholstery. To increase the strength of the connection of the upper upholstery of the seat cushion, overcast seams with edging are used. The stitched upholstery should not have loose tightness, distortions, wrinkles, folds or damage on the front side. To assemble the seat cushions and backrests, a pneumatic stand is used, which allows the springs of the cushions to be compressed to ensure tension in the material.

2.8 Repair of main mechanisms and body equipment

The main mechanisms and equipment of bodies and cabins include locks, window lifters and glass fastening mechanisms, seat frames, door and hood hinges, heater heating system, etc. All parts of body mechanisms are relatively simple in design and their repair is reduced to performing simple plumbing and welding operations.

Existing cracks in the housings are welded, worn working surfaces are repaired by surfacing or processing to repair size. Body parts with broken parts are rejected. Broken springs and springs that have lost their elasticity are replaced with new ones. Broken screws in threaded connections are removed by turning them out, if it is possible to grab them by the protruding part, or by drilling a hole with a drill of a smaller diameter than the screw. A square rod is inserted into this hole, with the help of which the rest of the screw is removed. After removing the screw, the threads in the hole are driven with a tap. If the thread in the hole is damaged, then weld the hole, clean off the metal deposits from the weld flush with the base metal of the body, drill a hole for the thread of the required size and cut a new thread. Loose rivets are tightened, and those that cannot be tightened are cut down and replaced with new ones. Destroyed cuffs, seals, O-rings and gaskets are replaced with new ones. Minor deposits of corrosion on the surface of parts are cleaned with sandpaper or a scraper and lubricated with kerosene. In case of deep traces of corrosion, damaged parts are replaced with new ones.

During major repairs of bodies and cabins, the locks are completely dismantled. All parts are thoroughly washed in a bath with kerosene and wiped dry. After repairing or replacing parts, the lock is assembled and adjusted.

The technology for repairing window regulators consists of completely disassembling them, washing them, checking them, replacing unsuitable parts with new ones, assembling them and then adjusting them. Damaged door glass is replaced with new one.

The most typical defects of seat frames include scratches, peeling of the chrome coating and corrosion on the surface of the upper part of the frame, deformation of the upper part of the frame, cracks and breaks in bends and soldering areas, bent or broken legs of the frame's fastenings to the floor and breakage of the backrest mounting brackets. To restore the decorative coating, the chrome parts are removed and a new coating is applied. Broken soldering areas are cleaned of old solder and other contaminants and soldered again. Parts with cracks, breaks and other damage are separated by heating with a gas burner and replaced with new ones. New parts of the frame are made from seamless pipe, the outer diameter of which is 25 mm and the wall thickness is 1.5 mm.

Repair of door and hood hinges consists of eliminating bents by straightening with a hammer on the plate, cracks and wear, welding followed by machining, and restoring holes to repair dimensions. Hinge parts that have broken parts are replaced with new ones.

2.9 Body assembly

The body assembly process usually consists of assembly before painting and general assembly after painting. Fundamentally, the process of general assembly after painting the body during its repair is no different from assembling a new body; only the organizational forms of assembly and the ratio of labor intensity of individual types of work change. The assembly of the body after a major overhaul must be carried out in the same sequence and with the same care as the assembly of a new body.

A characteristic feature of the assembly is that all the main shortcomings of previous technological operations are revealed here. If they are made with deviation from the technical specifications, then additional processing, adjustment and various kinds of finishing touches are performed, which affect the labor intensity and quality of assembly.

When assembling bodies, serious attention is paid to the selection of tools and fixtures. In addition to universal tools and devices that can be used in any operation corresponding to their purpose (wrenches, screwdrivers, etc.), special tools designed to perform one very specific operation are also widely used. The use of special devices or tools simplifies and facilitates the assembly process.

Assembly of any body cannot be carried out in any order. The assembly sequence is determined primarily by the design of the assembly being assembled, as well as the required division of assembly work. For clarity, it is customary to depict assembly diagrams in such a way that the corresponding components and parts are placed in the order of their introduction into the assembly process.

Depending on the quality of the repair, the accuracy of manufacturing of individual components and body parts and the amount of fitting work, three main types of assembly are distinguished: according to the principle of complete interchangeability, according to the principle of individual fitting and according to the principle of limited interchangeability. Assembly on the principle of complete interchangeability is used mainly in mass and large-scale production. In small-scale production, and especially in single production, the principle of complete interchangeability is not economically justified and therefore it is applied only in individual cases. Assembly according to the principle of individual fit, the purpose of which is to give the part exact dimensions or one or another geometric shape, is carried out by fitting the parts being connected to each other. This operation is usually very complex and time-consuming, so at advanced auto repair plants, assembly based on the principle of individual fit is gradually being replaced by more advanced assembly based on the principle of limited interchangeability.

The most common types of fitting work during body assembly are work related to the installation of parts and assemblies removed from the body and undergone repair or newly manufactured; filing; drilling and deployment of holes in place; thread cutting; stripping; flexible. Mechanization of fitting work during assembly is carried out mainly through the use of universal and specialized tools with electric and pneumatic drives.

Assembly of bodies prior to painting usually involves a significant amount of fitting work and is carried out in the body repair area. Before painting, passenger car bodies are equipped with pre-primed doors, front and rear fenders, hoods, radiator trims, mud flaps, trunk lids and other parts to be painted along with the body.

Body assembly after painting is carried out in the reverse order of body disassembly.

III. Occupational safety and health

3.1 Basic provisions on occupational safety

Labor protection is understood as a system of legislative acts and corresponding measures aimed at preserving the health and performance of workers.

The system of organizational and technical measures and means to prevent industrial injuries is called safety precautions.

The system of organizational, hygienic and sanitary measures and means to prevent workers from becoming ill is called industrial sanitation.

The main provisions on labor protection are set out in the Labor Code (LC).

One of the main measures to ensure occupational safety is mandatory training for newly hired workers and periodic training for all employees of the enterprise. The briefing is conducted by the chief engineer. Newly hired employees are introduced to the basic provisions on labor protection, internal regulations, fire safety rules and features of the enterprise, the responsibilities of workers to comply with safety rules and industrial sanitation, traffic rules at the enterprise, protective equipment for workers and methods of providing first-aid to victims.

3.2 Requirements for technological processes

When maintaining and repairing vehicles, it is necessary to take measures against their independent movement. Maintenance and repair of vehicles with the engine running is prohibited (except for engine adjustments).

Lifting and transport equipment must be in good condition and used only for its intended purpose. Only persons who have undergone appropriate training and instruction are allowed to operate this equipment.

When disassembling and assembling components and assemblies, it is necessary to use special pullers and keys.

It is prohibited to block the passages between work stations with parts and assemblies, as well as to accumulate a large number of parts at disassembly sites.

The operations of removing and installing springs pose an increased risk, since significant energy is accumulated in them. These operations must be performed on stands or using devices that ensure safe operation.

Hydraulic and pneumatic devices must be equipped with safety and bypass valves. The working tool must be in good condition.

3.3 Requirements for work premises

The rooms in which the worker must be under the car must be equipped with inspection ditches, overpasses with guide safety flanges or lifts.

Supply and exhaust ventilation must ensure the removal of released vapors and gases and the supply of fresh air.

Workplaces must be provided with natural and artificial lighting sufficient for the safety of work.

The territory of the enterprise must be equipped with sanitary facilities: dressing rooms, showers, washbasins (with the mandatory availability of hot water when working with leaded gasoline).

IV. Conclusion

This course work examines the technological process of repairing passenger car bodies. Body malfunctions are examined in detail, as well as the process of defect detection of parts and methods for eliminating defects, and measures for labor protection and safety during repair work are considered.

V. Bibliography

1. “Car repair” S.I. Rumyantsev M. transport 1990-327 p.

2. Handbook of mechanical engineering technologist volume 2 M. mechanical engineering 1988-240 p.

3. Fundamentals of automotive technology and car repair M. mechanical engineering 1991-315 p.

4. E.S. Kuznetsov. Technical operation of vehicles. Moscow. Transport, 1991.

5. Occupational safety and health at motor transport enterprises Salov F.M. M.: 1991

6. F.N. Avdonkin “Current car repairs” M.: “Transport” 1988 p. 271

7. Construction, maintenance and repair of passenger cars. : textbook for beginners. professional education: S.K. Shestopalov.- M.: “Academy” 2006-566p.

8. “Car maintenance and repair” L.I. Epifanov. 2004

9. “Car repairman” A.S. Kuznetsov 2006

10. “Car maintenance and repair” V.M. Vlasov 2004

Maintenance involves strictly periodic cleaning, washing, refueling, lubrication, control and diagnostic, fastening and adjustment work. Maintenance work is divided into:

Guard duties - performed directly on a vehicle installed at a work station;

Precinct - performed outside the post (in auxiliary production areas);

Related routine repair work performed during maintenance (at or outside the posts).

On-site maintenance work is characterized by a very specific frequency, nomenclature and labor intensity.

Current repairs (as defined by GOST 18322--73) are repairs carried out during operation to ensure the operability of the vehicle and consist of replacing and restoring its individual parts and adjusting them.

TR work, according to the nature and place of execution, is also divided into stationary, workshop and related maintenance work performed at maintenance posts.

During technical repairs, they also perform coppersmithing, welding, tinsmithing, electrical engineering, tire repair, wallpaper, painting, fastening and adjustment work, the need for which arises between regular maintenance.

TR work is characterized by a large range of eliminated failures and malfunctions and significant fluctuations in the labor intensity of the work performed. The range of work performed during post repairs contains about 500 items, and the labor intensity of one (according to the nomenclature) post repairs ranges from 0.10-15.0 man-hours.

Typically, the need for technical repair work is identified at the request of the driver, at diagnostic or maintenance areas.

Development of a technological process for current repairs

Current repairs are intended to ensure the working condition of the rolling stock with the restoration or replacement of its individual units, components and parts (except for basic ones) that have reached the maximum permissible condition.

Routine repairs must ensure trouble-free operation of the repaired units, components and parts for a mileage of no less than until the next maintenance of TO-2.

Replacement of repaired units and assemblies and fastening and adjustment work are carried out in areas serving the cars and trailers assigned to them in accordance with the order.

Repair of units and components in ATP is carried out at the sites. The document that serves as the basis for placing rolling stock for current repairs is an application for repairs.

A repair request is issued when malfunctions are identified, mainly when rolling stock leaves the line, and in other cases with the permission of the deputy workshop manager for technical matters.

The control mechanic registers the repair request by serial number for each day in the repair request register and issues it to the driver. Informs the operation department about faulty vehicles and trailers in convoys.

The driver, having received the application, carries out cleaning and washing work on the rolling stock, presents the registration sheet to the site foreman and, with his consent, places the car for repair.

The driver directly involved in the repair, having written out a repair request, presents it to the convoy dispatcher. Based on the application, the dispatcher issues a registration sheet for the driver’s participation in ongoing repairs. After passing a medical examination and the corresponding mark on the driver’s participation record sheet for repairs, he presents it to the foreman of the section servicing the convoy.

While under repair, the driver is subordinate to the site foreman (performs work to repair the vehicle assigned to him or, by order of the head of the ATP, goes to the line with a serviceable vehicle in the absence of the driver of this vehicle).

At the end of the shift, the foreman fills out a record sheet for the driver’s participation in repairs, indicates the amount of work performed by the driver and, according to time standards, enters the number of hours worked per shift.

If there are no spare parts or a small amount of work on the assigned vehicle, the repairman has the right to transfer the driver to repair another vehicle in the same convoy. In this case, the driver is transferred to a part-time paid job.

Drivers hired for repairs are paid according to the tariff rate of repair workers.

The record sheet for the participation of drivers in repairs is the main document for payment to the driver, which, after registration by the site foreman, is handed over to the dispatcher daily.

After the repair is completed, the site foreman (foreman) writes down the name of the work performed in the appropriate section of the application and passes it on to the control mechanics.

Having received a record sheet with a mark on the completion of work, the control mechanic checks the technical condition of the cars when releasing them onto the line, after which he makes a mark for departure on the waybill, and if faults are detected, the car is sent back to the repair areas to eliminate the detected faults.

All applications are transferred daily, upon completion of vehicle production, by a mechanic from the control point to a repair engineer for processing and storage.

The work carried out on the lift in the maintenance and repair zone includes the following disassembly and assembly operations, repair operations without elements of restoring parts, i.e. replacement of faulty units, mechanisms and components of the vehicle with serviceable ones, replacement of faulty parts in them with new or repaired ones.

Routing

As an example, we give guard work on a lift to dismantle the rear axle during maintenance and repair of a KamAZ 5320 vehicle.

Table 4.1

Technological map for dismantling the rear axle of a KamAZ vehicle

operations	Name and composition of work (operations)	Location of operations	Number of units or parts	Profession and job category	Standard time	Specifications and instructions
	Place the car on a lift	Lift with lifting capacity 10t		Locksmith, 2
	Unscrew the filler and drain plugs			Locksmith, 2
	Remove the axle shafts			Locksmith, 3
	Unfasten and remove the hubs with brake drums and bearings			Locksmith, 3
	Unfasten the rear brakes, remove the tension springs, locking plates, pads, axles (eccentrics), supports, expansion knuckle brackets, wheel cylinders			Locksmith, 3
	Disconnect the rod forks from the levers, unfasten them, remove the pins, remove the brake chambers and brackets			Locksmith, 3
	Unfasten and remove the axle housing cover			Locksmith, 3
	Unfasten and remove the axle gearbox			Locksmith, 3
	Unfasten and remove the center differential lock mechanism			Locksmith, 3
	Unfasten, remove bearing caps and remove differential			Locksmith, 3

A technology for working on the designed lift has been developed and linked to the general system for carrying out maintenance and repair. A technological map has been drawn up for carrying out guard work on a lift to dismantle the rear axle during maintenance and repair of a KamAZ 5320 vehicle.

Federal Agency for Education of the Russian Federation

SYKTYVKA FOREST INSTITUTE

State educational institution

Higher professional education

"St. Petersburg State Forestry Academy

them. CM. Kirov"

Faculty of Forest Transport

Department of Automobiles and Automotive Industry

COURSE PROJECT

Discipline: Technical operation of vehicles

Subject: Organization of maintenance-1 of a KamAZ 53212 vehicle

KP. LTF. 190601.4 DO.061219. PZ

Completed by Skorobogatykh P.A.

Checked by Malashchuk P.A.

Head Department Chudov V.I. Ph.D.

Syktyvkar 2009

Introduction

Machine maintenance is a set of preventive measures during the overhaul period aimed at preventing failures in units and components and reducing the wear rate of parts. Maintenance includes inspection and diagnostic, fastening, lubrication, filling, adjustment, electrical and other types of work.

Car maintenance has the goal: to ensure the constant technical serviceability of units and components in the car as a whole; maximize turnaround time; guarantee traffic safety; ensure minimal consumption of operating materials.

To achieve these goals, our country has adopted a planned preventative maintenance system, which provides for the mandatory implementation of a set set of works at a given frequency during the use, storage and transportation of vehicles. The technological process of servicing a car with a planned preventative system provides for a combination of mandatory work with work performed on demand, the need for which is determined as a result of checking the condition of the car. Maintenance of special equipment installed on the vehicle is carried out, whenever possible, simultaneously with maintenance of the chassis.

Depending on the volume of work and the frequency of their implementation, maintenance is divided into the following types: control inspection, daily maintenance, maintenance No. 1 (TO-1), maintenance No. 2 (TO-2), seasonal maintenance (SO). The objective of this course project is to become familiar with the vehicle maintenance system, draw up a technological map, determine the number and placement of workers, and also select technological equipment. Draw a drawing of the car in two projections indicating the number and location of the maintenance operation. And a diagram of the technological layout of the post with the arrangement of equipment and workers.

Main technical characteristics of the KamAZ 53212 vehicle

Weight parameters and loads:

Vehicle curb weight, kg 8500

Car load capacity, kg 11000

Gross weight, kg 19650

Gross trailer weight, kg 14000

Gross weight of the road train, kg 33650

Installed engines:

Model 740.31-240 (Euro-2)

Type: diesel with turbocharging, with intercooling of charge air

Maximum net power, kW (hp) 165 (225)

Rated power, gross, kW (hp) 176 (240)

at crankshaft rotation speed, rpm. 2200

Max. useful torque, Nm (kgfm) 912 (93)

at crankshaft rotation speed, rpm 1100-1500

Arrangement and number of cylinders V-shaped, 8

Working volume, l. 0.85

Cylinder diameter and piston stroke, mm 120/120

Compression ratio 16.5

Supply system:

Fuel tank capacity, l. 500

Electrical equipment:

Voltage, V 24

Batteries, V/Ah 2×12/190

Generator, V/W 28/2000

Clutch:

Type friction, dry, double-disc

Hydraulic drive with pneumatic booster

Transmission:

Type mechanical, ten-speed

Mechanical control, remote

Gear ratios:

7,82 4,03 2,5 1,53 1,000 7,38

6,38 3,29 2,04 1,25 0,815 6,02

Main gear:

Gear ratio 5.43

Pneumatic drive

Dimensions: drum diameter, mm 400

Brake lining width, mm 140

Total area of ​​brake linings, cm2 6300

Wheels and tires:

Wheel type: disc

Rim size 7.5-20 (190-508)

Tire size 10.00 R20 (280 R508)

Over-engine type with high roof

Version with berth

Platform:

The platform is onboard, with metal folding sides, depending on the configuration, it is equipped with a frame and an awning

Internal dimensions, mm * 6100×2320 or 6114×2420 ("euro")

Side height, mm * 500 or 725 (“euro”)

Characteristics of a vehicle with a total weight of 19650 kg:

Maximum speed, no less, km/h 90

Climbing angle, not less, % 25

External overall turning radius, m 9.8

List of routine maintenance work for the KamAZ 53212 vehicle

Maintenance TO-1 for the KamAZ 53212 vehicle presented below is carried out in accordance with the “Regulations on routine repair and maintenance of rolling stock”. According to this provision, the first maintenance for trucks is carried out every 4000 km. These works include control and diagnostic, inspection, fastening and lubrication and cleaning work.

The list of works includes:

General inspection:

1. Inspect the car, checking the condition of the cabin, platform, glass, rear-view mirrors, tail, license plates.

2. Door mechanisms, platform side locks, towing (fly-wheel) devices.

3. Check the operation of the windshield wiper and washers, the operation of the heating system and glass heating (in the cold season), and the ventilation system.

Engine, including cooling systems, lubrication:

4. Inspect the tightness of the engine lubrication and cooling systems (including the starting heater).

5. Check by ear the operation of the valve mechanism.

6. Check the fastening of the exhaust tract parts (exhaust pipe, muffler, etc.) and the oil sump.

7. Check the engine mounting.

8. Check the condition and tension of the drive belts.

Clutch:

9. Check the free play of the clutch pedal. Check the tightness of the clutch release hydraulic drive system.

10. Check the fluid level in the compensation tank of the clutch release master cylinder.

Transmission:

11. Check the fastening of the gearbox and its external parts.

12. Check the operation of the gear shift mechanism with the vehicle stationary.

Cardan drive:

13. Check the fastening of the cardan shaft flanges. Check the play in the articulated and splined joints of the cardan transmission.

Rear axle:

14. Check the tightness of the rear (middle) axle connections.

15. Check the fastening of the gearbox housing and axle shaft flanges.

Steering and front axle:

16. Check the tightness of the power steering system.

17. Check the fastening of the nuts of the steering axles of the ball pins of the steering rods into the cotter pins.

18. Check the play of the steering wheel and steering rod joints.

Brake system:

19. Check the condition and tightness of pipelines and brake system devices.

20. Check the stroke of the brake chamber rods.

21. Change the alcohol in the freeze protector.

Chassis.

22. Inspect the condition of the frame, components and suspension parts.

23. Check the fastening of the stepladders and spring pins, and the fastening of the wheels.

24. Check the condition of the tires and the air pressure in them: remove foreign objects stuck in the tread and between the paired wheels.

Cabin, platform (body) and tail.

25. Check the condition and operation of the locking mechanism, stop-limiter and safety device for the tilting cab.

26. Check the fastening of the platform to the car frame,

27. Check fastenings, running boards, mudguards. Inspect the surfaces of the cabin and platform; If necessary, clean the corrosion areas and apply a protective coating.

Supply system.

28. Inspect the condition of the power system devices, their fastening and tightness of connections.

Electrical equipment.

29. Check the operation of the sound signal, instrument panel lamps, lighting and alarm, headlights, sidelights, rear lights, brake light and light switch.

30. Check the condition and fastening of electrical wires.

31. Check the mounting of the generator and the condition of its contact connections.

32. Clean the battery from dust, dirt and traces of electrolyte; clean the ventilation holes, check the fastening and reliability of contact of the wire tips with the output pins; check the electrolyte level.

Lubrication and cleaning work:

33. Lubricate the friction units and check the oil level in the crankcases of the units with a chemical map.

34. Clean the breathers of the gearbox and axles.

Checking the car after service:

35. After servicing, check the operation of the vehicle’s units, components and devices while driving or at a diagnostic station.

Technological map of KamAZ 53212 vehicle maintenance

Table 1

Technological map TO-1 of the KamAZ 53212 vehicle

No. of work performed	Title and content of work	Service location	Number of service locations	Devices, tools, devices, model, type	Technical requirements and instructions
General inspection
1	Inspect the car and check the condition of the cabin, platform, glass, rear-view mirrors, tail, paint, license plates and rear-view mirrors	Top, front, back	-	-	The glass of the cab, headlights, sidelights, and direction indicators must be intact. The platform boards must not have cracks or kinks. The condition of license plates must meet the requirements of the Road Traffic Regulations. Rear view mirrors must be intact and correctly adjusted
2	Check the serviceability of the cab door locks, platform side locks, and towing device	Above, behind	-		The mechanisms of doors and platform side locks must be in good working order. The towing device must be securely fastened to the frame and its hinged bracket must be pinned
3	Check the operation of the windshield wipers, the windshield washer and the windshield defogger and heating device (in winter)	In the cockpit	3	-	The windshield wiper blades must fit snugly along the entire length of the edge to the surface of the windshield and move without jamming or stopping. During operation, the brushes should not touch the seal. The glass washing device must be in good working order and wash the entire glass surface evenly
Engine, including cooling and lubrication systems
4	Inspect the condition and tightness of the cooling systems, engine lubrication, cabin heating system and starting heater	Up and down	4	-	Oil leakage at the mounting points of the oil filter and crankcase is not allowed. Leakage of coolant in the pipes and radiator is not allowed
5	If necessary, eliminate leaks in the pipelines of the cooling system, engine lubrication system, cabin heating system and starting heating	Same	4		Leakage of oil, coolant and fuel can be eliminated by tightening nuts, clamps or replacing individual parts.
6	Check by ear the operation of the valve mechanism	Above	1	-	Let the engine listen to its operation. There should be no knocking in the valve mechanism if it is adjusted correctly.
7	If necessary, adjust the gaps between the valves and rocker arms	Same	16	Device for adjusting valves I801.14.000 (10), set of probes No. 2 (15)	Thermal clearances in the gas distribution mechanism are adjusted on a cold engine no earlier than 30 minutes after stopping. In each position, simultaneously adjust the valve clearances of two cylinders in the operating order: 1-5-4-2-6-3-7-8, turning the crankshaft by 90 0 Thermal clearances are adjusted in the following order: set the piston of the first cylinder to i. m.t. of the compression stroke, rotate the crankshaft in the direction of rotation (counterclockwise, when viewed from the flywheel side) through an angle of 60 0 (rotating the flywheel by the angular distance between two adjacent holes corresponds to between two adjacent holes corresponding to turning the crankshaft by 30 0 ), At the same time, the valves of the 1st and 5th cylinders are closed (the valve rods can be easily turned by hand), check the tightening torque of the nuts securing the rocker arms of the adjustable cylinders and, if necessary, tighten them, to adjust the gap, loosen the adjusting screw nut, insert a feeler gauge into the gap and, turning the screw with a screwdriver, set the required gap. Hold the screw with a screwdriver, tighten the nut and check the gap. The gap should be 0.25-0.3mm for intake valves and 0.35-0.4mm for exhaust valves.
8	Check the fastening of the oil sump, exhaust pipes, muffler exhaust pipe flanges to the cylinder block and secure if necessary	Up and down	3	Auto mechanic set (large) I-148 (11), chisel (14), hammer (13).	Tighten the oil sump mounting nuts with a tightening torque of 1.5-1.7 kgf∙m, exhaust pipes 4.5-5.4 kgf∙m, exhaust pipe flanges of the muffler 4.5-5.4 kgf∙m
9	Check the mounting and, if necessary, secure the engine to the frame	Above	1	Auto mechanic kit (large) I-148 (11)	The nuts of the engine mounting bolts on the frame must be tightened and cottered. Carry out tightening with a tightening torque of 5.5 - 6 kgf∙m
10	Check the condition and tension of the generator and water pump drive belts	Above	1	Auto mechanic kit (large) I-148 (11)	The belt tension is ensured by moving the generator; a correctly tensioned belt, when pressing on the middle of the belt with a force of 4 kgf, the deflection should be 15-22 mm.
Clutch
11	Check the free play of the clutch pedal	In the cockpit	1	Ruler (16)	The pedal free play should be 6-12 mm
12	If necessary, adjust the free play of the clutch pedal	Same	1	Auto mechanic kit (large) I-148 (11)	The free play of the pedal is set by adjusting the gap between the piston and the master cylinder piston pusher. To adjust the gap between the piston and the master cylinder piston pusher, use the eccentric pin that connects the top eye of the pusher to the pedal lever. Rotate the eccentric pin so that the movement of the pedal from the top stop to the moment it touches the piston pusher is 6-12 mm, then tighten and cotter the castle nut.
13	Check the tightness of the hydraulic clutch release system	In the cabin and below	1	-	Liquid leakage in the main, working cylinder and pipeline is not allowed
14	If necessary, repair leaks in the clutch release piping	Same	1	Auto mechanic kit (large) I-148 (11)	Fluid leakage can be eliminated by tightening the nuts and replacing individual elements.
15	Check the fluid level in the compensation tank of the clutch master cylinder	Front	1	-
16	If necessary, add fluid to the compensation tank of the clutch master cylinder	Same	1	-	The liquid level in the tank from the top edge should be 15-20mm
Transmission
17	Check the fastening of the gearbox and its external parts	Up and down	-	Auto mechanic kit (large) I-148 (11)	Tighten the gearbox mounting bolts with a tightening torque of 5.5-6 kgf∙m
18	Check the operation of the gear shift mechanism with the vehicle stationary.	In the cockpit	1	-	Shifting gears must be done without jamming
Cardan transmission
19	Check the fastening and, if necessary, secure the flanges of the cardan shafts, check the play in the articulated and splined joints of the cardan transmission	From below	16	Auto mechanic kit (large) I-148 (11)	Play in hinged and splined joints is not allowed; flanges should be tightened with a tightening torque of 12.5-14 kgf∙m
Rear (middle) axle
20	Check the tightness of the connections of the rear (middle) axle, if necessary, eliminate the leak	From below	2	Auto mechanic kit (large) I-148 (11)	Oil leakage is not allowed. Eliminate leakage by tightening the nuts or replacing individual elements of the unit; tighten with a tightening torque of 1.5-1.7 kgf∙m
21	Check the fastening and, if necessary, tighten the fastening nuts of the gearbox housing and axle shaft flanges	Below and above	-	Auto mechanic kit (large) I-148 (11)	Tighten the gearbox mounting nuts with a tightening torque of 16-18 kgf∙m
Steering and front axle
22	Check the power steering system for leaks	Above	-	-	Oil leakage in the oil line and in the pump is not allowed
23	If necessary, repair the leakage of the power steering system	Same	-	Auto mechanic kit (large) I-148 (11)	Oil leakage can be eliminated by tightening the nuts and replacing individual elements.
24	Check the fastening and cotter pins of the steering axle arm nuts. Troubleshoot if necessary	From below	3	Auto mechanic set (large) I-148 (11), pliers (12)	The nuts securing the steering axle arms must be tightened and cottered. Tighten the levers with a tightening torque of 36-40 kgf∙m. The levers should not have play in the socket and on the key.
25	Check the fastening and cotter pins of the ball pin nuts of the longitudinal and transverse steering rods. Troubleshoot if necessary	Same	3	Auto mechanic set (large) I-148 (11), pliers (12)	The ball pin nuts must be tightened and cottered. Backlash of fingers in conical sockets is not allowed. tighten the ball pins with a tightening torque of 9-10 kgf∙m
26	Check steering wheel play	In the cockpit	1	Device model NIIAT K-402 (8)	The check is carried out on a loaded car (without load) with the engine running at a speed of 600 - 1200 min -1, with normal tire pressure, the front wheels set straight, the free play of the wheels on a new car should not exceed 15 0. Maximum permissible free play 20 0
27	Check the play in the steering rod joints	Below and in the cockpit	3	-	Play in the steering rod joints must be checked by the relative movement of the ball pins and rod ends or heads when the steering wheel is sharply turned in both directions. Play in steering rod joints is not allowed.
Brake system
28	Check the serviceability of the brake system using an external inspection and according to the readings of standard instruments.	Below and in the cockpit	-	-	The pressure created by the compressor should be 6.2-7.5 kgf/cm2. When you press the brake pedal, the pressure should drop sharply by no more than 0.5 kgf/cm2
29	Check the condition and tightness of the brake system pipelines and devices and, if necessary, correct the malfunction	Up and down	-	Auto mechanic kit (large) I-148 (11)	Depressurization of the brake system is not acceptable. Depressurization can be eliminated by tightening the nuts or replacing individual elements of the system
30	Check and, if necessary, adjust the stroke of the brake chamber rods	From below	6	Auto mechanic set (large) I-148 (11), pliers (12), ruler (16)	The stroke of the rods should be no more than 40mm. Carry out the check in the following order: install a ruler parallel to the rod, resting its end against the brake chamber body, mark the location of the extreme point. Press the brake pedal all the way (pressure in the pneumatic drive is at least 6.2 kgf/cm2, the drums are cold, the parking brake system is turned off), mark the location of the same point. The difference between the obtained values ​​is the stroke value of the rod. The stroke of the rod is adjusted by turning the worm axis of the adjusting lever, after unscrewing the lock two or three turns. Rotate the axis to set the smallest stroke
31	Change the alcohol in the freeze protector	Above	1	Auto mechanic kit (large) I-148 (11)	Drain sediment from the filter housing. To fill alcohol and control its level, release the rod handle to the lower position and fix it by turning it 90 0, unscrew the plug with the level indicator, pour alcohol and close the filling hole, turn on the fuse
Chassis
32	Inspect the condition of the frame, components and suspension parts	From below	-	-	There should be no loosening of rivet joints, cracks, spars or cross members.
33	Check the fastening of the spring ladders	Above	-	Auto mechanic set (large) I-148 (11), wrench for nuts of stepladder springs model I-314 (7)	tighten stepladders with a tightening torque of the front ones - 25-30 kgf∙m, back 95-105 kgf∙m
34	Check wheel fastening	Same	30	Impact wrench for wheel nuts model I-303M (6) or wheel wrench 535M (9)	Tighten the nuts with a torque of 25 - 30 kgf∙m evenly, in one or two or three steps, starting from the top.
35	Check the condition of the tires and the air pressure in them, remove foreign objects stuck in the tread and between the paired wheels	Same	10	Air dispensing column model TsKB S-401 (1) or tip with pressure gauge model 458 (2), pliers (12)	The tire should not have cracks, tears, or swelling. The tire valve must have a cap. Air pressure 5.3-7.3 kgf/cm2. The remaining tread depth in the center of the treadmill must be at least 1.0 mm
Cabin and platform
36	Check the condition and operation of the locking mechanism, stop-limiter and safety device	Above	-	-	The locking mechanism and safety devices must be in good condition
37	Check the fastening of the platform to the vehicle frame and secure if necessary	Same	-	Auto mechanic kit (large) I-148 (11)	tighten the platform fastening nuts with a tightening torque of 18-21 kgf∙m
38	Check the fastening of the footrests and mudguards, secure if necessary	Same	-	Auto mechanic kit (large) I-148 (11)	Tighten the footrests with a tightening torque of 1.5-2.5 kgf∙m, mudguards with a tightening torque of 1-2 kgf∙m
39	Inspect the surface of the cabin and platform, if necessary, clean areas of corrosion and apply a protective coating	Top, front, back	-	Wire brush	Rust, paint peeling, cracks are not allowed
Supply system
40	Inspect the condition and tightness of the power system: low pressure fuel pump, fine fuel filter, fuel tank, fuel sediment filter, fuel line connections, high pressure fuel pump and fine filter	Above	-	-	Fuel leakage in the instruments and fuel lines of the system is not allowed. Fuel lines must not be bent or cracked
41	If necessary, eliminate leaks in devices and connections of fuel lines of the power supply system	Same	-	Auto mechanic set (large) I-148 (11), pliers (12)	Fuel leakage from instruments and fuel system connections is eliminated by tightening individual connection elements. tighten with a tightening torque of 4.5-5.4 kgf∙m
Electrical equipment
42	Check the operation of the horn, headlights, sidelights, rear light, brake light, instrument panel lamps and direction indicators	In the cabin and above, front, rear	-	-	All lamps should produce light without blinking, and the sound signal should be sharp without rattling or wheezing.
43	If necessary, replace faulty headlight, sidelight and rear light bulbs	In the front and in the back	-	Auto mechanic kit (large) I-148 (11) sanding paper (19)	When replacing lamps, it is necessary to clean the contacts of the sockets.
44	Check the condition and fastening of electrical wires	In the cabin, front, top, rear	-	Auto mechanic set (large) I-148 (11), pliers (12)	Electrical wires must be in good condition and securely fastened
45	If necessary, insulate damaged areas of electrical wires (up to 200 mm long)	Same	-	Pliers (12), mounting knife, insulating tape	Damaged areas of electrical wires must be carefully insulated
46	Check and, if necessary, secure the generator	Above	1	Auto mechanic kit (large) I-148 (12)	-
47	Clean the surface of the battery from dust, dirt and electrolyte.	Above	1	Rubber gloves (17), rags (20), bath with a solution of ammonia or soda ash, brush (18)	The surface of the battery must be dry and clean. The electrolyte must be wiped with a rag soaked in a solution of ammonia or soda ash.
48	Clean the ventilation holes in the battery plugs	Same	6	Battery plug wrench (17), wooden stick Æ 1.5 mm, rags (20), rubber gloves (17)	-
49	Check the electrolyte level in the battery and, if necessary, add distilled water	Same	6	Level measuring tube (17), rubber gloves (17), rubber bulb (17)	The electrolyte level in the cells should be 10-15mm above the top edge of the safety grid
50	Check the fastening and condition of the wire tips with the battery terminals	Same	2	Auto mechanic kit (large) I-148 (11)	The terminals of the lugs must make good electrical contact
51	If necessary, clean and lubricate the battery terminals and wire ends	Same	2	Rags (20), sanding paper (19)	Clean oxidized battery terminals and wire ends and apply non-contact surfaces with Litol 24 lubricant GOST 21150-87
Lubrication and cleaning work
52	Check the oil level in the engine crankcase	Above	1	Oil dipstick and rag (20)	Check the oil level with the engine not running in the following order: remove and wipe the dipstick, insert it into the socket until it stops and remove it. The oil level should reach the upper mark
53	If necessary, add oil in the crankcase to normal levels.	Same	1	Oil dispenser model 367МЗ (4), rags (20)	When using oil M-10G 2 k, GOST 8581-78, in winter - M-8G 2 k, GOST 8581-78, all-season - DV-ASp-10V
54	Check the oil level in the power steering pump reservoir	Same	1	-	The oil level should be between the marks on the indicator.
55	If necessary, add oil in the power steering reservoir to the correct level.	Same	1	Rags (20)	Add oil to the specified level with the engine running at minimum crankshaft speed. Oil for the hydraulic system of a car, grade "R".
56	Check the oil level in the gearbox housing	From below	1	Auto mechanic kit (large) I-148 (11), rags (20)	Unscrew and wipe the oil dipstick, insert it into the socket until it stops and remove it. The oil level should reach the upper mark
57	If necessary, top up the gearbox housing to the correct level.	Same	1	Auto mechanic kit (large) I-148 (20), installation for filling car units with transmission oil model 3161 (3)	TSp-15k, GOST 23652 - 79 (at temperatures not lower than minus 30 0 C), TM5-12RK, TU38.101.844 - 80 (at temperatures up to minus 50 0 C).
58	Check the oil level in the rear (middle) axle housing	Same	2	Auto mechanic kit (large) I-148 (11)	The oil in the rear axle housing should be at the level of the inspection hole
59	If necessary, add oil to the rear (middle) axle housing to the correct level.	Same	2	Auto mechanic kit (large) I-148 (11), installation for filling car units with gear oil 3161 (3)	TSp-15k, GOST 23652 - 79 (at temperatures not lower than minus 30 0 C), TN5-12RK, TU38.101.844 - 80 (at temperatures up to minus 50 0 C).
60	Clean the breathers of the gearbox and rear (middle) axle	Below and above	3	Rags (20), wire with a diameter of 1.5 mm	-
61	Lubricate the front axle steering knuckle pins	From below	4	Solidolon blower model 390 (5)	Lubricant Litol - 24, GOST 21150 - 87. Substitutes: solid oil Zh, GOST 1033 - 79 or solid oil S, GOST 4366 - 76, Lubricate through grease nipples until fresh grease is squeezed out
62	Lubricate the front spring pins	Front	2	Same	Same
63	Steering rod joints	From below	4	Same	Same
64	Lubricate the brake adjustment levers	Same	6	Same	Same
65	Expansion fist shaft bushings	Same	6	Same	Lubricant Litol - 24, GOST 21150 - 87. Substitutes: solid oil Zh, GOST 1033 - 79 or solid oil S, GOST 4366 - 76. Lubricate through grease fittings, making no more than five strokes with a syringe
Organizational work. Preparation of documents and quality control of vehicle maintenance
66	Place the vehicle at the service station.	Fast	-	-	The vehicle must be installed at the work station only after labor-intensive repairs, cleaning and washing work, and in a clean and dry condition.
67	Enter data on the completion of TO1 into the vehicle maintenance and current repair record sheet.	office desk	-	-	-
68	Provide assistance and monitor the quality of performers’ work.	-	-	The operation is performed by a master or senior mechanic.

Map of the arrangement of performers at the maintenance station

Table 2. Map of the arrangement of performers at the maintenance station

Purpose of the post	The serial number of the performer and his qualifications	Location of execution	Number of works and sequence of their execution	Notes
Inspection work, engine maintenance, electrical equipment, gearbox, switchgear, clutch, lubrication work.	No. 1, Car repair mechanic, 3rd category	Top, front, rear, cab	3, 11, 12, 13, 14, 18, 26, 27, 28, 30, 42, 44, 45, 1-5,10, 22, 23, 6, 7, 36, 38, 39, 8, 9, 17, 21, 33, 34, 35, 40, 41, 43, 46-55, 15, 16	Operation 42 is performed by the 1st and 3rd performers jointly.
Lubrication, cleaning, refueling work, maintenance work on the chassis, transmission, cardan shafts and control gear	No. 2, Car repairman, 2nd category	From below	13, 14, 27-30, 4, 5, 8, 17, 19, 20, 21, 24, 25, 32, 56-61, 63-65	Operations 27 and 30 Performed by the 1st and 2nd performer jointly
Organizational work, paperwork and quality control of service.	No. 3 Car repairman, 4th category (foreman)	Above	64, 65, 66	The tasks of the foreman include paperwork, quality control and assistance in difficult situations.

Table of main and additional equipment

Table 3. Table of main and additional equipment

No.	Name of equipment	Model, type, GOST	Brief technical information	Manufacturer
1	Automatic air dispenser	TsKB S-401	Stationary, automatic; air supply pressure 5..8 kgf/cm2; measurement limits on a scale from 1.5 to 6.5 kgf/cm 2, scale division price 0.1 kg/cm 2	Bezhetsk Automotive Equipment Plant
2	End piece with pressure gauge for air distribution hose	458	Manual, universal; pressure measurement limit 6 kg/cm 2 ; pressure gauge scale division price is 0.2 kg/cm 2.	Same
3	Gear oil filling installation	3161	Stationary, submersible, with automatic operation; productivity through two hoses is at least 12 l/min	Cherepovets Automotive Special Equipment Plant "Red Star"
4	Oil dispenser with pumping unit	376M3	Stationary, submersible with automatic operation; productivity 8-12 l/min	Same
5	Mobile solid oil blower with electric drive and hopper	390	Mobile, with electric drive; maximum developed pressure 400 kg/cm 2 ; productivity 150 g/min; useful hopper capacity	Kochubeevsky plant "Automotive special equipment"
6	Impact wrench for truck and bus wheel nuts	I-303M	Mobile, electromechanical, inertial-impact action; nut tightening torque at the first load position 50-60 kgf∙m	Gremyachinsky plant "Autospecial equipment"
7	Impact wrench for spring ladder nuts (ditch)	I-314	Maximum torque 82 kgf∙m	Chita plant "Autospecial equipment"
8	Universal device for checking car steering control	NIIAT K-402	Manual, mechanical, universal; measurement range; on the backlash meter scale 25 - 0 - 25 o, on the dynamometer scale up to 2 kgf
9	Wheel wrench	535M	-	Kazan SEZ "Automotive special equipment"
10	Engine valve adjustment tool	I801.06.000	Tubular wrench combined with a screwdriver	-
11	Auto mechanic kit (large)	I-148	Contains 44 items. Key sizes, mm - from 7 to 32	Kazan SEZ "Automotive special equipment"
12	Combination pliers	Pliers 7814.0161 1Х9 GOST 17438 - 72	-	-
13	Metalsmith's steel hammer	Hammer 7850-0053 Ts 12ХР GOST 2310-70	Nominal weight 500g	-
14	Cold chisel	Chisel 2810-0189 GOST 7211-72		-
15	Set of probes No. 2	Probes No. 2 GOST 882-75	The thickness of the probe plates is 0.02-0.10; 0.15-0.50mm	-
16	Measuring metal ruler	Line 1-150	-	-
17	Set of devices and tools for battery maintenance	E-401	Portable, consists of 15 items	Novgorod SEZ "Automotive special equipment"
18	Hair brush	GOST 10597-70	-	-
19	Sanding paper	GOST 6456-75	-	-
20	Wiping cloth	GOST 5354-74	-	-
21	Mechanic's workbench	ORG-1468-01-060A	-	Own production
22	Chest for cleaning materials	OG.03-000	-	Same
23	Waste chest	OG.16-000	-	Same

Conclusion

In the course of the work carried out, a scheme for carrying out maintenance at one station for the KamAZ 53212 vehicle was developed. A list of operations performed during the first maintenance was determined, which includes 35 points. During maintenance, fastening, filling, adjustment, and inspection work is performed. A diagram of the arrangement of performers has been drawn up. A list of main and additional equipment has been compiled. The graphic part of the course project has been completed. The first part of which is a drawing of the car in two projections indicating the number and location of the maintenance operation. The second part is a diagram of the technological layout of the post with the arrangement of equipment and workers

Bibliography

1. Technology for performing routine maintenance of the first and second maintenance of the GAZ 53A car.

2. Central design and technology bureau for the implementation of new technology and scientific research in road transport (CENTRAVTOTECH). - M. Transport, 1978. - 136 p.

3. Regulations on the maintenance and repair of rolling stock of road transport Approved on September 20, 1984. M.: Transport 1986, 73 p.

4. Practical guide to the maintenance and repair of KamAZ P69 vehicles, type 6X4/ E.A. Mashkov. - M.: Mechanical Engineering, 1994. - 243 pp.: ill.

5. Sheet of garage and technological equipment for motor transport enterprises of different capacities. S.A. Nevsky. - M.: Publishing house. CENTRTRUDAVTOTRANS, 2000. - 93 p.