Heading work "Reverser repair"

Operating conditions of the unit on the locomotive, characteristic damages and causes of their occurrence

Electric vehicles of electric rolling stock are subjected to different forces in terms of their values ​ ​ both from the side of the rail track (shocks, shocks) and from the side of electric impact - voltage and current, the values ​ ​ of which can change sharply several times during one trip. An important value is played by temperature modes, which vary within the range of more than ± 40 ° C. In addition, the technical condition of the devices and their location on electric locomotives and MVPS have a significant impact on quality work. So, devices located on the roof or under the body are more exposed to the environment. They accumulate more dirt, dust and moisture, but compared to devices located in the body. The working conditions of electrical devices in various circuits are very difficult, therefore, increased attention is required when performing all types of maintenance and repairs.

As a result of frequent disconnections and actuations of the devices in their nodes, additional heating, melting, heating occur. workings in hinged joints and the like. In addition, contact surfaces may be disturbed, insulation is broken, cross-section is reduced or connecting wires and flexible shunts are broken. In devices with pneumatic drives, in addition to the above failures, increased wear in the parts of electro-pneumatic valves, wear of pistons, cylinders, crack formation and the occurrence of air leaks in various places of connections and seals are possible.

Violation of the technology of manufacturing parts, assembly and testing of electrical devices also leads to their premature wear and possible malfunctions of the equipment of the electric locomotive or MVPS.

At the same time, electrical devices must provide clear, reliable and trouble-free operation with a minimum air pressure in the pneumatic line (up to 0.35 MPa) and a minimum voltage in the control circuits (test voltage up to 30 V). In addition, the devices (or their brackets, boxes) must have a reliable attachment to the body, protection against penetration of dust, moisture and dirt, as well as sufficient insulation resistance.

The main reason for the deterioration of the state of contacts is a decrease in their pressing. It occurs not only in case of incorrect adjustment of the device, jamming of its movable system, but also in case of damage or violation of adjustment of the lapping, switching on or off springs. The spring can also lose its elastic properties due to excessive heating during loosening of the attachment or breaking of the shunt of its copper shunt, transfer of the electric arc or unacceptable heating of the apparatus contacts. The consequences of reducing the contact pressure are significantly aggravated if under the action of body vibration there is a change in the pressing ("raking") of the contacts of the switched on device.

Another reason for excessive heating may be the improper mating of the contact surfaces, which results in the metal burnout at the point of their touch and the formation of a spot with a rough surface. In the future, these burns cause darkening of the entire contact and its melting.

Group switches of domestic electric locomotives, as a rule, are repaired on the spot. To determine the degree of serviceability of the device and identify hidden defects, it is useful to start the repair of the device by checking the scan of the main and auxiliary drums. At the same time, it is easy to detect the weakened or worn out cams of the shaft, the incorrect location of the disconnecting rollers and other defects and outline ways to eliminate them. If necessary, remove individual faulty units, damaged contact element, pneumatic drive with cracks or clamps on the working surface of the cylinder, faulty locking contacts and other parts.

Most of the failures of group-driven devices are caused mainly by the natural wear of their individual parts. The reverser of PK022T has following main malfunctions: wear of cam washers, contacts, hinged joints, loosening of contactor elements attachment, wear of cylinder working surfaces and collars of pneumatic actuators pistons, jamming or jamming of cam shaft, fracture of sector teeth, wear and skew of gear train, faults in the arc extinguishing system, air leakage in the pneumatic drive, excessive heating and breaking of the cores of the shunts, fracture of locking fingers, mechanical or electrical damages of insulation, breakaways and cracks in insulators, cracks in the frames of the devices and, as a result, a violation of the correctness of the switching made by the device .

Methods of cleaning, inspection and monitoring of technical condition

Before installation of EPS at the position of technical inspection or repair, it is blown with compressed air, and in accessible places it is cleaned from contamination with napkins. In order to ensure the inspection of all equipment and units of electric devices, as well as the cleaning of the cooling air ventilation system, the roof of the body is removed from the electric rolling stock in the depot shops, special side hatches and covers of body equipment boxes are opened.

The condition of electric locomotives and MVPS devices is first determined by the conclusion of diagnostic devices. Then external inspection is performed to detect possible malfunctions of devices. The following is checked:

reliability of attachment ;

make sure that there are no jams in the hinged connections, air leaks in the pneumatic drives;

monitor the operation of contacts, mechanical interlocks, as well as the state of arc extinguishing devices, insulation of wires and cables;

pressure of contacts of their solutions and dips is measured .

After visual inspection, detected defects are recorded in the repair log, compared with the conclusion obtained by diagnostic devices, and conclusions are made about the need for repair. According to the rules of repair during technical inspections and repairs, most of the devices are repaired directly on the locomotive, if their disassembly is not required.

The contactor elements of the reversers are less susceptible to wear, since they switch less often than the contactor elements, and the switches themselves occur when the circuit is de-energized, so they do not have arc extinguishing systems.

During repair, reversers inspect the condition of the main contacts and check their attachment. Contacts are cleaned from coke and strains with grinding skin. Strongly melted contacts are sawn with a small (personal) filler, after which the solution, transverse mixing and thickness of the contacts are measured. The solution of the main contacts must be at least 17 mm. and the greatest transverse displacement relative to each other is not more than 2 mm, The thickness of the main movable contact is allowed to be not less than 7 mm, and the fixed one is allowed to be not less than 2.5 mm.

The amount of contact pressing is determined in the same way as for individual contactors using a dynamometer. After the device is switched on, the dynamometer is pulled by the right hand and simultaneously by the left hand by a strip of paper previously clamped between the contacts. Readings are taken at the moment when the strip can be dragged without damaging it. Final pressing of power contacts for a reverser of PK022T makes 12.6 kgfs.

Segments of locking contacts having thickness less than 2 mm are replaced. Wear of cam washers is allowed within the limits, at which correctness of reverser sweep and pressure and contact rupture corresponding to technical data are maintained.

After checking reliability of attachment of all parts, condition of contact surfaces, pressing and wear of locking contacts are determined. In case of cracks in locking pins or their wear to thickness 0.54 mm

the fingers are replaced. Pressing of locking fingers is set equal to 1.0-2.5 kgf. In the fixed position of the interlocks, the fingers must fit on the segment or have a break with it of at least 2 mm.

Technology of repair (replacement, restoration, way of restoration) and increase in reliability

Clean the frame of old paint with a shaver and a metal brush. Brew the detected cracks by electric welding and grind. After welding, the surface must lie in the same plane.

Non-parallelism is allowed not more than 2 mm. Run threads in holes with throttle M10. Measure the dimensions between the mounting holes. They should not exceed 1mm from the drawings. If the size of the hole deviates, brew by electric welding and drill new ones. After survey (repair) of a framework paint gray GF92HS enamel.

After disassembly of the part, the contact elements of the reversers are cleaned. Power contacts, shunts, springs, bearings are inspected.

The thickness of the main movable contact should be 8-12.5 mm, and the maximum wear of the main fixed contact should be no more than 3.5 mm.

Cracks in levers are brewed, treated and then plated. Getinax bars (posts), with minor meltdowns, are cleaned with sandpaper or personal file and polished. Struts with deep runs, delamination, cracks and significant mechanical work at the attachment points of the brackets are replaced. Remote spacers of metal cheeks are riveted and welded by arc welding.

Contact elements of reversors are disassembled, rubbed, varnish is cleaned with scrapers from Getinax finger holder.

A finger holder with cracks, delaminations or significant burns is replaced. The finger crumbs are cleaned with glass paper, the places of their melting - with a personal file, and when worn over a height of more than 1 mm, they are replaced. The defective crumb is removed, the new one is riveted to the spring and soldered with POS40 solder. Spring pins, nuts, screws, bolts, installation plates and liners with damaged thread, with broken splined slots or faces, which have lost their elasticity, are replaced, and suitable ones are galvanized.

Cast reverser segments shall be not less than 3 mm. Segments with increased wear, mechanical damage or melted ones are restored by gas surfacing. Defective fiber segments are replaced with new ones impregnated in linseed oil. Final finishing of working surfaces of segments (their grinding) is performed on assembled drum on lathe. The oncoming edges of the segments round.

Locking devices are inspected. Plate contacts with output of more than 0.55 mm, with cracks, burns or those that have lost elasticity are replaced. Wear of movable contacts (segments) shall not exceed 1 mm at their nominal thickness of 3 mm and 2 mm at thickness of 5 mm.

Insulating blocks of holders of fixed and movable contacts of cam-type switches and fixed contacts of drum-type switches are washed with gasoline and inspected. Blocks with cracks, burns, fuses and with loosening of threaded bushings pressed into them are replaced. Minor damage is cleaned with glass paper and ground.

The developed holes in the rod and the bar at the points of their hinge joint are welded and drilled under the drawing size. Roller with wear more than permissible is replaced.

Cam element

During inspection of Getinax slats, their surfaces must be painted with electrically insulating enamel, and have no cracks, dents, bulged. If there are cracks and breakdowns, drill the split parts of the struts, disassemble the straps and replace the unsuitable parts. Clips along edges measuring 15x15 to a depth of 5 mm are allowed. To smooth out the damaged sites of a covering an emery paper and to enamel GF92HS red.

Weld cracks on contact and hinge struts and treat them with a filler. Run thread in holes with thrower M8. The diameters of the hole in the hinge post are checked. Hole diameter must not exceed -

seam 12.5 mm. Drill the developed holes with a drill by 12.5 mm and with further setting of the new roller to 0 12.5. Galvanize the contact posts.

Movable contacts having a thickness of less than 10 mm are replaced by new ones. Measure the length of the fixed contacts and check the soldering quality at the bus connection with the contact. If the connection loosens, rivet it, if it is impossible, drill it with drill 0 8, install a new one and perform soldering with solder of POSS 302.

Fixed contacts with thickness less than 43mm are replaced by new ones, developed and melted places are treated with a file. After replacement or repair, they are tin 9MK. Shunts with a wire break of more than 5% "180 + 230 pieces are replaced.

During inspection of the lever, detected traces of corrosion, cracks and dents with a depth of more than 3 mm, an area of ​ ​ more than 1 mm and a number of more than 4 pieces on the cheeks are disassembled. The lever cheeks are bent by setting the ruler cheek on the plane. The clearance between the ruler and the cheek plane is measured using a set of probes No. 4, it must be no more than 2 mm. If the clearance is more than 2 mm, if possible, the cheeks are brushed without disassembly, the same cheeks with dents up to 3 mm deep and an area up to 1 cm2 are brushed without disassembling the lever. If impossible, the lever is disassembled, the cheeks are flashed with a depth of more than 3 mm and an area of ​ ​ more than 1 cm2 using a hammer.

Measure the height of the collar and the diameter of the spliced part of the rivet. Collar height must be not less than 0.7mm, diameter not less than 10mm. In case of cracks on bushings, weakening of rivet joint, mismatch of collar dimensions and diameter of riveted part with technical requirements, rivets are drilled by drill and knocked out. The ends of the new rivets unfold and

the height of the collar and the diameter of the rivet are measured again, then the ends are painted with gray enamel GF92XS. During flattening of rivets on the press it is necessary to be guided by the specified safety measures according to the press certificate and ins-

Safety System for Press Operation.

We inspect and measure the spike, at a height of less than 4 mm it is drilled and replaced. The new one is installed in a heated state, after splitting in hot form, lower it into water.

Check the characteristics of the springs according to the drawings in cases of non-compliance with the drawing data, replace. Galvanize suitable springs. It is permitted to restore the steel springs with subsequent heat treatment.

Cam shaft

When repairing the cam shaft, first of all, its thread is inspected. The detected torn thread must be welded and cut again. Diameter of shaft necks for bearings is checked. In case of deviation from dimensions, wear and balls, necks are built up and processed on lathe.

At least 7.2 mm in case of cracks, brew and treat the ring. If dimensions do not correspond, replace it, refer to JI ( process.

Wash the bearings in kerosene, blow them with compressed air and wipe them with napkin. Check them for ease of rotation, paying attention to jamming and braking. In case of abnormal rotation of bearing rinse again with repeated check. Bearings with mechanical damages of parts (chips, cracks, fractures, radial run-out, and burrs on separators), corrosion on raceways, overheating traces shall be replaced. Strict control is also carried out on cam washers. Camshafts with cracks and wear of working surface of more than 2 mm are replaced by new ones. The failure of the keyway when its dimensions deviate from the drawing sizes of more than 8 + 0,013 mm is welded by electric welding and processed on a milling machine.

Blocking. Inspect the locking frame. Measure thickness of strips of car-

helmet, which must be not less than 9.2mm, if thickness does not correspond, replace the strips according to the technical process .

Cut the detected cracks and process. The thickness of the bar at the thrust is also measured, if the size of the bar is less than 7.2mm, it must be replaced, the cracks are brewed and processed.

Inspect and measure the roller diameter at the place of installation on the frame, diameter is not less than 19mm. The thickness of the plate installed on this roller is not less than 7.2mm, in case of non-conformity, replace. Roller necks having wear, as well as crumpled ends are restored by welding and subsequent treatment. Examine the contact pins and plates and replace the plates with thickness less than 2.5 mm if the thickness of the fingers in the working part is less than 1 mm and with cracks.

Finger holders and contact holders having balls and nicks must be cleaned and polished.

Drum

Clean all drum parts from dirt and inspect. If there are burns and cracks, replace the bakelite cylinder. Grind small surface heats of the cylinder with a depth of up to 1 mm with emery paper on a fabric basis.

If the thickness of the plate power and locking segments is less than 4 mm, the segments are replaced. The thickness of the insulation segments shall be less than the thickness of the contact segments by 1.5K2 mm. When replacing segments of an opening in a drum under screws for fastening of segments to close up wooden traffic jams on GF92HS enamel. When replacing all segments on the cylinder, the initial marking line must be shifted so that the screws do not fall into the previous holes. Holes for screws are drilled by drill 0 2.5 to depth of 15 mm. To paint a drum GF92HS enamel gray.

Pneumatic drive. Replace the cylinder with cracks, including welded ones. The internal diameter of the cylinder is more than 100.4mm. A rack with cracks and tooth fracture, as well as with a tooth thickness of less than 6 mm at a height of 4 mm, is replaced. Gears with teeth cracks and teeth thickness less than 6 mm at height of 4.12 mm are replaced.

If the length of the stop is less than the drawing dimensions, build up and process.

Galvanize the air distributor tubes and replace the tubes with cracks and dents.

Lubricate the drive cylinder with rubber cuffs with ZhT79L TU 02540020105595404 lubricant with ZhTKZ65 TU 32CT 546-78 lubricant, in the amount of 120 grams per drive.

Air drive is painted with grey PF115 enamel from outside.

Reverser Assembly

After replacement and repair of parts assemble the lever by connecting the lever jaws with the insert. Galvanize the lever, then install rivets, bushings and bearings between the cheeks. Spread rivets, controlling the size of the collar and diameter.

Assemble levers with movable contacts. Take turns to put contact posts on the bar. Put on brackets and attach them with bolts. After assembly, the contact line must be at least 80% of the width of the contacts, and the displacement of the contacts relative to each other must be at most 1.5 mm. Bearings are lubricated by TSIATIM201, only those that do not have protective washers.

Camshaft assembly after repair:

Press the assembled ring on the shaft.

Insert Pin and Splice.

Put cam washers on the shaft in sequence, according to the drawing, install electrical cardboard gaskets between them and attach them with a nut. Gaskets are installed only if necessary to eliminate hanging of the roller from the cam washer.

After the lock is repaired, it must be assembled. To combine openings of the holder and to fix them by the M5X12 screw. To establish blocking fingers, on the place, having combined their openings with openings a finger of holders and to fix them by M5x12 screws.

Insert the roller into the framing hole. Insert cotter pins into the roller holes and bend them. To combine openings of paltsederzhatel with openings of the roller and to fix them by screws M 6x12. Align the tie rod hole with the roller hole. Insert the rod on the roller. We fix, install the push-pull rod, and bend the cotter pin into its hole.

After inspection and repair, we collect, first we insert the assembled shaft into the holes of the frame. Then press the assembled bearing bodies on each side into the frame holes and attach them with bolts.

Installation of the gear on the shaft. After the key is installed in the key groove of the shaft, press the gear (pos. 1 and attach it with nut M24 with installation of spring washer.

Assembly and installation of pneumatic drive. To enter an emphasis in a cylinder and to fix by its two bolts M10x25 with statement of spring washers. After installation of stop lubricate its surface with ZhT79L lubricant TU0254-002-01055954-01. On the rack, install pistons and washers. Put new cuffs on pistons with a period of no more than two years from the day of manufacture. Attach pistons and washers on opposite ends of rack by nuts M6 with installation of spring washer. The pistons shall not extend outside the cylinder. Apply gaskets at cylinder ends to eliminate air leaks during operation. Then it is necessary to combine four openings of covers with openings of flanges on faces of a cylinder and to fix by M10x30 bolts. To attach the pneumatic drive to the frame, align four holes of cylinder attachment with holes of the frame and attach with M12 * 30 bolts with installation of spring washers.

Align four junction box holes with valves, with

framework openings to insert tubes guides, to fix by M10x80 bolts imposing of new paronitovy laying. Screw the nipples into the cylinder and into

junction box, connect junction box and cylinder with tubes. When assembling, extend the ends of the new tubes to 0 12mm at a length of 10mm.

New tubes bend in place when installing the air pipe.

Blocking assembled to establish and fix by bolts of M10*20 to a framework and to connect to a shaft. Install and attach cam elements with M 10 × 70 bolts to the frame and connect them with tyres according to the diagram.

After installation of all elements on the frame, lubricate the gear and rack of pneumatic drive, grease TSIATIM ‒ 201.,