Maintenance parts with plain bearings

Boxen knot sliding bearings in operation the most susceptible to failure in comparison with other parts of cars. More than 60% of all marriages in the rolling stock related to boxwood Grenier sliding bearings. Therefore, this unit requires constant attention from the employees point of maintenance of cars, forcing them to constantly improve methods for identifying and troubleshooting axle unit.

The most perfect way to detect failures is an advanced method PTO station Moscow-sorting Moscow-Ryazan road. This method allows you to troubleshoot bux on external features and details of both the axle boxes, and other components running parts: spring kits, wheelsets, bolsters etc. The method is especially valuable because it allows you to detect and remove the causes Grenier boxwood cars before the Grenier. This was particularly important in the 80's, when the warranty shoulders nonstop freight train reached 250-300 km and more with increasing speeds and loads.

Identify signs and causes Grenier boxwood with plain bearings made up mainly of three elements: the train meeting immediately; detect faults in appearance axle unit, wheels and parts carts, inspection after opening the upper parts of cervical axis, bearings, lubrication and tamping material.

When meeting with the trains run on a thought, a specific smell hot grease, a peculiar sound (beeping) reveals boxes, are already having significant heat. In addition, at a meeting with the course can be increased more than the usual lateral movement of the side frame truck while driving. This usually points to the destruction of babbit bearing pouring from the front or back of the fillet, because the run bearing in this case increased. Identified defects on the train on the running surface of wheels, such as slides, Navara, uneven rolling, cutting comb, are also signs of bearing failure, as can be the cause of premature failure of babbit layer.

When viewed from the train after stopping the knowledge of external signs of bearing failure will quickly find them.

The external signs of bearing failure are:

traces of oil thrown on the wheel center and the outside of the Books, which is characteristic of boxwood tucked Polster. This indicates a worn bearing babbit layer. Between predpodstupichnoy part of an axis and dust washer for axle box bearing sediments appears a gap through which the motion of the car and is the axial oil sloshing from the housing;

touch the back of the upper parts of the body end wheel hub, which indicates deterioration or spalling from the back babbitt bearing fillets. In this case, either the visible net shiny surface of the rear wall of the housing and the axle box end hub if the bearing is moved in the direction of the axis of the neck collar, or in between the gap is completely absent, if the bearing is moved in the opposite direction;

presence of circular annular bands (one large or two narrow) at the top of the ridge. Strip located on the crest of a wheel, and the crest of another of the same wheel set is dark, indicating a bearing failure on the opposite side;

undercut vertical ridge;

Car wheel rolling circle of 6 mm, the presence of the crushed, local broadening rim;

discoloration boxes, in the winter snow melt on the upper parts or body appearance on her icicles.

With the destruction of the bearing babbit layer increases lateral movement of the side frame truck. This also results in abnormal operation bolster, friction shock absorbers and other parts. In trolleys CRI-HZ-0 causes these cases turns on the surface of the upper forming end-lane spring, there may be traces of mutual displacement of friction wedges and springs or traces in the form of a wedge, facing the top down, the friction from rubbing strips on them friction wedges.

In trucks MT-50 and UV3 at extended transverse moving the side frames appear traces of mutual friction bolster and side frame truck with the formation of metal chips or dust, wear bolster on the upper end planes DIP springs, and the displacement of the individual sheets in elliptic leaf springs and break its tip.

In addition, signs of destruction babbit layer bearing trolleys all these types is the presence of metal shavings, dust or rust between pyatnikom and glides. Different types of spring sets in the cart or kink springs and elliptic springs cause increased wear of the bearings, as in this case, there is an uneven distribution of the dynamic loads on the bearing. Most frequently fail those bearings, from the location of which are high dynamic loads, ie where a smaller number of springs, not elliptical spring or instead put the spring, etc.

Uneven wear on babbit layer along the bearing points tilt the housing upper part. If the upper part of its front part is raised, then the bearing is increased wear babbit pouring from the back of the fillet, and if omitted, from the front of the fillet.

Besides external, there are also the so-called logical signs under which requires a thorough examination of bearings, as in these cases the probability of failure increased. These characteristics include: long-term (six months or more) the operation of the car after the periodic maintenance, the presence of chalk marks on the body 0 repeated repair axle unit on the previous PTO, filling one axle box wagon rolls if Polster in the other, etc.

In the presence of external and internal examination of logical signs of boxwood can make a final conclusion on the nature of the fault axle unit and decide whether to repair.

Inspecting cars after a long stay at the station when boxes, grevshiesya in transit, has cooled down, except these signs bearing failure, it should be borne in mind, such as the dark color of the axis of the neck or the appearance of discoloration on her butt, butt, or the presence of dry it circular roller hardened grease with a crust brown. Parts with the presence of such features is extremely suspicious and require podemki to extract the bearing and overhaul his neck axis, insert and Polster. In this necessarily should identify and correct the cause of the increased heating boxes, if it has not been eliminated in the previous MAP.

If the bearing has a low approach (ie the distance from the axis of the neck collar to the upper surface of the bearing housing is not more than 26 mm.), The visible material podbivochnm babbit or bronze dust, and oil has babbit chips, these signs indicate deterioration babbit layer bearing.

When internal inspection axle box should also pay attention to the nature of the lubrication neck axis.

In places wear babbit layer axial bearing oil gets out thinly and neck because of the friction of the bronze reinforcement has a bright shine with a golden hue. Babbitt points on breakaway oil goes even layer of uniform thickness, the crack - a trickle, the sink - the band, equal to the width of the diameter of the shell.

Found on the front end of a double or casting babbit located above shoulder mark from contact with collar neck axis points to earn extra money pouring babbit the back fillet. A similar fault, you should generally expect and • in the bearing on the opposite side of the wheelset. Babbit bearing wear layer at the back of the fillet is also possible in the case of a gap of 15 to 20 mm between the cervical collar wheel pair and the end of the bearing.

The crack in the middle of the end bearing can pass along the bearing and end production or chipping babbitt the back fillet. This bearing should be removed and inspected.

Grenier cause the bearings may be the so-called glazing. Color babbitt with glazing yellow, and its surface has a sink. Glazing bearing - is the result of process upsets in babbit-casting office depot (incorrect drawing of the charge and the failure temperature regimes).

If it has no bearing on the refrigerator or clearance diameter of the neck axis on the work surface reflectivity babbit layer appears as the oil enters the bearing in short supply or not received at all. The surface of the neck axis to spiral out of the bearing, in this case, almost dry. Also, if the diameter of the bearing is less than acceptable, then the height of the bearing surface in the upper middle part of the cervical collar axis increased.

Mirror can not shoot scraper. The surface of the bearing should pour cold axial oil, then check its compliance with the diameter of the neck axis. To do this, fill the bearing babbit wiped clean ends, along the axis of oil is applied four points and set the bearing on the neck line. If the bearing recess reveals that all four points separated oil, then put the bearing can not replace, you give the refrigerator. If at least one point is not sold out, you need to pick up another bearing.

Since not all bearing failure can be detected by visual inspection, to detect hidden defects senior MP viewer cars Batin offered special hook-a pattern that has a hook height of the heel to the tip of 36 mm. The tip of 2 mm thickness is used to check the refrigerator, state of the rear bearing fillet, properly fit it on the axis of the neck, etc. Rack is designed to measure the length of the layer of babbit bearing. The hook is put the rear bearing and fillet a gap between the counter and the front of the bearing points to spalling or wear babbit layer at the back. Hammer is designed for tapping inspection covers a roller axle-boxes, as well as opening and closing the lid from boxwood with sleeve bearings. He machined separately quenched and welded.

For measurements provided yardstick length of 150 mm. Handle ends crowbar to test the mechanism of automatic couplers on samorastsep. It has three risks: a distance of 70 mm and 120 mm from the end to determine the congestion of cars and average to check on the car size of 100 mm.

From the proper loading of the car to a great extent on the normal operation of bearings. Overloading the car, uneven load distribution along the length of the car can cause damage to various pouring babbit bearing, bending neck wheel pair and even fracture it. Therefore, control of the correct placement of cargo in the car is important. To determine the distance between the overload checked bolster truck and upper chord cast side frame on the outside in the middle of spring group. In the capacity of 63-64 tons of cars, this distance should be for trucks MT-50 and UVZ not more than 70 mm, for trolleys KZ-CRI-0 is not more than 117 mm, and a lifting capacity of 65-66 tons of cars accordingly does not exceed 71 mm and 120 mm .

More convenient to define an overload of the car using a special template developed in the train depot Vyazma Moscow road. Every 3 m overload train on trolleys MT-50 and UVZ correspond to about 1 mm deflection spring group, and on trucks CRI-HZ-0 - 2 mm. When congestion control is necessary to check the distance of the center of each spring group. If there is a difference in size between the trolleys or their parties, it shows the uneven distribution of load in the car. The cars that have seen an overload or uneven loading of the cargo shall be followed by an obligatory check-weighing.

Consequence of overloading the car or the uneven distribution of the load on the wheel sets can be extruded babbit layer. In this case, the hook is rejected during his side faces along the bearing. The same effect leads improper selection of the bearing, as well as reducing the amount of calcium and sodium in the babbitt for violating its smelting process. Bearings with a layer of crushed babbitt for this reason should be replaced. Note, however, that the Extrusion babbit casting can occur as a result of cervical cone axis. In this case, squeezing occurs either in the front or in the back of the bearing and the hook freely enters the bearing in the part where the babbit fill is crushed. Wagons of having a tapered neck axis should be uncoupled and submitted for repair to replace the wheel sets.

In a study of the rear hook fillet bearing wear on her show found with pointed edges babbit pouring. Bearings with a diameter larger than allowed for this neck of the axis can be identified as a hook. The hook in this case is free to the bearing on both sides along its entire length.

Indicate a problem with the lack of liner or larger gap between the ceiling and the upper part. With these features liner replaced. • At the same time, be aware that during normal operation of the liner marks from contact with the ceiling of the housing upper parts are visible in the middle part of the length of 65-105 mm.

Normal operation of axle unit is largely dependent on proper compliance with all standards and requirements of refueling boxwood. Tamping material should be clean, intact and well soaked in seasonal axial oil. Amount of oil in the axial Books, tucked rollers is normal, if you click on them hook oil collects in the hole formed at the same time, and tucked Polster, if the oil is less than the bottom of the axle-box slot for dust washer or does not reach the axial cervical collar for 20 25 mm, and if the distance between the level of oil and the internal axial ribs upper parts is within 30-35 mm. This is the distance you control the universal hook template. For this hook with a cutting edge is applied to the edge stiffness boxes, and his heel should lightly touch the axial oil.

Inspecting Polster, must pay attention to faulty brush frame and clamping force of the upper plate with a brush to the neck axis. When running on the edge polsternoy brush hook for metal or metallic sound is audible, then, is damaged or displaced due to breakage of fastening polsternaya brush. Substitute should also Polster with defective frames and having sagging springs. To determine the drawdown springs polsternuyu brush with the top plate squeeze hook. In Polster with sagging springs polsternaya brush after this to the neck axis is not pressed.

Tucking the upper part Polster, must pay attention to the condition of its springs, since their compression pinched coils, resulting Polster does not touch all his brush with the neck axis, and only part of it. The oil in this case is not supplied or supplied in insufficient quantity, resulting Grenier bux on the way.

When the upper part is filled rolls, to avoid subsidence, they must be sealed under the neck axis.

Winter is particularly unfortunate for axle box with sliding bearings, because at this time of year there are additional causes of faults in the nodes of box. It is, first of all getting into the upper parts of snow due to loose-fitting lid, accumulation of moisture in the melting of snow in the thaw of ice and freezing water. The presence of water leads to the flooding of the axial oil, resulting in polsternye brushes and rollers, soaked with water, lose the ability to sum up the oil to the neck axis. The presence of water in the material is determined by tamping oily reddish patina on the face and neck axis of the inner walls or on the upper parts tamping material, and in the axial oil - from the appearance of the water droplets on the surface by shaking his hook. Flooding boxwood tucked rollers, easy to identify, by pushing the hook. In this case, they will be squeezed out of the water.

In the formation of ice in the journal boxes in it freezes the lower part of the plate and coils springs Polster, which is why he loses mobility, but with a substantial amount of ice occurs vmerzanie and wicks polsternoy brush. Vmerzanie wicks especially dangerous, as in this case, the upper plate with a brush Polster pulled down so completely disconnecting the supply of lubricant to the neck axis. Finding the BUKS water, snow or ice shall be removed using special devices, syringes, or scrapers, and add fresh axial oil.

To remove water from the housing on some PTO used a special device, which is a tube with a curved appendage, which is wearing tight rubber bag. For pumping water curved end of the tube is lowered into contact with the upper part to its bottom, rubber bulb is compressed and finger covering the lower opening of the tube. After that, let the pear, and it returned to its original state, sucking water from the housing. Then the bottom of the tube is opened, and the water flows by gravity into a special container.

When watering tamping material or freezing upper part refill. In winter Login Forgot often seen instead of the axial oil thick mush mix with snow. Bushings are also refillable. Should be refilled and dirty boxes, which are easily identified by the presence of brown grease with mechanical impurities at the end of the neck axis. In the event of a scorched tamping material upper part completely refilled, and you must see the neck axis and bearing after podemki.

During the inspection and repair of axle unit on the train, stopped at intermediate stations on the testimony PONAB when Bushings already heated to a given temperature, the solution of long-distance must be taken depending on the heat and the distance to the nearest vet. It should be remembered that from the beginning of silkworm eggs to break the neck axis at full load and under the most unfavorable conditions of the other car can pass at the set speed a distance of about 50-60 km.

If the neck axis is heated up to 140-150 degrees, and bearing condition and tamping material is satisfactory, a sufficient refill upper part and train can go next to the set speed. Grenier, usually with long-distance stops, but the locomotive crew should be warned of the need to constantly monitor the axle boxes on the way.

If the smoke bush, neck axis is heated to 240 - 250 degrees, pouring babbit bearing crushed, tamping material has begun to scorch, a car should be raised and check the neck axis. In the absence of any defects in the neck axis (waviness, scratches, burrs, etc.), let it cool down to a temperature of 100-120 degrees, in any case, without the need for cooling with snow or water, replace the bearing and fill the upper part clean tamping materials and fresh axial oil. Next train may proceed at a fixed rate or somewhat reduced depending on the load of the car in which it was Grenier boxes, to the nearest vet. Locomotive crew of this should provide increased monitoring of basking upper part.

Wagons with the neck of the axis is found defective, and with glowing boxes, melting out all or part of the bearings, it is necessary to unhook the train.

Sometimes, when the train stops unexpectedly due Grenier axle box for the early release of driving basking upper part is filled with grease marks HA, then train with reduced speed can result to the nearest station. For the upper part of the refill to the tamping rollers, and then between the neck axis and a side wall of the housing axle box on the opposite side of the train, lay about 400 g antiavariynoy grease. All boxes, tucked antiavariynoy zmazkoy, in transit, regardless of their condition should be seen from the train at the seasonal perezapraleng PTO axle oil, and neck axis and bearings inspected after podemki.