Details axle unit and the possible failure

For normal operation, the bearings should be provided with adequate sealing boxes, eliminating her from entering the dust, mechanical impurities, moisture, snow, etc. Therefore, on the walls of the front opening, called the mirror axle box and close the lid, there should be no leaks.

In parts with plain bearing four-wagons used sheet steel axle-box lid with rubber seal.

The cover is attached to the axle boxes of roller length 225 - 230 mm, which in turn is to prevent from falling out the cotter pin is attached to the washer.

Rubber washers used to seal the housing wall boxes, made of frost-resistant rubber. To give greater rigidity and ease of production in the upper part washer reinforced steel core, which is a Fancy-curved rod of annealed wire with a diameter of 6 mm.

The most critical parts of the car axle unit is bearing that directly all of the loads acting on the upper part, transferred to the neck axis. In addition, the motion of the car between the bearing and the neck axis arises considerable friction. Therefore, the bearing should be strong enough, and its surface in contact with the neck axis, made of soft and at the same time durable alloy. Therefore, the three-layer bearings are made, consisting of a steel, bronze and babbit reinforcement fill. Bearing covers neck axis angle of 120 degrees (1/3 of the circle). Specific pressure attributable to the bearing reaches 3.7 x -4.0 MPa (37 -40 kg / sm.kv.).

A small number of common upgraded bearings that in order to reduce the surface pressure had an increased angle of wrap, but be uncomfortable with change in VET more difficult to fit to the neck axis and much more expensive to manufacture because of the great weight, are not widely used.

Part of the new bearings, coming into operation, two-layer: bronze reinforcement they lack, and babbit layer is attached directly to the steel hull.

Boxen liner, disposable between the ceiling and the bearing axle boxes, designed to hold the bearing in the top of the upper parts and facilitate the replacement of its recess. In addition, the presence of the liner greatly reduces wear on the ceiling and upper parts ensures even distribution of the load on the bearing. Liner made of steel grades St0 St5-stamping or casting.

Structurally boxen assembly with roller bearings sealed more than plain bearings. In the process of grease from the housing does not flow and is replenished only at autopsy axle box covers, mounted on bolts. Sealing Bushings staging reached between the cover and the housing upper parts of the gasket. On the pads installed and inspection covers, available on some of the boxwood. At the rear axle box seal creates a maze and labyrinth ring formed recesses back of upper part. Normal operation of roller bearing axle boxes with cover if it laid down a fixed number of grease LZ-CRI with no mechanical impurities.

In parts with roller bearings have remote ring if mounted on the neck of cylindrical and spherical bearings. Labyrinth ring always put on a hot landing. Complete details with roller bearings has an end nut with locking rod, bolt or washer fixing, also bolted. Last mount after installing snap ring. Bolt lock plate fixing washers after securing fixed wire. In parts with four-friction bearings of cars the most common injuries are various cracks and spalling. Cracks in the top of the allowed length of 150 mm, and the cracks in the lower part is not permitted at all, because they can flow through the axial oil. Be replaced as boxes, with the tide to roll spalling of box covers and damaged the back wall, which do not hold the sealing washer or axial oil may leak. Sign of cracks through which follows the axial oil, is the accumulation of dirt on the upper part. The presence of such dirt or stains of oil on a wheel also points to breakaway in the back of the upper parts or defective discs. Not authorized for use with cars stalled, with the housing slump or sag, so that contact with the bushing axis and fracture shoulder or hard shoulder to the liner.

Details of roller bearings may be damaged as a result of which, boxen unit heats up. Heating boxwood with roller bearings due to improper installation or configuration of bearings when not provided the necessary difference of axial and radial clearances. This happens in case of damage of bearing, because of external or internal cracks rings, cracks and splits rollers, separators, with poor lubrication of box when it let metal or other impurities. Violation of the axle unit also occurs during spontaneous unscrewing bolts, depositions or the lock plate fixing washers, unscrewing fixing nut.

Heating the upper parts with roller bearings can take place and, if not build trucks when skewed frame wrongly fixed shpintony etc. Decision on the possibility of further movement of the car with a heating Buks takes foreman or master, having the right to produce a full audit of boxwood, with roller bearings, after opening the upper parts and control parts axle unit.

Never admit to following cars, which do not have, kinked or bent axle-box cover, missing or lost elasticity of box spring covers, resulting in a gap between the lid and the mirror axle box more than 5 mm, and do not provide sufficient tightness upper part. In these cases, no cap should be put, and replace defective.

Boxen liners should not be bent, have spalling or cracking. Wear of the bearing surface, in which the liner loses its slightly convex form is not allowed.

Be replaced bearings, which is cracked and crushing babbit layer, deterioration or spalling babbit casting, crack or spall case. You also need to replace the bearings with any other faults that cause friction Books, such as excessively large thickness of the rear collar bearing, uneven wear shoulder body, causing bearing warping, bad boring babbit pouring.