RU215867U1 - ANGULAR CONTACT BEARING CASSETTE TYPE FOR RAILWAY BOX - Google Patents

Abstract

The utility model relates to double-row angular contact rolling bearings used in railway axle boxes. In particular, the bearing is intended for operation as a part of railway bogies under freight cars on the main railway tracks of general and non-public use.

The technical problem solved by the claimed utility model is to ensure a uniform distribution of stresses along the effective length of the contact surface of the rollers.

The technical result is to increase the antifriction properties of the bearing and to ensure a uniform distribution of stresses along the effective length of the contact surface of the rollers.

The claimed technical result is achieved by the fact that in a known angular contact bearing containing an outer ring, inner rings and conical rolling elements placed between them, according to the utility model, the outer surface of the rollers on the generatrix of the cone is made with a convexity of up to 3 microns, while the raceways on the outer and inner rings are made straight, on the inner surface of the outer and inner rings a phosphate coating is made, which is a fine-grained film 2-4 μm thick, obtained in the course of chemical treatment. 3 ill.

Description

The utility model relates to double-row angular contact rolling bearings used in railway axle boxes. In particular, the bearing is intended for operation as a part of railway bogies under freight cars on the main railway tracks of general and non-public use.

Known roller tapered axle bearing for freight cars TBU 150 × 250 × 160 in the standard version according to GOST 32769-2014 https://docs.cntd.ru/document/1200111607 (Figure 2 - Design with a front cover, with three bolts, with plug) containing the base bearing, wear ring, thrust ring, seal, front cover, lock washer, end mount bolt, plug.

Known double-row angular contact bearing for railway axle box (patent for invention RU 2372534, publ. 20.12.2008), containing the outer ring, the inner rings and placed between the conical rolling elements held by the cage. Rings are made of high-strength steel EI347SHD (8X4 V9F2-SHD). The rollers are made of bearing steel ШХ15СГШ. Wear-resistant anti-friction diamond-like coating is applied to the raceways of the rings. The separator is made of reinforced, hardened polymer with solid lubricants. O-rings are installed on the ends of the bearing, which are in contact with the spacer rings, and a hard anti-friction coating HRC from 85 to 95 units is applied to the working surfaces of the spacer rings. A groove is made on the outer ring and there are at least three drainage holes in it. This solution was chosen by the applicant as the closest analogue.

The disadvantages of the closest analogue include the lack of the possibility of smooth rolling of the bearing, since the wear-resistant coating is hard, in addition, in the presence of such a coating, the effective length of the contact surface of the rollers with the raceways is not provided.

The technical problem solved by the claimed utility model is to ensure a uniform distribution of stresses along the effective length of the contact surface of the rollers.

The technical result is to increase the anti-friction properties of the bearing and ensure a uniform distribution of stresses along the effective length of the contact surface of the rollers, which in turn helps to increase the load capacity of the bearing and its service life, reduce the elastic hysteresis in the contact zone of the rollers with the bearing raceways, reduce vibrations during operation of the bearing at maximum speed, increase the speed of rotation of the bearings, reduce the maximum temperature inside the bearing, ensure damping of load fluctuations.

An additional technical result is the expansion of the arsenal of tools for the same purpose, namely the creation of a design of a cassette-type angular contact bearing for a railway box.

The claimed technical result is achieved by the fact that in a known angular contact bearing containing an outer ring, inner rings and conical rolling elements placed between them, according to the utility model, the outer surface of the rollers on the generatrix of the cone is made with a convexity of up to 3 microns, while the raceways on the outer and inner rings are made straight, on the inner surface of the outer and inner rings a phosphate coating is made, which is a fine-grained film 2-4 μm thick, obtained in the course of chemical treatment.

Making the outer surface of the rollers convex with a convexity of up to 3 microns on the generatrix of the cone and simultaneously making the raceways on the outer and inner rings straight with a phosphate coating in the form of a fine-grained film 2-4 microns thick ensures, when the bearing is running in, the pressure of the convexity of the generatrix of the roller cone on the raceways of the outer and inner rings, thereby the profile of the roller deepens by up to 3 microns into the phosphate layer of the forming raceways, which, in turn, begin to completely repeat the longitudinal profile of the roller. Since the phosphate layer is sufficiently loose, it softens the surface of the raceways of the rings and improves the antifriction properties of the surfaces, while ensuring uniform stress distribution along the effective length of the roller contact surface in normal load conditions.

In the proposed design, the rows of rollers take position relative to the raceways of the rings as the phosphate layer is rubbed in, thereby determining the optimal contact points.

The convexity of the roller was calculated constructively and tested in practice, and this convexity is no more than 3 microns, the convexity value should fall within the coverage range - this is 2…4 microns. Eventually, after rolling the bearing, the convex surface of the roller will be in contact with the metal surface of the raceway.

An increase in the effective length of the roller contact, in turn, contributes to an increase in the load capacity of the bearing and its service life. The basic dynamic radial load rating of a radial roller bearing is calculated as follows:

13534,7 Н,

13534.7 N,

where

C _r = basic dynamic load rating;

b _m = bearing type rating factor (value 1.1 for tapered roller bearings);

f _c = material/geometry/size factor;

i = number of rows;

L _we = effective roller length;

α = contact angle;

Z = number of rollers in a row;

D _ψe = average roller diameter.

The importance of the effective roller length L _we is obvious, this is the length of the roller surface that will be in contact with the raceways of the rings, and it directly affects the dynamic load capacity of the bearing.

In addition, ensuring an increase in the antifriction properties of the bearing and ensuring a uniform distribution of stresses along the effective length of the contact surface of the rollers helps to reduce the elastic hysteresis in the contact zone of the rollers with the bearing raceways, reduce vibrations when the bearing is operating at maximum speed, increase the bearing speed, reduce the maximum temperature inside the bearing, providing damping of load fluctuations.

The essence of the utility model is illustrated by the drawings, where in Fig. 1 shows a roller between the bearing rings before the bearing is run in, in Fig. 2 - roller between the bearing rings after running the bearing, in Fig. 3 - an example of a specific implementation of a cassette-type angular contact bearing for a railway axle box (general view of a double-row bearing).

A cassette-type angular contact bearing is a double-row bearing containing an outer ring 1, inner rings 2 and conical rolling elements 3 placed between them. The rollers 3 are made with a convexity of not more than 3 microns on the generatrix of the cone. Measurements of roller diameters are carried out in three sections at a certain distance along the roller axis. The raceways on the outer 1 and inner 2 rings are made straight. The inner surface of the rings at the final stage of manufacture undergoes chemical treatment, as a result of which a salt (phosphate) coating is formed on their surface, which imparts the necessary characteristics (high adhesion, electrical insulation, etc.). Fine-grained films 2–4 µm thick are formed on the polished steel surface.

When the bearing is running in (Fig. 2), pressure is created by the bulge of the generatrix of the roller cone on the raceways of the outer and inner rings, thereby the profile of the roller deepens by up to 3 microns into the phosphate layer of the generatrix of the raceways, which in turn begin to completely repeat the longitudinal profile of the roller, which ensures uniform distribution of stresses along the effective length of the contact surface of the rollers in the normal load mode.

In FIG. 3 shows a general view of a double-row bearing (an example of a specific implementation). The cassette-type bearing in dimensions 150×250×160 corresponds to GOST 32769. The cassette-type bearing in dimensions 150×250×160 is pressed under the adapter onto the axle neck of the wheelset of the RV2Sh-957-G type. The bearing presented in the example of a specific implementation includes: outer ring 1, inner ring 2, rollers 3, distance ring 4, polyamide separator 5, rear thrust ring 6, polymer gasket 7, seal 8, end cap 9, lock washer 10, end fastening bolt 11, plug 12. The bearing is mounted on the axle of the wheelset using end cap 9 and bolts 11 (M24 in the amount of three pieces or M20 in the amount of four pieces).

The bearing is adjusted for axial clearances, inner ring hole diameters, filled with grease and has built-in seals that prevent water, dust, and dirt from penetrating into the bearings.

To prevent the formation of fretting corrosion between the labyrinth and the ring of the inner back row of the bearing, a polymer gasket is used.

The transfer of loads from the bogies to the wheelsets is carried out through adapters that are freely installed on the outer rings of the bearings.

Claims (1)

Cassette-type angular contact bearing containing an outer ring, inner rings and tapered rolling elements placed between them, characterized in that the outer surface of the rollers on the generatrix of the cone is made with a convexity of up to 3 microns, while the raceways on the outer and inner rings are made straight, on the inner surface of the outer and inner rings, a phosphate coating is made, which is a fine-grained film 2-4 μm thick, obtained in the course of chemical treatment.

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