RU2651961C1 - Radial sliding bearing - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to machine parts, in particular to the radial sliding bearing structures used in high speed rotary systems, for example, compressors, turbines, electric generators. Radial slide bearing comprises housing (1), at least one segment (2) mounted in housing (1) by means of pin (4) located in coaxial holes of housing (1). Groove (1a) is formed on the inner surface of housing (1). Coaxial holes for pins (4) on housing (1) are made in the area of groove (1a). On segment (2) there is trunnion (2a) with a hole. Mounting of segment (1) in housing (2) is carried out by means of pin (4) located with a gap in damper sleeves (3) fitted with a gap in the coaxial holes of housing (1) and passed through the hole of trunnion (2a) located with the axial and radial gaps in the groove of housing (1). Ring protrusion (4a) having a spherical shape, which is located with a gap in the trunnion (2a) hole is provided on pin (4).

EFFECT: ensuring of trouble-free operation of high-speed rotor systems of machines by providing damping of the vibrations of rotating parts installed in bearing by damping elements of bearings.

4 cl, 8 dwg

Description

The invention relates to machine parts, namely, to designs of radial plain bearings used in high-speed rotary systems, for example, compressors, turbines, electric generators.

A bearing is known, comprising a housing, self-aligning segmented bearings placed in the housing relative to the male shaft, mounted with a radial clearance relative to the shaft, each of the bearings is fixed to the end of an elastic element made of high-damping steel, and the second end of the elastic element is attached to a plate fixed to the outer surface corps.

(see RF patent for utility model No. 61820, class F16C 17/03, 2007).

The disadvantage of this bearing is that in order to ensure the specified damping characteristics, it is required to provide significant dimensions of the damping elements. However, under the conditions of real structures, as a rule, there is a deficit of structural space, which leads to the fact that the given damping characteristics are not fully ensured. In addition, materials with high damping ability have significant limitations on the temperature of application (akin to the Curie points for magnetic materials), which makes it impossible to provide damping in cases of operation of such bearings at high temperatures, for example, when using them for gas turbines.

Known segmented radial plain bearing containing self-aligning segments located inside the bearing housing around the circumference of the shaft and covering the trunnion of the latter with a radial clearance, each of the segments is mounted on a separate support mechanism that interacts with the segment through an element with a spherical surface, each segment includes a bearing and antifriction elements in the form of plates, the supporting mechanism of each segment includes a ball pin interacting with its spherical end the surface of the recess made on the outer surface of the supporting element, a spring cup made with the possibility of elastic deformation along its longitudinal axis, which is provided at the open end with a flange designed for detachable connection with the bearing element of the segment with the installation of adjusting washers, while in the bottom of the spring cup made through axial hole covering the area of the spherical finger adjacent to the spherical end of the latter, and interacting with its part with the surface of the sphere of a triangular shape, expanding towards the segment, with the spherical end of the ball pin, a support pin screwed into the through radial threaded hole of the bearing housing, with a through axial hole adjacent to the inner end of the pin, the area of which is paired with the cylindrical end of the ball pin, and adjacent to the outer the outer end of the region of smaller diameter - with the screw shaft screwed into a blind threaded axial hole in the end face of the cylindrical end of the ball pin until the head of this screw is mated to the outer end of the support stud.

(see RF patent No. 2474737, CL F16C 17/03, 2010).

As a result of the analysis of the implementation of this bearing, it should be noted that its design is very complex, radial dimensions are significant. The use of a friction ring clamping the hinge of the self-aligning segment by means of a glass provides some damping of the angular vibrations of the segment due to friction in the hinge, but does not completely provide dispersion of the vibrational energy of the rotor system in the radial direction.

Known elastic damper segmented plain bearing, comprising a housing mounted in it with a clearance of a cage, connected to the housing by means of elastic elements made in the form of pins, each of which is installed in the corresponding hole of the cage and in the holes aligned with the end walls of the casing, self-aligning relative to segments covered by the shaft, interacting with the inner surface of the cage, each self-aligning segment is made with a hole in which the bolts are placed t, it passes through aligned openings in the end walls of the housing, wherein each pin is placed in the hole with clearance caster segment whose size is larger than the size of the gap between the housing and cage.

(see RF patent No. 2406890, class F16C 17/03, 2010) - the closest analogue.

As a result of the analysis of the implementation of the known bearing, it should be noted that the elastic elements made in it in the form of pins, on which the cage rests, are limited in length by the axial dimension of the bearing, which, if necessary, ensures low rigidity to high voltages, leading to fatigue failure of the pins and exit bearing out of order. The ability to damp the vibrations of the rotor system, as follows from the invention, is ensured solely due to the circulation of the lubricating fluid in the annular gap formed by the housing and the cage. If low viscosity media or gas are used as a lubricating fluid, such a damping method is insufficient. These problems are eliminated by the proposed technical solution.

The technical result of the present invention is the provision of trouble-free operation of high-speed rotor systems of machines by providing damping of vibrations installed in the bearings of their rotating parts by the damping elements of the bearings.

The specified technical result is ensured by the fact that in the radial plain bearing containing the housing, at least one segment mounted in the housing by means of a finger placed in the coaxial holes of the housing, new is that a groove is made on the inner surface of the housing, coaxial holes for the finger on the housing made in the groove area, on the segment there is a pin with a hole, and the segment is mounted in the housing by means of a pin placed with a gap in the damper bushings installed with a gap in coaxial openings of the housing, and a trunnion passed through the hole, arranged with axial and radial gaps in the groove of the housing, wherein a finger has an annular protrusion having a spherical shape, which is located with a gap in the opening of the trunnion, while between the damper located in the coaxial openings of the housing additional damper bushings can be installed with the bushings and the body, milling can be performed on the fingers to reduce its cross section, and cuts can be made on the bushings.

The essence of the claimed invention is illustrated by graphic materials on which:

- in FIG. 1 - radial plain bearing, general view, axonometric projection with a partial section of the housing;

- in FIG. 2 - node installation segment in the housing, axial section;

- in FIG. 3 - node installation segment in the housing using additional bushings, axial section;

- in FIG. 4 - finger, axonometric projection;

- in FIG. 5 - damper sleeve, axonometric projection;

- in FIG. 6 and 7 - diagram of the deformation of the elastic elements of the bearing under the action of radial loads on the segment;

- in FIG. 8 - additional damper sleeve, axonometric projection.

The radial plain bearing consists of a housing 1 having, mainly, a ring shape, on the inner generatrix of which a groove 1a is made.

The bearing is equipped with segments 2. The number of segments may vary. So in FIG. 1 shows one segment, but this does not mean that their number cannot be different.

Segment 2 (each segment, if there are several of them) is equipped with a trunnion 2a, which, when mounting the segment 2 in the housing 1, is located in the groove 1a of the housing 1. The groove 1a can be made in the form of a ring (ring groove) and the trunnions of all segments are located in it. For each pin on the inner surface of the housing, a separate groove 1a can be made. For the developed bearing design, this is not important.

To carry out the installation of segment 2 in the housing 1, a through precision hole is made in the axle 2a (not indicated by the position), and in the housing 1 in the region of the groove 1a there are two holes located on the same axis (not indicated by the position). Damper sleeves 3 are installed in these coaxial openings of the housing. Each sleeve has a cylindrical part, with which it is located with an axial clearance “c” in the opening of the housing 1, a flange at one end and a centering belt at the other. Damper bushings 3 are made of an elastic material, for example, spring steel (65G, 60S2A).

When mounting segment 2 in the housing 1, the damper bushings 3 are installed in the coaxial holes of the housing until the inner ends of their flanges contact the ends of the housing. Finger 4 is passed through the holes of the damper bushings 3 and the hole of the axle 2a with an axial clearance “d” and secured against axial movement by means of washers (not indicated by positions) in contact with the outer ends of the flanges of the damper bushings 3.

In the central part of the finger 4 there is an annular protrusion 4a of a spherical shape. In the assembled position of segment 2 in the housing 1, this protrusion is located approximately in the central part of the precision hole of the pin 2a. Finger 4 is most expediently made of an elastic material, in particular, spring steel, for example, 65G, 60C2A.

The widths of the spigot 2a and the grooves 1a are correlated in such a way that when the trunnion is placed in the groove, structural axial clearances "k" and "m" are maintained between the end surfaces of the trunnion 2a of segment 2 and the walls of the groove 1a, allowing segment 2 to perform axial movement along the finger within these gaps.

As already noted above, in the assembled position of segment 2, the annular protrusion 4a of the finger 4 is located approximately in the central part of the precision hole of the pin 2a. The pin of the segment rests on this annular protrusion 4a of the finger 4 and, due to the spherical surface of the protrusion 4a, the segment is rotatable relative to this annular protrusion.

Thus, the installation of the segment in the housing with the possibility of its axial movement and rotation, allows the self-installation of the working (supporting) surface of segment 2 relative to the shaft surface (not shown) within the working clearance of the bearing. The finger 4 and damper bushings 3 in the assembly form an elastic bearing system.

To reduce the rigidity of the elastic system on the finger to reduce its cross-section, milling 6 (Fig. 4) can be performed, and on the bushings 3, weakening slots 7 (Fig. 5).

In the case when it is necessary to further reduce the rigidity of the elastic system, additional damper bushings 8 can be installed in the coaxial openings of the housing between the bushings 3 and the housing 1 (Fig. 3, 8)

Radial plain bearing operates as follows.

When designing the bearing suspension of the rotor of a high-speed machine, a rigidity sufficiently low is laid in order to increase its (rotor) intrinsic bending frequency (close to a free-weighted form). Fingers and bushings used in the construction of the bearing serve this purpose, which, as already noted above, together form an elastic bearing system.

During the operation of the equipment, when the rotor shaft rotates, the segments 2 due to arising moments have the possibility of a turn on the protrusions 4a of the fingers 4 within the gap between the spherical surface of the protrusion 4a of the finger and the wall of the hole of the pin 2a, which ensures self-installation of the segment (s) 2 relative to the shaft.

Segment 2 (each segment), carried away by the rotor shaft, vibrates within the design gaps "f" and "e". The gaps "f" and "e" in this case play a protective role, limiting the movement of the elastic elements of the bearing. In FIG. 6 shows the deformation of the elastic elements of the bearing when the segment moves towards the axis of rotation of the shaft installed in the bearing, and in FIG. 7 when moving from the axis of its rotation. Under the action of forces and moments, the damper bushings 3 and the finger 4 are elastically deformed within the structural clearances "c" and "d" (Fig. 2), thereby forming an elastic system that effectively damps vibrations. The deformation of the elastic elements causes the conjugate movement of the ends of the parts. In this case, damping due to friction will occur at the ends A of the housing. Additional damping will occur due to friction at the ends of the housing B when the segments are displaced in the axial direction under the action of operational loads.

The dimensions and cross-sectional shape of the damper bushings 3 and the fingers 4 can vary within wide limits, providing the estimated elasticity of the bearing.

It is also very important that, having high damping characteristics, in the bearing, unlike analogues, the radial dimensions are practically not increased, which significantly increases the area of its use.

Claims (4)

1. A radial plain bearing, comprising a housing, at least one segment mounted in the housing by means of a finger located in the coaxial holes of the housing, characterized in that a groove is made on the inner surface of the housing, coaxial holes for the finger on the housing are made in the groove region of the segment there is a pin with a hole, and the segment is mounted in the housing by means of a finger placed with a gap in the damper bushings installed with a gap in the coaxial holes of the housing and passed through the holes trunnions disposed with axial and radial clearance in a groove of the housing, wherein the finger is formed an annular projection having a spherical shape, which is located with clearance in the bore of the stud. 2. The radial plain bearing according to claim 1, characterized in that between the damper bushings located in the coaxial openings of the housing and the housing, additional damper bushings are installed. 3. The radial plain bearing according to claim 1, characterized in that milling is performed on the fingers to reduce its cross section. 4. The radial plain bearing according to claim 1, characterized in that the slots are made on the damper bushings.

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