RU2595237C1 - Segment of sliding support - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to machine building and can be used in all industries both main element and axial and radial supports operated with forced feed of lubricant. Lubricant can be used either grease, either liquid or gaseous. In last case proposed design can be used in supports of machines intended for operation in extreme conditions: in aggressive media at high or low pressures and temperatures. Segment of sliding support consists of two parts moving to take up load on rotor side, and stationary one connected with machine body. In fixed part there is channel for supply of lubricant from source, and in movable part of segment there are channels for supply of lubricant in working gap of support, i.e. in gap between working surface segment and shaft neck or rotor foot. Segment also includes elastic support element made in form of flexible membrane of annular shape. Inner edge of membrane is attached to back surface of movable part of segment, wherein in fastening element there is channel for supply of lubricant in movable part from cavity in fixed part. Outer edge of membrane is connected to fixed part of segment, wherein membrane with cavity forms flow chamber. In centre of fixed part bottom there is threaded hole to allow access to fixing element during assembly and disassembly of segment structure. In operating condition of structure hole is tightly closed with screwed plug.

EFFECT: technical result is provision of self-adjustment of movable part of segment, elimination of leakage of lubricant from inner cavity into environment, improving vibration isolating properties of support with disclosed segments.

1 cl, 4 dwg

Description

The invention relates to the field of mechanical engineering and can be applied in all industries as the main element of both axial and radial sliding bearings working with forced supply of lubricant. Grease can be used either grease, or liquid, or gas. In the latter case, the proposed design can be applied in the supports of machines designed to work in extreme conditions: in aggressive environments, at high or low pressures and temperatures.

One of the main tasks that must be solved when creating a gas or hydrostatic support is the development of a self-aligning fastening of a segment that can provide vibration resistance, self-alignment of a segment when the shaft is distorted, and no grease leaks from the internal cavity of the support directly into the environment.

In the monograph I.L. Shishkin “Turbomachines on gas supports” (Far Eastern University Press, Vladivostok, 1985) on page 107 describes the design of a thrust gasostatic bearing with a support element in the form of a round elastic plate fastened along the outer edge with the bearing housing, as shown in Fig. . 1. In the central part of the plate there are holes for supplying lubricant to the working clearance of the support formed by the plate and the fifth rotor. The compressed gas from the power source first enters the flow chamber formed by the bearing housing and the elastic plate, then through the throttling holes in the plate enters the working gap, forming a carrier gas cushion, and from there it enters the environment. Under the action of the pressure difference in the flow chamber and in the working gap, the plate bends, as shown in FIG. 1, therefore, the carrying capacity and rigidity of the support are small, which can lead to contact of the plate with the fifth rotor during its rotation, which is unacceptable for operational safety reasons. In addition, the flow rate of compressed gas consumed by such a support significantly exceeds the flow rate required for the operation of a conventional gas-static support of the same carrying capacity.

In the leading technical material “Calculation of Radial Gas-Static Bearings of Nuclear Power Turbomachines” (RTM 108.129.101-78, NPO Central Boiler-Turbine Institute, Leningrad, 1978) in the table. 3 on pages 45, 46 the basic types of self-mounted fasteners of the liners (segments) of gas-static supports to the machine body are presented. Based on the analysis of patent materials, the authors of RTM recommend using a suspension or a pair of “sphere in sphere” depicted in FIG. 1 as elements of self-installation of inserts (segments) of heavily loaded and large-sized gas-static bearings of cardan bearings. 2. However, these self-installation elements have the following disadvantages:

- during prolonged operation, these elements containing dry friction pairs are at risk of setting;

- the connection of the segments to the lubricating pipelines can interfere with self-installation and cause dangerous distortions.

The construction proposed in the Czechoslovak Patent No. 116766 shown in FIG. 3, where a bellows is used as an element of self-installation.

The construction shown in FIG. 3, adopted as a prototype in this application.

The disadvantages of the prototype design include too much flexibility, or, what is the same, insufficient rigidity of the self-alignment element when the liner is displaced, which can lead to distortions and unacceptably large values of the rotor and stator alignment.

The construction of the segment shown in FIG. 4, consisting of two parts: movable 1, perceiving the load from the rotor side, and stationary 2, connected to the machine body. In the fixed part there is a channel 3 for supplying lubricant from the source, and in the moving part of the segment channels are made for supplying lubricant to the working clearance of the support, i.e. into the gap between the working surface of the segment and the journal of the shaft or fifth rotor. A distinctive feature of the claimed design is an elastic supporting element 4, made in the form of a flexible membrane of annular shape. The inner edge of the membrane is bonded to the back surface of the movable part of the segment, while in the fastening element 5 there is a channel for supplying lubricant to the movable part from the cavity existing in the fixed part. The outer edge of the membrane is connected to the fixed part of the segment, while the membrane forms a flow chamber with the cavity. In the center of the bottom of the fixed part there is a threaded hole designed to provide access to the fastener 5 when assembling and disassembling the segment structure. In the working condition of the structure, the hole is tightly closed by a screw plug 6. The technical result, which is achieved by using the inventive design, is that it provides self-installation of the moving part of the segment, eliminates the leakage of lubricant from the internal cavity into the environment, improves the vibration-isolating properties of the support with the proposed segments.

Claims (2)

1. The segment of the sliding support, containing two parts: the movable, designed to absorb the load from the rotor side, and the fixed, connected to the machine body, while in the fixed part there is a cavity and a channel for supplying lubricant to it from the power source, and in the moving part there are channels for supplying lubricant to the gap between the working surface of the segment and the journal of the shaft or fifth rotor,
characterized in that the elastic element connecting the indicated parts of the segment is a thin plate of an annular shape - a membrane, fastened along the inner edge with the back surface of the movable part of the segment, while in the fastening element there is a channel for supplying lubricant from the cavity in the fixed part, into the channels of the movable part, and connected to the fixed part of the segment along the outer edge, while the membrane forms a flow chamber with the cavity. 2. The sliding support segment according to claim 1, characterized in that in the center of the bottom of the fixed part there is a threaded hole tightly closed by a screw plug, while the diameter of the hole is larger than the diameter of the fastener connecting the movable and fixed parts of the segment.

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