RU2349415C2 - Method of receiving antifrictional layer of frictional bearing - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention concerns foundry engineering field. Method includes mounting of bearing brass, its heating, babbiting and plastic deformation of antifrictional layer by deforming tool. Insert is installed on end surface. Deforming tool is brought to insert with spacing formation between them, equal to h+Δ, where h - thickness of antifrictional layer, Δ - trip of deforming tool during plastic deformation of antifrictional layer. Babbit is run to formed spacing.

EFFECT: it is achieved labour-intensiveness reduction at receiving of bearing antifrictional layer.

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Description

The invention relates to the field of engineering, and in particular to a method for producing an antifriction layer of a sliding bearing. The method can be used in the manufacture and repair of a sliding bearing. The most effective method can be used to obtain the antifriction layer of a large bearing. Large-sized bearings are widely used as part of equipment for power engineering, transport and petrochemistry as bearings for the shafts of steam turbines of thermal power plants, bearings of the main and connecting rod necks of crankshafts of ship and diesel diesel engines and diesel generators, large reciprocating compressor machines for the production of ammonia and methanol.

A known method of producing an antifriction layer of a sliding bearing by casting [1]. The babbit is poured by squeezing into the cavity between the insert and the movable matrix. In this case, the liner is oriented in space in such a way that the metal is squeezed from the bottom up with the formation of a technological tide that acts as a feeder when the babbit shrinks.

The method is characterized in that the obtained antifriction layer has porosity and heterogeneity characteristic of any product obtained by casting.

Also, the method is characterized by increased consumption of babbitt due to the presence of extended gate channels.

A known method of obtaining an antifriction layer of a sliding bearing by casting and subsequent plastic deformation [2]. During deformation, a bearing shell is used as a matrix. The method includes the operations of installing the bearing shell, pouring babbit into the bearing shell, supplying a deforming tool with redistribution of the melt in the gap between the deforming tool and the liner, taking into account the working stroke of the deforming tool, and subsequent plastic deformation.

The method due to the use of plastic deformation allows to eliminate porosity in the antifriction layer, and also to increase its structural uniformity. In addition, the babbitt consumption is reduced due to the lack of gate channels.

For the implementation of the method, as a rule, a powerful hydraulic press with large stamping space and the crosshead travel is used. The latter is due to the fact that the punch is retracted upward to a distance sufficient to fill the babbitt into the insert. Otherwise, this operation is associated with excessive laboriousness. With increasing dimensions of the bearing, the required stamping space and the stroke of the hydraulic press beam, and accordingly its power, increase, respectively [3]. It should be noted that the press power is not fully used, since the deformation of the babbitt occurs at low values of the required efforts.

Thus, the use of hydraulic press to implement the method of obtaining the antifriction layer is economically disadvantageous, especially in the conditions of repair shops.

A common disadvantage of both known methods is the need for machining the surface of the liner, which is interfaced with another liner in the finished sliding bearing. In the method [1], a technological tide emerges on this surface from one side, and the gating channels on the other. In the method [2], an excess of babbitt is squeezed onto this surface during plastic deformation.

The machining of the mating surface must be carried out carefully so as not to touch the surface of the liner, the additional processing of which is not allowed. It also leads to increased labor intensity.

The objective of the invention is to reduce the complexity and increase the efficiency of the method of obtaining an antifriction layer of a sliding bearing.

The problem is solved when the method of obtaining an antifriction layer of a sliding bearing by casting and subsequent plastic deformation, in which the bearing shell is used as a matrix, including the operations of installing the bearing shell, heating it, pouring babbit into the liner, supplying a deforming tool, plastic deformation, differs from known for the fact that the liner is installed on the end surface, after which a deforming tool is brought to it with the formation of a gap between the last and kladyshem equal to h + Δ, where h - the thickness of the sliding layer, Δ - working stroke of the tool during the plastic deformation of the antifriction layer is then carried out to fill the resulting gap babbitt and plastic deformation is carried out with the application of force in a horizontal direction.

The essence of the invention is to change the spatial orientation of the bearing shell during casting and plastic deformation of the antifriction layer. Changing the spatial orientation of the bearing shell entails a change in the sequence of operations of the method, namely, the filling of the babbitt is carried out after the supply of the deforming tool, which ensures the convenience of filling. Moreover, to create a force that is applied in the horizontal direction to effect deformation, the use of powerful equipment, such as a hydraulic press, is not required. It is possible to use a device that is structurally simple, consisting of standardized units and parts, of sufficiently low cost and power. Such a device may contain, as main components, a welded bed from a rolling profile and a hydraulic drive, used, for example, in jacks.

In addition, the excess babbitt during pouring and plastic deformation is squeezed onto the end surface of the bearing shell, allowing machining, therefore, machining is performed with much less labor than in the known method. This technique indirectly affects the improvement of bearing quality.

Thus, in comparison with the known method provides convenience, reducing the complexity and energy costs for all operations of the method in the manufacture or repair of a sliding bearing.

The invention is illustrated by drawings, where:

figure 1 shows a diagram of a method with the equipment used, side view;

figure 2 shows a diagram of a method with the equipment used, top view.

The bearing shell 1 (Fig. 1) is mounted on a fixed platform 2, rigidly connected to the bed 3. The bed is a welded structure in the form of a channel frame. The insert is fixed relative to the bed by means of adjustable stops 4, 5. A limiter 6 with a chamber 7 is installed on the end surface of the insert. Pos. 8 deforming tool. The deforming tool can be made hollow, in the form of a pipe, with stiffeners 9. The deforming tool is rigidly connected to the hydraulic actuator 10 by means of a pusher 11. Heaters are provided for heating the liner (not shown in Fig. 1). The control of the heaters is carried out by means of a thermocouple (not shown in Fig. 1). The resulting antifriction layer in figure 1 is designated 12.

Figure 2 shows a device for implementing the method with the equipment used, a top view where pos.13 shows heaters for heating the liner. Pos. 14, 15 - stops for fixing the liner.

The method is as follows.

The bearing shell 1 is mounted on a fixed platform 2, rigidly connected to the bed so that the surface of the bearing, which is mating with another bearing in the finished sliding bearing, abuts against the stops 14 and 15. On the opposite side, the bearing is pressed using adjustable stops 4 and 5 The deforming tool is brought, by means of a hydraulic actuator, to a distance h + Δ from the fill surface of the liner. Next, the insert is heated by means of heaters 13. Upon reaching the set temperature of the insert, liquid babbitt is poured into the gap between the deforming tool and the insert through the chamber 7. After pouring the babbitt, the heaters 13 are turned off, the deforming tool is set in motion by means of a hydraulic actuator, and the babbitt is deformed by Δ with the formation of an antifriction layer of a given thickness h. In this case, the excess babbitt is squeezed out into the chamber 7. After cooling, the liner with the obtained antifriction layer is removed from the device.

A specific example of the method.

In the example, babbitt composition Sn-Sb11-Сu6 (Б83), the solidification temperature of which is 237 ° С, was used as the material of the antifriction layer.

The above example does not exhaust all cases of the invention, including those associated with other dimensions of the bearing and brands of babbitt.

The sliding bearing of a steam turbine that was in operation at a thermal power station, whose liner had the following dimensions, was repaired: maximum outer diameter 620 mm, length 500 mm, average diameter of the poured surface 310 mm. As a deforming tool, a thick-walled pipe was used, reinforced inside by a stiffener. The pusher was fixed to the pipe by a threaded connection. A threaded hole was made in the pipe stiffener.

The surface of the liner was prepared for pouring: subjected to sandblasting, etching, tinning. The liner was mounted on a fixed platform, fixed by means of adjustable stops. The joints between the liner and the platform, as well as between the liner and the stops 14, 15 were sealed with a heat-resistant mass, which is an asbestos powder soaked in water. The deforming tool was brought to a distance of h + Δ = 5 + 4 = 9 mm from the fill surface of the liner. The liner was heated by electric heaters 13 to a temperature of 240 ° C. Temperature control was carried out by means of a KTHA thermocouple. Upon reaching the set temperature of the insert, babbitt having a temperature of 450 ° C was poured through the chamber 7. Next, the heaters 13 were turned off.

Upon reaching a temperature of 220 ° C, the deforming tool was set in motion by means of a hydraulic actuator and the deformation of babbitt was carried out by a value of Δ = 4 mm with the formation of an antifriction layer of a given thickness h = 5 mm. Moreover, at the final moment of deformation, excess babbitt was squeezed out into chamber 7. At the end of the deformation process, the deforming tool was removed from the insert. After the liner was completely cooled, the adjustable stops 4, 5 were loosened and the liner with the obtained antifriction layer was removed.

Information sources

1. Patent RU No. 2167738, IPC B22D 19/08, 2001

2. Patent RU No. 2295423, IPC B22D 19/08, 2007

3. Belov A.F., Rozanov B.V., Linz V.P. Die forging on hydraulic presses. M. Engineering, 1986

Claims (1)

A method of obtaining an antifriction layer of a sliding bearing by molding and subsequent plastic deformation, in which a bearing shell is used as a matrix, including installing a bearing shell, heating it, pouring babbitt and plastic deformation of the antifriction layer with a deforming tool, characterized in that the liner is mounted on the end surface, bring the deforming tool to the liner with the formation of a gap between them equal to h + Δ, where h is the thickness of the antifriction layer, Δ is the deflection working stroke the forming tool during plastic deformation of the antifriction layer, then the babbitt is poured into the formed gap and plastic deformation with the application of force in the horizontal direction.

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