Turbine thrust bearing supporting structure

Abstract

The utility model relates to the field of steam turbines, in particular to a steam turbine thrust bearing supporting structure which comprises a support, a spring, a pin, a connector and a bearing body, the spring and the pin are placed in the support, the connector is located above the pin, the center line of the spring is consistent with the center line of the pin and the center line of the connector, and the bearing body is arranged on the support. According to the supporting structure, the load of the thrust bearing on the structure is effectively borne, the situation that the split of the thrust bearing deviates from the horizontal plane much due to the fact that the thrust bearing body inclines due to the dead weight is avoided, the supporting position and rigidity performance of the structure are determined through accurate and reasonable calculation, and part of vibration of the bearing body can be absorbed through the springs in the supporting structure; and the stability of the thrust bearing is enhanced.

Description

Technical Field

[0001] The utility model relates to the field of steam turbines, in particular to a steam turbine thrust bearing support structure. Background Art

[0002] Due to the structural characteristics of the turbine thrust bearing, the part of the left end of the bearing body where the thrust pad is installed protrudes far out, and it is very difficult to ensure that the center plane of the thrust bearing is horizontal only by the pressure generated by the rotor on the thrust bearing radial pad. Moreover, when the turbine is uncovered and repaired, the rotor pressure will disappear, and the thrust bearing body will tilt more due to its own weight, which is not conducive to keeping the center plane of the thrust bearing horizontal. In addition, the dynamic load of the thrust bearing during operation is also more complicated. If these dynamic and static loads cannot be effectively supported, it is easy to affect the installation and use accuracy and life of the thrust bearing, and also affect the stability of the turbine unit. Utility Model Content

[0003] The utility model aims to provide a steam turbine thrust bearing support structure, which can solve the problem of maintaining the stability of the steam turbine bearing.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a turbine thrust bearing support structure, characterized in that it includes: a support, a spring, a pin, a joint, and a bearing body, the spring and the pin are placed inside the support, and the joint is located above the pin.

[0005] The center lines of the spring, the pin and the joint are aligned.

[0006] The pin is not completely in contact with the top of the support, leaving a gap of 1 to 2 mm.

[0007] The contact point between the upper end of the joint and the bearing body is not fixed.

[0008] The upper part of the joint is processed into an arc surface that matches with the bearing body.

[0009] Compared with the prior art, the beneficial effects of the utility model are:

[0010] In actual operation, the thrust bearing of the steam turbine needs to withstand the effects of a variety of complex loads, including axial thrust, radial force and torque, etc. In addition, the thrust bearing also bears the task of absorbing part of the bearing vibration. Since the steam turbine may be affected by various external interferences and internal factors during operation, the bearing will vibrate. If these vibrations are not effectively controlled, it will not only affect the stable operation of the steam turbine, but also may cause bearing damage and unit failure. Therefore, the thrust bearing needs to have good vibration absorption capacity to reduce the impact of vibration on the steam turbine. In the utility model, the pin has a margin, and the middle face of the radial bearing liner after support is repaired during assembly so that the support is in a horizontal position. The contact between the upper end of the joint and the bearing body is not fixed to ensure that when the turbine rotor is flexibly deformed during rotation, the spring support will not generate tension on the bearing body. The upper part of the joint is processed into an arc surface that matches the bearing body, increasing the contact area, changing from point contact to surface contact, and reducing stress concentration. Therefore, the utility model effectively bears the load of the thrust bearing on the structure, and also absorbs part of the bearing vibration to maintain the stability of the steam turbine bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Schematic diagram of the supporting structure.

[0012] Figure 2 Schematic diagram of the forces acting on the thrust bearing and supporting structure.

[0013] Figure 3 Simplified diagram of the forces acting on the thrust bearing and supporting structure.

[0014] In the figure: 1. support; 2. spring; 3. pin; 4. joint. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0016] See also Figure 1-2 The utility model provides a technical solution: a turbine thrust bearing support structure, characterized in that it includes: a support 1, a spring 2, a pin 3, a joint 4, and a bearing body, wherein the spring 2 and the pin 3 are placed inside the support 1, and the joint 4 is located above the pin. The center lines of the spring 2, the pin 3, and the joint 4 are consistent.

[0017] The pin 3 is not in complete contact with the top of the support 1, leaving a gap of 1 to 2 mm.

[0018] In this embodiment, it is very difficult to ensure that the center plane of the thrust bearing is horizontal only by the pressure generated by the rotor on the radial bearing bushing, but the pin 3 has a margin, which can be adjusted during assembly so that the center plane of the radial bearing bushing after support is in a horizontal position (the adjustment margin is about 1~2mm).

[0019] The contact point between the upper end of the joint and the bearing body is not fixed.

[0020] In this embodiment, due to the high-speed rotation of the rotor and the influence of the high-temperature environment, it may undergo flexural deformation. The contact between the upper end of the joint 4 and the bearing body is not fixed, which can not only effectively prevent the pulling force on the bearing body caused by the flexural deformation of the turbine rotor, but also improve the stability and durability of the turbine.

[0021] The upper part of the joint 4 is processed into an arc surface that matches with the bearing body.

[0022] In this embodiment, the upper part of the joint 4 is processed into an arc surface that matches the bearing body. By processing into the arc surface, the contact area between the joint 4 and the bearing body is greatly increased, which means that when bearing load, the pressure distributed on the contact surface will become more uniform. Compared with traditional point contact, surface contact can better disperse the pressure, thereby reducing the concentration of local stress, and can significantly reduce the wear and fatigue damage caused by stress concentration.

[0023] The contents involved in the above embodiment are described below in conjunction with a preferred embodiment.

[0024] like Figure 1 As shown, the structure includes a support 1, a spring 2, a pin 3, and a joint 4. The support 1 is fixed to the pre-cast bracket of the front bearing seat by screws to ensure that the support 1 is located directly below the bearing. The spring 2 and the pin 3 are fixed to the front bearing seat by screws. Figure 1 Place it in a fixed support, adjust the upper height of the pin 3 so that the center plane of the radial bearing bush is in a horizontal position, and the spring 2 is determined by the following steps.

[0025] The left and right position L2 of support 1 is calculated by force analysis after abstracting the thrust bearing into a cantilever beam model. It is known that F2 is the thrust bearing's own weight, and F3 is the pressure of the rotor on the thrust bearing radial pad. The support force F1 of the support structure is calculated by the force balance formula F1=F2+F3. It is known that the distance L2 from the center of gravity of the thrust bearing to the center line of the front bearing and the thrust bearing's own weight is F2. The distance L1 from the support structure to the center line of the front bearing is calculated by the moment balance formula F1*L1=F2*L2.

[0026] It is known that x2 is the working length of spring 2 after the thrust bearing and the support structure are installed. The relationship between the initial length x1 of spring 2 and the spring stiffness K can be known from the spring 2 elastic formula F1=k(x1-x2). For different standard springs, when the stiffness K is selected, the initial length x1 of spring 2 can also be determined, and spring 2 can be determined.

[0027] In actual operation, the thrust bearing of the steam turbine needs to withstand the effects of various complex loads, including axial thrust, radial force and torque, etc. In addition, the thrust bearing also bears the task of absorbing part of the bearing vibration. Since the steam turbine may be affected by various external interferences and internal factors during operation, the bearing will vibrate. If these vibrations are not effectively controlled, it will not only affect the stable operation of the steam turbine, but also may cause bearing damage and unit failure. Therefore, the thrust bearing needs to have good vibration absorption capacity to reduce the impact of vibration on the steam turbine. In the utility model, the pin 3 has a margin, and the middle face of the radial bearing liner after support is repaired during assembly so that the support is in a horizontal position. The contact between the upper end of the joint 3 and the bearing body is not fixed to ensure that when the turbine rotor is flexibly deformed during rotation, the spring support 1 will not generate tension on the bearing body. The upper part of the joint 4 is processed into an arc surface that matches the bearing body, increasing the contact area, changing from point contact to surface contact, and reducing stress concentration. Therefore, the utility model effectively bears the load of the thrust bearing on the structure, and also absorbs part of the bearing vibration to maintain the stability of the steam turbine bearing.

[0028] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprising a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0029] The specific implementation methods provided by the utility model are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the utility model. The description of the above embodiments is only used to help understand the method and core idea of ​​the utility model. At the same time, for general technicians in this field, according to the idea of ​​the utility model, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the utility model.

Claims

1. A steam turbine thrust bearing support structure, characterized in that: include: A support (1), a spring (2), a pin (3), a joint (4), and a bearing body. The spring (2) and the pin (3) are placed inside the support (1), and the joint (4) is located above the pin (3).

2. A steam turbine thrust bearing support structure according to claim 1, characterized in that: The center lines of the spring (2), the pin (3) and the joint (4) are consistent.

3. A steam turbine thrust bearing support structure according to claim 2, characterized in that: The pin (3) is not in complete contact with the top of the support (1), leaving a gap of 1 to 2 mm.

4. A steam turbine thrust bearing support structure according to claim 1, characterized in that: The contact point between the upper end of the joint (4) and the bearing body is not fixed.

5. A steam turbine thrust bearing support structure according to claim 4, characterized in that: The upper portion of the joint (4) is processed into an arc surface that matches the bearing body.

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