Arrangement structure and method for thrust bearing test thrust pad of large hydroelectric generating set

Abstract

The invention discloses an arrangement structure and method for a thrust bearing test thrust pad of a large hydroelectric generating set. The arrangement structure comprises a thrust support, thrust pads with the same size as a real machine are arranged on the thrust support at intervals in the circumferential direction, and the outer diameter of each thrust pad is larger than that of the thrust support. The small head of the thrust pad is arranged towards the axis of the thrust bracket, and the thrust pad is arranged in the plane projection range of the thrust bracket; the thrust pad is fixed on the thrust bracket through a fixing piece; the number of the thrust pads is smaller than that of a real machine, and the number of the thrust pads is at least three. The distance between the thrust pad and the axis of the thrust support is smaller than the distance between the thrust pad and the axis of the thrust support. The arrangement method comprises the following steps that S1, thrust pads are horizontally placed on a thrust support installation plane, the small ends of the thrust pads face inwards, and the large ends of the thrust pads face outwards and are centripetally and circumferentially distributed; s2, the radial position of the thrust pad is adjusted, so that the thrust pad is located in the horizontal projection range of the thrust support; and S3, after the position of the thrust pad is determined, the thrust pad is assembled and fixed to the thrust support.

Description

Technical Field

[0001] The invention relates to the technical field of thrust bearing testing, in particular to an arrangement structure and method of a thrust bush for a thrust bearing test of a large-scale hydroelectric generator set. Background Art

[0002] Thrust bearings are the core components of hydropower units. In order to ensure the safety and reliability of thrust bearings, it is necessary to carry out thrust bearing test verification. By simulating the operating conditions of the real machine, the performance and safety margin of the thrust bearing design can be verified. Thrust bearing tests usually must meet two basic conditions: having the same unit specific pressure P and average operating linear speed v as the real machine. At present, it is mainly divided into reduced-scale tests and thrust bearing tests with 1:1 real machine bearing pad size, both of which can meet the above two conditions. Under the same circumstances, the 1:1 real machine thrust pad test effect is more convincing.

[0003] However, the construction of a bearing test bench needs to consider economic efficiency. Once built, it is difficult to change its test parameters according to the size of the bearing. First, the size of the test bench limits the size of the test bearing; second, the loading and dragging capacity of the test bench limits the choice of bearing test design; third, conducting a 1:1 thrust pad test requires a larger size and greater loading and dragging capacity, which means that the manufacturing cost of the test bench is higher from an economic perspective.

[0004] Therefore, if the outer diameter of the thrust bearing of the real machine is smaller than the outer diameter of the thrust bracket, and the loading and dragging capacity of the thrust bearing test bench meet the test requirements, the thrust bearing of the power station can be designed according to the size of the thrust bearing, and the 1:1 thrust bearing test arrangement can be directly carried out according to the operation of the real machine. Lubricating oil is injected into the oil tank shell, and the thrust bearing is immersed in the lubricating oil contained in the oil tank shell.

[0005] For the case where the outer diameter of the actual bearing is larger than the bearing test installation platform, such as Figure 7 As shown in the figure, the thrust pad installation size is larger than the outer diameter of the thrust bracket and the oil tank housing, so it cannot be installed in the test bench for testing. Usually, the only way is to design the bearing pad with a smaller size and conduct a bearing test with a reduced ratio, such as Figure 8 shown. Summary of the invention

[0006] The object of the present invention is to provide a structure and method for arranging thrust bearing pads for thrust bearing tests of large hydropower units in response to the above-mentioned problems. In the case where the outer diameter of the real machine bearing is larger than the bearing test mounting platform, a 1:1 real machine bearing arrangement of the large-size thrust pad is completed on the thrust bracket mounting plane, thereby ensuring the direct relevance and accuracy of the test results.

[0007] The technical solution adopted by the present invention is as follows:

[0008] A thrust washer arrangement structure for thrust bearing testing of a large hydroelectric unit comprises a thrust bracket, on which thrust washers having the same size as that of a real unit are arranged at intervals along the circumferential direction, and the outer diameter of the thrust washers is larger than the outer diameter of the thrust bracket; the small head of the thrust washer is arranged toward the axis of the thrust bracket, and the thrust washer is arranged within the plane projection range of the thrust bracket; the thrust washer is fixed to the thrust bracket by a fixing member; the number of the thrust washers is less than that of the real unit and includes at least 3 pieces; the distance between the thrust washer and the axis of the thrust bracket is smaller than the distance between the thrust washer and its own axis.

[0009] Optionally, each thrust washer is provided with spacer blocks on both circumferential sides, and the spacer blocks are assembled on the thrust bracket by countersunk screws.

[0010] Optionally, the length of the spacer block is equal to the length of the side of the thrust washer.

[0011] Optionally, a spring and a support shoe are further provided between the thrust shoe and the thrust bracket, and the thrust shoe, the support shoe, the spring and the thrust bracket are arranged in sequence from top to bottom.

[0012] Optionally, the thrust bracket is provided with a plurality of inner diameter limiting pins, and the plurality of inner diameter limiting pins are respectively arranged on the radial inner sides of different thrust washers.

[0013] Optionally, the thrust bearing and the support bearing are commonly connected to an outer side with an outer diameter hook plate assembly; a removable outer diameter limit finger assembly is provided on the radial outer side of the spacer block, one end of the outer diameter limit finger assembly is fixed on the spacer block, and the other end of the outer diameter limit finger assembly extends circumferentially beyond the spacer block and is provided on the radial outer side of the support bearing.

[0014] A mirror plate is also provided above the thrust washer.

[0015] A method for arranging thrust bearings for a large hydroelectric unit thrust bearing test comprises the following steps:

[0016] S1. Place thrust washers with the same size as the real machine horizontally on the thrust bracket installation plane, with the small end of the thrust washers facing inwards and the large end facing outwards, evenly distributed around the circumference;

[0017] S2. Adjust the radial position of the thrust washer so that the thrust washer is within the horizontal projection range of the thrust bracket;

[0018] S3. After the thrust washer position is determined, assemble and fix the thrust washer on the thrust bracket.

[0019] Optionally, S3 comprises the following steps:

[0020] S31. After the thrust washer position is determined, the positions of two spacer blocks are determined at the oil inlet and outlet sides of the thrust washer, and the positions of the inner diameter limit pins are determined at the inner diameter of the thrust washer;

[0021] S32. Process threaded holes on the thrust bracket installation plane, install inner diameter limit pins and countersunk screws, limit the movement of the thrust washer toward the inner diameter through the inner diameter limit pins, and install and fix two spacer blocks on both sides of the thrust washer through the countersunk screws;

[0022] S33. On the thrust support mounting plane, between two fixed spacer blocks, stack the spring, support pad and thrust pad one by one;

[0023] S34. Install the outer diameter hook plate assembly on the outside of the thrust bearing and the support bearing, and install the outer diameter limit finger assembly on the outer diameter of the spacer block.

[0024] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0025] The present invention provides a layout structure and method for thrust bearing test of a large hydroelectric unit. By reducing the total number of test bearing blocks and adjusting the layout position of the test bearing bearing, a 1:1 real machine bearing layout of a large-sized thrust bearing is completed on the thrust bracket installation plane. The method uses structures such as double-sided spacer blocks, inner diameter limit pins, outer diameter hook plate assemblies, and outer diameter limit finger assemblies to anchor the bearing position, solving the problems faced by the 1:1 real machine bearing layout of large-sized thrust bearings. By increasing the test speed to achieve the same linear speed as the real machine, reducing the total axial load to achieve the same bearing surface pressure as the real machine, ensuring that the key test condition data (bearing surface pressure and average linear speed) consistent with the real machine remain unchanged, so that the PV value remains unchanged, and a test result of 1:1 with the real machine is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0027] Figure 1 It is a schematic diagram of the layout structure of this scheme.

[0028] Figure 2 It is a schematic diagram of the structure on the radial inner side.

[0029] Figure 3 yes Figure 2 Cross-sectional view at point A.

[0030] Figure 4 It is a schematic diagram of the structure on the radial outer side.

[0031] Figure 5 yes Figure 4 Cross-sectional view at point B.

[0032] Figure 6 yes Figure 4 Cross-sectional view at point C.

[0033] Figure 7It is a structural schematic diagram of a bearing test installation platform in which the outer diameter of a real machine bearing in the background technology is larger than that of the bearing test installation platform.

[0034] Figure 8 It is a structural schematic diagram of a reduced ratio when the outer diameter of a real machine bearing size in the background technology is larger than that of a bearing test mounting platform.

[0035] Markings in the figure: 1-thrust bracket, 2-thrust washer, 3-spacer block, 4-countsunk screw, 5-spring, 6-support washer, 7-inner diameter limit pin, 8-outer diameter hook plate assembly, 9-outer diameter limit finger assembly, 10-mirror plate. DETAILED DESCRIPTION

[0036] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0037] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0038] Any feature disclosed in this specification, unless otherwise stated, can be replaced by other equivalent or alternative features with similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0039] A layout structure of thrust bearing test thrust pad for large hydropower unit, such as Figure 1-6 As shown, it includes a thrust bracket 1, on which thrust washers 2 with the same size as the real machine are placed at intervals along the circumferential direction, and the outer diameter of the thrust washers 2 is larger than the outer diameter of the thrust bracket 1; the small head of the thrust washers 2 is arranged toward the axis of the thrust bracket 1, and the thrust washers 2 are arranged within the plane projection range of the thrust bracket 1; the thrust washers 2 are fixed to the thrust bracket 1 by fixing parts; the number of the thrust washers 2 is less than that of the real machine and includes at least 3 pieces; the distance between the thrust washers 2 and the axis of the thrust bracket 1 is smaller than the distance between the thrust washers 2 and its own axis.

[0040] In this solution, when the outer diameter of the thrust washer 2 is larger than the outer diameter of the thrust bracket 1, if the axis of the thrust bracket 1 is aligned with the axis of the thrust washer 2, the outer diameter of the thrust washer 2 will exceed the thrust bracket 1. Therefore, by moving the thrust washer 2 radially inward, the thrust washer 2 can be located within the plane projection range of the thrust bracket 1 without exceeding the thrust bracket 1. At this time, the thrust bracket 1 cannot accommodate the original number of thrust washer 2, and the total number of the washer blocks is reduced, so that there is a gap between the thrust washer 2 instead of being close together, reducing the occupied area of ​​the washer blocks, and the installed thrust washer 2 can be placed within the horizontal projection range of the thrust bracket 1 to adapt to the size of the test bench. Specifically, after the thrust washer 2 is installed in the test, the specified lubricating oil is added, and the lubrication system is started to ensure that the lubricating oil can smoothly reach the contact surface between the thrust washer 2 and the thrust bearing. Then gradually apply thrust to the thrust washer 2 to simulate the load conditions in actual work. The loading can be static or dynamic to simulate different working conditions. During the loading process, the temperature, pressure, vibration and other parameters of the thrust pad 2 and the thrust bearing are monitored. The collected data is analyzed to evaluate the load-bearing capacity, lubrication performance, wear and tear of the thrust pad 2 and the thrust bearing. Therefore, as long as the thrust pad 2 can support the upper component to slide, the test can be realized, although the number of pads is reduced and the force carried by each pad increases. However, the loading force can be controlled during the test. After reducing the loading force, the load of each pad can be consistent with the test requirements. By fixing the thrust pad 2 on the thrust bracket 1, it can be ensured that the load from the runner and the main shaft can be effectively transferred to the thrust bearing, and the fixing and supporting conditions in actual work can be simulated to ensure the authenticity and reliability of the test results. At the same time, since there is a spacing between the thrust pads 2 in this scheme, fixing the thrust pads 2 can maintain the stability of the test structure and prevent the displacement of the thrust pads 2 due to vibration or other external forces during the test. The thrust pads 2 include at least 3 pieces. Since all the thrust pads 2 tested have the same size specifications, they are distributed radially around the circumference. Simplifying the thrust pads 2 into points, three points form a plane, which is sufficient to support the mirror plate 10 in a dynamic situation. Therefore, at least three thrust pads 2 are required. If there are two, they must be distributed at 180 degrees, and it is not easy to find balance on the horizontal plane. Among them, the thrust pads 2 are evenly distributed along the circumference.

[0041] As another specific implementation, each of the thrust pads 2 is provided with spacer blocks 3 on both sides of the circumference, and the spacer blocks 3 are assembled on the thrust bracket 1 by countersunk screws 4. The spacer blocks 3 are used to accurately locate the position of each thrust pad 2 on the thrust bracket 1, block the side of the thrust pad 2, and prevent the thrust pad 2 from being carried away by the rotating mirror plate along the circumferential direction and moving laterally.

[0042] As another specific embodiment, the length of the spacer block 3 is equal to the side length of the thrust washer 2. The spacer block 3 is equal to the side length of the thrust washer 2, which can ensure that the pressure is evenly distributed over the entire side length and avoid stress concentration at the edge of the thrust washer 2. The spacer block 3 can provide a complete support surface so that the thrust washer 2 is supported over the entire side, thereby improving the stability and load-bearing capacity of the thrust washer 2. This solution is only preferred. In actual settings, the length of the spacer block 3 can also be slightly longer than the side length of the thrust washer 2.

[0043] As another specific embodiment, a spring 5 and a support bearing 6 are further provided between the thrust bearing 2 and the thrust support 1, and the thrust bearing 2, the support bearing 6, the spring 5 and the thrust support 1 are arranged in order from top to bottom. The spring 5 is located between the support bearing 6 and the thrust bearing 2, and provides a pre-pressure for the thrust bearing 2. This pre-pressure ensures that a certain contact pressure is maintained between the thrust bearing 2 and the thrust plate, which is an important factor in ensuring the normal operation of the bearing. In addition, the spring 5 can play a certain shock-absorbing role, absorb and buffer the vibration caused by rotor imbalance or external impact, and protect the thrust bearing 2 and the thrust plate from damage. The support bearing 6 supports the thrust bearing 2 and transmits the radial load from the thrust bearing 2 to the thrust support 1.

[0044] As another specific implementation, the thrust support 1 is provided with a plurality of inner diameter limiting pins 7, and the plurality of inner diameter limiting pins 7 are respectively arranged on the radial inner sides of different thrust pads 2. Specifically, a limiting groove matching the inner diameter limiting pin 7 is provided on the radial inner side of the thrust pad 2, and the limiting groove and the inner diameter limiting pin 7 can ensure that each thrust pad 2 is accurately positioned on the thrust support 1, thereby preventing the thrust pad 2 from axial or radial displacement due to vibration or the like during operation.

[0045] As another specific embodiment, the thrust bearing 2 and the support bearing 6 are connected to an outer side thereof with an outer diameter hook plate assembly 8; the radial outer side of the spacer block 3 is provided with a detachable outer diameter limit finger assembly 9, one end of the outer diameter limit finger assembly 9 is fixed to the spacer block 3, and the other end of the outer diameter limit finger assembly 9 extends circumferentially beyond the spacer block 3 and is arranged radially outside the support bearing 6. The outer diameter hook plate assembly 8 connects the thrust bearing 2 and the support bearing 6 as a whole, preventing the thrust bearing 2 from axially offset under the action of axial force, thereby increasing the overall structural strength of the thrust bearing 2. The outer diameter limit finger assembly 9 can limit the radial position of the support bearing 6, preventing them from radially moving due to vibration or axial force during operation, thereby maintaining the stability and accuracy of the bearing assembly. The detachable outer diameter limit finger assembly 9 makes the assembly and disassembly of the thrust bearing 2 and the support bearing 6 more convenient. By fixing one end of the outer diameter limit finger assembly 9 on the spacer block 3, the spacer block 3 also provides support for the outer diameter limit finger assembly 9, which can simplify the structure of the fixing part, reduce the number of components, and make the structure of the entire thrust bearing system more concise.

[0046] As another specific embodiment, a mirror plate 10 is further provided above the thrust washer 2. The main function of the mirror plate 10 is to support the main shaft of the turbine and transmit the axial force to the thrust washer 2. The mirror plate 10 in the test is used to simulate the working conditions of the thrust washer 2 in an actual hydropower unit. In the test, the mirror plate 10 ensures that the applied load is evenly distributed over the entire surface of the thrust washer 2, which helps to evaluate the bearing capacity of the thrust washer 2 and the uniformity of the load distribution.

[0047] A method for arranging a thrust bearing 2 for a large hydroelectric unit thrust bearing test comprises the following steps:

[0048] S1. Place thrust washers 2 horizontally on the installation plane of thrust support 1, with the small end of thrust washers 2 facing inwards and the large end facing outwards, evenly distributed around the centripetal circle;

[0049] S2. Adjust the radial position of the thrust washer 2 so that the thrust washer 2 is located within the horizontal projection range of the thrust support 1;

[0050] S3. After the position of the thrust washer 2 is determined, the thrust washer 2 is assembled and fixed on the thrust bracket 1.

[0051] As another specific implementation, the S3 comprises the following steps:

[0052] S31, after the position of the thrust washer 2 is determined, the positions of two spacer blocks 3 are determined at the oil inlet and outlet sides of the thrust washer 2, and the position of the inner diameter limit pin 7 is determined at the inner diameter of the thrust washer 2;

[0053] S32, machining threaded holes on the thrust bracket 1 installation plane, installing inner diameter limiting nails 7 and countersunk screws 4, limiting the movement of the thrust washer 2 toward the inner diameter through the inner diameter limiting nails 7, and fixing the two spacer blocks 3 on both sides of the thrust washer 2 through the countersunk screws 4;

[0054] S33, on the installation plane of the thrust support 1, between the two fixed spacer blocks 3, stack the spring 5, the support pad 6 and the thrust pad 2 one by one;

[0055] S34, install the outer diameter hook plate assembly 8 on the outer sides of the thrust washer 2 and the support washer 6, and install the outer diameter limit finger assembly 9 on the outer diameter of the spacer block 3.

[0056] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A layout structure of thrust pads for thrust bearing tests of large hydropower units, characterized by: The invention comprises a thrust support (1), on which thrust washers (2) of the same size as the real machine are arranged at intervals along the circumferential direction, and the outer diameter of the thrust washers (2) is larger than the outer diameter of the thrust support (1); the small head of the thrust washers (2) is arranged toward the axis of the thrust support (1), and the thrust washers (2) are arranged within the plane projection range of the thrust support (1); the thrust washers (2) are fixed to the thrust support (1) by fixing parts; the number of the thrust washers (2) is less than that of the real machine and includes at least three pieces; the distance between the thrust washers (2) and the axis of the thrust support (1) is smaller than the distance between the thrust washers (2) and its own axis.

2. The arrangement structure of the thrust pad for the thrust bearing test of a large hydroelectric unit according to claim 1 is characterized in that: Each thrust washer (2) is provided with a spacer block (3) on both sides of the circumference, and the spacer block (3) is assembled on the thrust bracket (1) by means of a countersunk screw (4).

3. The arrangement structure of the thrust pad for the thrust bearing test of a large hydroelectric unit according to claim 2, characterized in that: The length of the spacer block (3) is equal to the length of the side of the thrust washer (2).

4. The arrangement structure of the thrust pad for the thrust bearing test of a large-scale hydroelectric unit according to claim 1 is characterized in that: A spring (5) and a support bearing (6) are also provided between the thrust bearing (2) and the thrust support (1); the thrust bearing (2), the support bearing (6), the spring (5) and the thrust support (1) are arranged in sequence from top to bottom.

5. The arrangement structure of the thrust pad for the thrust bearing test of a large-scale hydroelectric unit according to claim 1 is characterized in that: The thrust bracket (1) is provided with a plurality of inner diameter limiting pins (7), and the plurality of inner diameter limiting pins (7) are respectively arranged on the radial inner sides of different thrust washers (2).

6. The arrangement structure of the thrust pad for the thrust bearing test of a large hydroelectric unit as claimed in claim 2 is characterized by: The thrust washer (2) and the support washer (6) are connected to an outer side thereof with an outer diameter hook plate assembly (8); a detachable outer diameter limit finger assembly (9) is provided on the radial outer side of the spacer block (3); one end of the outer diameter limit finger assembly (9) is fixed on the spacer block (3), and the other end of the outer diameter limit finger assembly (9) extends circumferentially beyond the spacer block (3) and is provided on the radial outer side of the support washer (6).

7. The arrangement structure of the thrust pad for the thrust bearing test of a large-scale hydroelectric generator set as claimed in claim 1 is characterized by: A mirror plate (10) is also provided above the thrust washer (2).

8. A method for arranging thrust pads for thrust bearing tests of large hydroelectric units, characterized in that: The following steps are involved: S1. Place thrust washers (2) horizontally on the mounting plane of the thrust support (1), with the small ends of the thrust washers (2) facing inwards and the large ends facing outwards, evenly distributed around the circumference; S2. Adjust the radial position of the thrust washer (2) so that the thrust washer (2) is located within the horizontal projection range of the thrust support (1); S3. After the position of the thrust washer (2) is determined, the thrust washer (2) is assembled and fixed on the thrust bracket (1).

9. The method for arranging thrust pads for thrust bearing tests of large hydroelectric generator sets as claimed in claim 8, characterized in that: The S3 comprises the following steps: S31, after the position of the thrust washer (2) is determined, the positions of two spacer blocks (3) are determined at the oil inlet and outlet sides of the thrust washer (2), and the position of the inner diameter limit pin (7) is determined at the inner diameter of the thrust washer (2); S32, machining a threaded hole on the installation plane of the thrust bracket (1), installing an inner diameter limiting pin (7) and a countersunk screw (4), limiting the movement of the thrust washer (2) toward the inner diameter through the inner diameter limiting pin (7), and installing and fixing two spacer blocks (3) on both sides of the thrust washer (2) through the countersunk screw (4); S33, on the installation plane of the thrust support (1), between two fixed spacer blocks (3), stack the spring (5), the support pad (6) and the thrust pad (2) one by one; S34, installing an outer diameter hook plate assembly (8) on the outside of the thrust washer (2) and the support washer (6), and installing an outer diameter limit finger assembly (9) on the outer diameter of the spacer block (3).

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