A vertical generator thrust bearing fastening structure and determination method

Abstract

The present invention provides a vertical generator thrust bearing fastening structure, which includes a thrust bearing, a bearing support block, a thrust head, a spring bundle, a bearing seat, and a hexagon socket bolt; the lower end of the spring bundle is fixed on the bearing seat, the thrust bearing is pressed on the spring bundle, the thrust head is pressed on the thrust bearing, and a bearing support block is arranged between two adjacent thrust bearings, and the bearing support block is fixed to the bearing seat via a hexagon socket bolt. The bearing support block provided by the present invention can not only limit the tangential displacement of the thrust bearing, but also limit the radial displacement of the thrust bearing, and the shear force on the fixing bolts of the bearing support block is also small; the thrust bearing does not adopt bolts, pins and other fixing measures, and the thrust bearing does not need to lift the thrust head of the generator to disassemble the thrust bearing, and the thrust bearing can be pulled out by removing the bearing support block on one side, which is convenient for installation and disassembly and will not cause damage to the thrust bearing; the structure of the present invention is simple, and the components are easy to produce and process.

Description

Technical Field

[0001] The invention belongs to the technical field of generators, and in particular relates to a vertical generator thrust bearing fastening structure and a determination method. Background Art

[0002] Large hydroelectric power plants widely use vertical generators. The thrust pads of the generators are the contact surface between the rotating part and the fixed part of the generators. The thrust pads bear all the gravity of the rotating part of the vertical generators. When the generator is running, since the thrust head is in a rotating state, the thrust pads will receive radial centrifugal and tangential dynamic friction. In the past, since the radial centrifugal friction was not large, rectangular support blocks were usually set between the thrust pads to prevent the thrust pads from tangential displacement. With the continuous increase in the speed and capacity of the generators, some units have experienced radial displacement of the thrust pads when the generators escape in accidents. The generators cannot be restarted and need to be shut down for maintenance. This is because the thrust pads are only subject to friction with the support blocks during radial displacement, and the friction is smaller than the centrifugal force. Therefore, it is necessary to study an effective thrust pad fixing structure. Summary of the invention

[0003] The first object of the present invention is to provide a vertical generator thrust shoe fastening structure in view of the deficiencies in the prior art.

[0004] To this end, the above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0005] A vertical generator thrust bearing fastening structure, comprising a thrust bearing, a bearing support block, a thrust head, a spring bundle, a bearing seat, and a hexagon socket bolt;

[0006] The lower end of the spring bundle is fixed on the bearing seat, the thrust pad is pressed on the spring bundle, the thrust head is pressed on the thrust pad, and a pad support block is arranged between two adjacent thrust pads, and the pad support block is fixed to the bearing seat via a hexagon socket bolt;

[0007] n identical thrust pads and the support blocks between the pads form a ring. The inner diameter edge and outer diameter edge of a single thrust pad are both arc-shaped. The angle corresponding to the inner diameter edge is 2a greater than the angle corresponding to the outer diameter edge. The angle corresponding to the inner diameter edge of a single support block between the pads is 2a less than the angle corresponding to the outer diameter edge. The corresponding angle between the inner diameter edges of two thrust pads is also a.

[0008]

[0009] In the above formula:

[0010] n is the number of thrust bearings and bearing blocks between bearings;

[0011] F N is the total weight of the rotating part of the generator;

[0012] m is the mass of a single thrust pad;

[0013] v is the maximum instantaneous angular velocity of the generator;

[0014] μ 2 is the friction coefficient between the inter-wafer support block and the thrust pad;

[0015] R is the radius of the circle where the center of the thrust pad is located.

[0016] While adopting the above technical solutions, the present invention may also adopt or combine the following technical solutions:

[0017] As a preferred technical solution of the present invention: the upper end of the hexagon socket bolt of the tile support block is wedge-shaped, and the upper part of the bolt hole on the tile support block is inverted wedge-shaped to fit with the wedge-shaped upper end of the hexagon socket bolt.

[0018] As a preferred technical solution of the present invention: the upper end surface of the inter-wafer support block is higher than the center line of the thrust pad.

[0019] As a preferred technical solution of the present invention: the minimum shear stress F of the hexagon socket bolt at the center of the tile support block Lmin Need to meet:

[0020]

[0021] As a preferred technical solution of the present invention: there is a space between the top surface of the intermediate support block and the thrust head, and the length of the hexagon socket bolt is smaller than the distance between the top surface of the thrust washer and the top surface of the bearing seat, so as to facilitate the removal of the hexagon socket bolt.

[0022] The second object of the present invention is to provide a method for determining the fastening structure of the thrust bearing of a vertical generator in view of the deficiencies in the prior art.

[0023] To this end, the above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0024] A method for determining a fastening structure of a thrust bearing of a vertical generator, the method is used to determine the fastening structure of the thrust bearing of the vertical generator as described above, and comprises the following steps:

[0025] When a generator fails and runs away, all the weight of the generator will be concentrated on a thrust pad for a short period of time. n1 F is the support force of the thrust bearing block between bearings, f1 F is the friction force of the support block between tiles, a F is the centrifugal friction force on the thrust pad under the rotation of the thrust head, b F is the tangential friction force on the thrust pad under the rotation of the thrust head, n1 The tangential angle with the center of the thrust pad is b, and the force equation is:

[0026]

[0027] In the above formula:

[0028] F f1 is the friction force of the support block between tiles;

[0029] F n1 It is the support force of the thrust bearing pad from the inter-bearing support block;

[0030] F a It is the centrifugal friction force on the thrust pad under the rotation of the thrust head;

[0031] F b It is the tangential friction force on the thrust pad under the rotation of the thrust head;

[0032] F N is the total weight of the rotating part of the generator;

[0033] m is the mass of a single thrust pad;

[0034] v is the angular velocity of the generator at the highest transient speed;

[0035] μ 1 is the friction coefficient between the thrust head and the thrust washer;

[0036] μ 2 is the friction coefficient between the inter-wafer support block and the thrust pad;

[0037] R is the radius of the thrust bearing center of gravity;

[0038] According to the force equation (1), we can get:

[0039]

[0040] A single thrust washer is bilaterally symmetrical, so:

[0041]

[0042] thereby:

[0043]

[0044] While adopting the above technical solutions, the present invention may also adopt or combine the following technical solutions:

[0045] As a preferred technical solution of the present invention: the upper end of the hexagon socket bolt of the tile support block is wedge-shaped; the upper part of the bolt hole on the tile support block is inverted wedge-shaped, and the upper end surface of the tile support block is higher than the center line of the thrust pad; after all the thrust pads are in place, the tile support block is placed between the thrust pads, and then the hexagon socket bolts are placed one by one in the bolt holes of the tile support block and tightened. Under the force of the wedge-shaped contact surface between the hexagon socket bolt and the bolt hole of the tile support block, the upper part of the tile support block will deform and expand, so that it is pressed against the side of the thrust pad; at the highest transient speed, the force equation of the tile support block is:

[0046]

[0047] In the above formula:

[0048] F k1 For and F n1 The thrust pad on the other side acts in the opposite direction and receives the support force from the support block between the pads;

[0049] c is F k1 The angle between the tangent and the center of the tile support block;

[0050] F Lmin It is the minimum value of the shear stress of the hexagon socket bolt;

[0051] Since the inner diameter of the tile support block corresponds to an angle of a, and the outer diameter corresponds to an angle of 3a, c is approximately equal to 3a / 2;

[0052] Combining the load equations (1)-(2), we can get:

[0053]

[0054] The present invention provides a vertical generator thrust shoe fastening structure and determination method, which has the following beneficial effects compared with the prior art:

[0055] (1) The inter-tile support block provided by the present invention can not only limit the tangential displacement of the thrust shoe, but also limit the radial displacement of the thrust shoe, and the shear force on the fixing bolts of the inter-tile support block is also small;

[0056] (2) The thrust washer of the present invention is not fixed with bolts, pins or other fixing means. To remove the thrust washer, there is no need to lift the thrust head of the generator. The thrust washer can be pulled out by simply removing the support block between the tiles on one side. The installation and disassembly is convenient and will not damage the thrust washer.

[0057] (3) The vertical generator thrust bearing fastening structure provided by the present invention has a simple structure and its components are easy to produce and process. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 It is a plan view of the thrust shoe fastening structure of the vertical generator provided by the present invention.

[0059] Figure 2 for Figure 1 Middle AA section view.

[0060] Figure 3 for Figure 2 Middle BB cross-section.

[0061] Figure 4 It is a diagrammatic representation of the forces acting on the thrust bearing and the support block between bearings of the thrust bearing fastening structure of the vertical generator provided by the present invention at the maximum runaway speed of the generator.

[0062] Figure 5 for Figure 4 An enlarged image of . DETAILED DESCRIPTION

[0063] A vertical generator thrust bearing fastening structure comprises a thrust bearing, a bearing support block, a thrust head, a spring bundle, a bearing seat, and a hexagon socket bolt; the lower part of the spring bundle is fixed on the bearing seat; the thrust bearing is pressed on the spring bundle; the thrust head is pressed on the thrust bearing; a bearing support block is arranged between two adjacent thrust bearings; and the bearing support block is fixed to the bearing seat by means of the hexagon socket bolt.

[0064] n identical thrust pads and the pad support block form a ring. The inner diameter edge and outer diameter edge of a single thrust pad are both arc-shaped, and the angle corresponding to the inner diameter edge is 2a greater than the angle corresponding to the outer diameter edge. The angle corresponding to the inner diameter edge of a single pad support block is 2a less than the angle corresponding to the outer diameter edge. The corresponding angle between the inner diameter edges of two thrust pads is also a.

[0065] When a generator fails and runs away, all the weight of the generator will be concentrated on a thrust washer for a short period of time. Figure 4 shown. Figure 4 Medium, F n1 F is the support force of the thrust bearing block between bearings, f1 F is the friction force of the support block between tiles, a F is the centrifugal friction force on the thrust pad under the rotation of the thrust head; b F is the tangential friction force on the thrust pad under the rotation of the thrust head, n1 The tangential angle with the center of the thrust pad is b, and the force equation is:

[0066]

[0067] In the above formula:

[0068] F f1 is the friction force of the support block between tiles;

[0069] F n1 It is the support force of the thrust bearing pad from the inter-bearing support block;

[0070] Fa It is the centrifugal friction force on the thrust pad under the rotation of the thrust head;

[0071] F b It is the tangential friction force on the thrust pad under the rotation of the thrust head;

[0072] F N is the total weight of the rotating part of the generator;

[0073] m is the mass of a single thrust pad;

[0074] v is the angular velocity of the generator at the highest transient speed;

[0075] μ 1 is the friction coefficient between the thrust head and the thrust washer;

[0076] μ 2 is the friction coefficient between the inter-wafer support block and the thrust pad;

[0077] R is the radius of the thrust bearing center of gravity;

[0078] According to the force equation (1), we can get:

[0079]

[0080] A single thrust washer is bilaterally symmetrical, so:

[0081]

[0082] thereby:

[0083]

[0084] The upper end of the hexagon socket bolt of the tile support block is wedge-shaped; the upper part of the bolt hole of the tile support block is inverted wedge-shaped, and the upper end of the tile support block is higher than the center line of the thrust bearing. After the thrust bearing is in place, the tile support block is placed between the thrust bearings, and then the hexagon socket bolts are placed one by one into the bolt holes of the tile support block and tightened. Under the force of the wedge-shaped contact surface between the hexagon socket bolt and the bolt hole of the tile support block, the upper part of the tile support block will deform and expand, so that it is pressed against the side of the thrust bearing. At the highest transient speed, the force on the tile support block is as follows: Figure 4 As shown, the force equation is:

[0085]

[0086] In formula (2), F k1 is the support force of the other side on the tile support block, c is F k1 The angle between the center of the tile support block and the tangent line, F Lmin It is the minimum value of the shear stress of the hexagon socket bolt.

[0087] Since the inner diameter of the tile support block corresponds to an angle of a, and the outer diameter corresponds to an angle of 3a, c is approximately equal to 3a / 2.

[0088] Combining the load equations (1)-(2), we can get:

[0089]

[0090] The length l of the hexagon socket bolt is 3 to 6 cm smaller than the height h of the thrust bearing from the bearing seat. When a thrust bearing needs to be disassembled, insert the hexagon socket wrench into the hexagon socket of the hexagon socket bolt through the space between the bearing support block and the thrust head on either side of the thrust bearing, loosen the hexagon socket bolt of the bearing support block until the lower end leaves the bearing seat, pull out the bearing support block, and then pull out the thrust bearing without lifting the thrust head.

[0091] Specifically, the present invention is further described in detail with reference to the following specific examples.

[0092] The thrust bearing fastening structure of the vertical generator includes a thrust bearing 1, a bearing support block 2, a thrust head 3, a spring bundle 4, a bearing seat 5, and a hexagon socket bolt 6. The lower part of the spring bundle 4 is fixed on the bearing seat 5; the thrust bearing 1 is pressed on the spring bundle 4; the thrust head 3 is pressed on the thrust bearing 1; a bearing support block 2 is arranged between two adjacent thrust bearings 1; and the bearing support block 2 is fixed on the bearing seat 5 by means of a hexagon socket bolt 6. N Total weight of the rotating part of the generator F N is 1000kN; the mass m of a single thrust pad is 20kg;

[0093] The maximum transient angular velocity v of the generator is 600r / min=20πrad / s;

[0094] Friction coefficient μ between thrust head 3 and thrust washer 1 1 is 0.03;

[0095] Friction coefficient μ between the inter-wafer support block 2 and the thrust washer 1 2 is 0.85;

[0096] The radius R of the circle where the center of thrust pad 1 is located is 3m;

[0097] Twelve identical thrust pads 1 and twelve inter-pad support blocks 2 form a ring, and the inner diameter edge and the outer diameter edge of a single thrust pad 1 are both arc-shaped.

[0098]

[0099] The upper end of the hexagon socket bolt 6 on the tile support block 2 is wedge-shaped; the upper part of the bolt hole of the tile support block 2 is inverted wedge-shaped, and the upper end of the tile support block 2 is higher than the center line of the thrust washer 1. One of the hexagon socket bolts 6 is located in the center of the tile support block. After all the thrust washers 1 are in place, the tile support block 2 is placed between the thrust washers 1, and then the hexagon socket bolts 6 are placed one by one into the bolt holes of the tile support block 2 and tightened. Under the force of the wedge-shaped contact surface between the hexagon socket bolt 6 and the bolt hole of the tile support block 2, the upper part of the tile support block 2 will deform and expand, so that it is pressed against the side of the thrust washer 1. The minimum shear stress F of the hexagon socket bolt Lmin Need to meet:

[0100]

[0101] The length of the hexagon socket bolt 6 is 10 cm, and the height h between the thrust washer 1 and the bearing seat is 15 cm. When a thrust washer 1 needs to be disassembled, insert the hexagon socket wrench into the hexagon socket of the hexagon socket bolt 6 through the space between the inter-wafer support block 2 and the thrust head 3 on either side of the thrust washer 1, loosen the hexagon socket bolt 6 of the inter-wafer support block 2 until the lower end leaves the bearing seat 5, pull out the inter-wafer support block 2, and then pull out the thrust washer 1 without lifting the thrust head 3.

[0102] The above-mentioned specific implementation methods are used to explain the present invention and are only preferred embodiments of the present invention, rather than limiting the present invention. Any modifications, equivalent substitutions, improvements, etc. made to the present invention within the spirit of the present invention and the protection scope of the claims shall fall within the protection scope of the present invention.

Claims

1. A vertical generator thrust shoe fastening structure, characterized in that: The vertical generator thrust bearing fastening structure comprises a thrust bearing, a bearing support block, a thrust head, a spring bundle, a bearing seat, and a hexagon socket bolt; The lower end of the spring bundle is fixed on the bearing seat, the thrust pad is pressed on the spring bundle, the thrust head is pressed on the thrust pad, and a pad support block is arranged between two adjacent thrust pads, and the pad support block is fixed to the bearing seat via a hexagon socket bolt; n identical thrust pads and the support blocks between the pads form a ring. The inner diameter edge and outer diameter edge of a single thrust pad are both arc-shaped. The angle corresponding to the inner diameter edge is 2a greater than the angle corresponding to the outer diameter edge. The angle corresponding to the inner diameter edge of a single support block between the pads is 2a less than the angle corresponding to the outer diameter edge. The corresponding angle between the inner diameter edges of two thrust pads is also a. In the above formula: n is the number of thrust bearings and bearing blocks between bearings; F N is the total weight of the rotating part of the generator; m is the mass of a single thrust pad; v is the maximum instantaneous angular velocity of the generator; μ2 is the friction coefficient between the inter-wafer support block and the thrust pad; R is the radius of the circle where the center of gravity of the thrust pad is located; The upper end of the hexagon socket bolt of the tile support block is wedge-shaped, and the upper part of the bolt hole on the tile support block is inverted wedge-shaped to fit with the wedge-shaped upper end of the hexagon socket bolt.

2. The vertical generator thrust shoe fastening structure according to claim 1, characterized in that: The upper end surface of the inter-wafer support block is higher than the center line of the thrust pad.

3. The vertical generator thrust shoe fastening structure according to claim 1, characterized in that: Minimum shear stress F of the hexagon socket bolt at the center of the tile support block Lmin Need to meet: μ1 is the friction coefficient between the thrust head and the thrust washer.

4. The vertical generator thrust shoe fastening structure according to claim 1, characterized in that: There is a space between the top surface of the intermediate bearing block and the thrust head, and the length of the hexagon socket bolt is smaller than the distance between the top surface of the thrust bearing and the top surface of the bearing seat, so as to facilitate the removal of the hexagon socket bolt.

5. A method for determining a fastening structure of a thrust shoe of a vertical generator, characterized in that: The method is used to determine the vertical generator thrust shoe fastening structure as claimed in claim 1, and comprises the following steps: When a generator fails and runs away, all the weight of the generator will be concentrated on a thrust pad for a short period of time. n1 F is the support force of the thrust bearing block between bearings, f1 F is the friction force of the support block between tiles, a F is the centrifugal friction force on the thrust pad under the rotation of the thrust head, b F is the tangential friction force on the thrust pad under the rotation of the thrust head, n1 The tangential angle with the center of the thrust pad is b, and the force equation is: In the above formula: F f1 is the friction force of the support block between tiles; F n1 It is the support force of the thrust bearing pad from the inter-bearing support block; F a It is the centrifugal friction force on the thrust pad under the rotation of the thrust head; F b It is the tangential friction force on the thrust pad under the rotation of the thrust head; F N is the total weight of the rotating part of the generator; m is the mass of a single thrust pad; v is the angular velocity of the generator at the highest transient speed; μ1 is the friction coefficient between the thrust head and the thrust pad; μ2 is the friction coefficient between the inter-wafer support block and the thrust pad; R is the radius of the circle where the center of gravity of the thrust pad is located; According to the force equation (1), we can get: A single thrust washer is bilaterally symmetrical, so: thereby:

6. The method for determining the fastening structure of the thrust shoe of a vertical generator according to claim 5, characterized in that: The upper end of the hexagon socket bolt of the tile support block is wedge-shaped; the upper part of the bolt hole on the tile support block is inverted wedge-shaped, and the upper end surface of the tile support block is higher than the center line of the thrust bearing; after all thrust bearings are in place, the tile support block is placed between the thrust bearings, and then the hexagon socket bolts are placed one by one into the bolt holes of the tile support block and tightened. Under the force of the wedge-shaped contact surface between the hexagon socket bolt and the bolt hole of the tile support block, the upper part of the tile support block will deform and expand, so that it is pressed against the side of the thrust bearing; at the highest transient speed, the force equation of the tile support block is: In the above formula: F k1 For and F n1 The thrust pad on the other side acts in the opposite direction and receives the support force from the support block between the pads; c is F k1 The angle between the tangent and the center of the tile support block; F Lmin It is the minimum value of the shear stress of the hexagon socket bolt; Since the inner diameter of the tile support block corresponds to an angle of a, and the outer diameter corresponds to an angle of 3a, c is approximately equal to 3a / 2. Combining the force equations (1)-(2), we can obtain:

Images