Turbine cylinder cat claw pressing device

Abstract

The invention provides a cat claw pressing device for a steam turbine cylinder, and aims to solve the problem that a conventional cat claw limiting device can only limit the floating amount of a cat claw and cannot apply a load in advance to prevent the cat claw from floating. For part of units, due to the fact that a cylinder module is light in weight, pipeline stress and turbine power torsion reaction force are relatively large, the safety margin of cylinder stability is low, and the risk that a cylinder cat claw floats upwards is relatively large, the risk that the cylinder cat claw floats upwards cannot be reduced by adopting a conventional cat claw limiting device. The invention relates to the technical field of steam turbines, which is characterized in that a pressing block, a belleville spring group, an adjusting shim I, an adjusting shim II and a special nut are connected with a cylinder cat claw and a bearing box through a connecting bolt, so that a downward load is applied to the cylinder cat claw on the premise of not influencing relative sliding of the cylinder cat claw and the bearing box; the safety margin of the cylinder stability is further improved, and the cylinder cat claw is prevented from floating upwards.

Description

Technical Field

[0001] The invention relates to the technical field of steam turbines, in particular to a steam turbine cylinder cat claw pressing device. Background Art

[0002] Under normal steam turbine operation, in order to ensure the stability of the cylinder during the operation of the steam turbine unit, it is necessary to check the stability of the cylinder to avoid the cat's claw of the cylinder from floating up. At the same time, in order to cope with the possible floating amount of the cat's claw under extreme working conditions, conventional cat's claw limiting devices are often used, such as Figure 1 As shown, the upward buoyancy of the claw is limited. Conventional claw limiting devices often reserve a small gap t between the limit nut or limit block and the cylinder claw to allow for relative sliding between the cylinder claw and the bearing housing. However, conventional claw limiting devices can only limit the upward buoyancy of the claw and cannot prevent the claw from floating in advance.

[0003] At the same time, for some units, due to the light weight of the cylinder module, the pipeline stress and turbine power torsional reaction force are relatively large, the safety margin of cylinder stability is low, and the risk of cylinder cat's claw floating is relatively large. It is necessary to take measures to further increase the downward load at the cat's claw to improve the stability of the cylinder and avoid the floating of the cat's claw.

[0004] To this end, it is necessary to design an updated steam turbine cylinder cat claw device that can apply a downward load to the cat claw through a butterfly spring without affecting the relative sliding between the cylinder cat claw and the bearing box, thereby compensating for the problem of insufficient downward load on the cat claw caused by the light weight of the cylinder module, further improving the safety margin of cylinder stability, and preventing the cat claw from floating up. Summary of the Invention

[0005] In order to solve the problems and defects of the above-mentioned conventional cat's claw limiting device, the present invention provides a turbine cylinder cat's claw clamping device, the purpose of which is to further improve the stability of the cylinder, prevent the cylinder cat's claw from floating, and thereby improve the reliability of the entire turbine operation.

[0006] In order to achieve the purpose of the present invention, the technical solution adopted is: A steam turbine cylinder cat's claw pressing device comprises a connecting bolt 1, a pressing block 2, a disc spring group 3, an adjusting washer I 4, an adjusting washer II 5, and a special nut 6.

[0007] Among them, the cylinder cat claw clamping device is connected to the cylinder cat claw 102 and the bearing box 101, the cylinder cat claw 102 is located between the bearing box 101 and the cylinder cat claw clamping device, one end of the connecting bolt 1 is fixed to the bearing box 101, and the other end passes through the through hole of the cylinder cat claw 102 and is connected to the cat claw clamping device on the other side of the cylinder cat claw 102.

[0008] Among them, the pressure block 2 is first placed on the upper surface of the cylinder cat claw 102, and the disc spring group 3 is then placed on the upper surface 203 of the pressure block 2. The adjustment gasket I4 is placed above the disc spring group 3, and the special nut 6 is installed on the upper end of the connecting bolt 1 passing through the through hole of the cylinder cat claw 102. The adjusting gasket II5 is installed between the top of the connecting bolt 1 and the special nut 6.

[0009] Among them, the adjusting gasket I4 and the disc spring group 3 are installed in the upper cavity 601 of the groove on the inner side of the special nut 6; the disc spring group 3 applies a load to the pressure block 2, and the load is transmitted to the top of the cylinder cat claw 102 through the pressure block 2, applying a downward load to the cylinder cat claw 102. By adjusting the selection of the disc spring, the stiffness of the disc spring is changed, and the total stiffness of the disc spring group 3 is changed by adjusting the overlapping number of disc springs. By changing the thickness of the adjusting gasket I4, the deformation of the disc spring group 3 is changed. The combined adjustment of the above three methods can adjust the total load of the spring group 3 to the required range.

[0010] The boss 201 above the pressing block 2 is placed in the lower cavity 602 of the groove inside the special nut 6, thereby limiting the pressing block 2 in the horizontal direction.

[0011] Preferably, the disc spring assembly 3 is made of one or more of alloy spring steel, stainless steel, and high-temperature alloy.

[0012] Among them, the preferred alloy spring steel is 50CrVA; the preferred stainless steel is 301 stainless steel; and the preferred high-temperature alloy is Inconel718.

[0013] The disc spring group 3 is preferably in a stacked form.

[0014] Preferably, a gap t is reserved between the special nut 6 and the step surface 202 of the pressing block 2 , and a gap j is reserved between the special nut 6 and the upper table surface 203 of the pressing block 2 .

[0015] Preferably, the thickness of gasket II5 is adjusted to adjust the width of the reserved gap t, that is, by adjusting the thickness of gasket II5, it can be ensured that when the special nut 6 is tightened, the reserved gap t between the special nut 6 and the step surface 202 of the pressing block 2, and the reserved gap j between the special nut 6 and the upper table surface 203 of the pressing block 2 are greater than the reserved gap t.

[0016] Due to the existence of the reserved gap t and the reserved gap j, the horizontal relative displacement between the pressure block 2 and the cylinder cat claw 102 will not hinder the horizontal relative movement between the cylinder cat claw 102 and the cat claw pressing device and the bearing box 101, and therefore will not affect the thermal expansion of the cylinder cat claw 102.

[0017] The above technical solution has the following beneficial effects: In the cylinder cat claw clamping device, a butterfly spring is used to apply a downward load to the cat claw. The size of the load can be adjusted by selecting the butterfly spring and adjusting the gasket above the butterfly spring, thereby further increasing the downward load of the cylinder cat claw, improving the safety margin of the cylinder stability, and preventing the cat claw from floating up. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of a conventional cat claw restraint device in the prior art; Figure 2 It is a schematic diagram of the connection structure between the cylinder cat claw pressing device, the cylinder cat claw and the bearing box; Figure 3 This is a structural diagram of the cylinder cat claw pressing device; Figure 4 This is a top view schematic diagram of the cylinder cat claw pressing device structure; Figure 5 It is a schematic diagram of the three-dimensional structure of the briquette; Figure 6 Schematic diagram of the cross section of the briquette; Figure 7 This is a schematic diagram of the three-dimensional structure of a special nut; Figure 8 This is a schematic diagram of the cross section of a special nut; Among them, connecting bolt 1, pressure block 2, disc spring group 3, adjusting gasket I4, adjusting gasket II5, special nut 6, bearing box 101, cylinder cat claw 102, groove upper cavity 601, groove lower cavity 602, boss 201, step surface 202, upper table surface 203. DETAILED DESCRIPTION

[0019] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0020] Example 1 A steam turbine cylinder cat claw pressing device, the cylinder cat claw pressing device B is composed of a connecting bolt 1, a pressure block 2, a disc spring group 3, an adjusting washer I 4, an adjusting washer II 5, and a special nut 6. Figure 2 As shown, the cylinder cat claw clamping device B is connected to the cylinder cat claw 102 and the bearing box 101. The cylinder cat claw 102 is located between the bearing box 101 and the cylinder cat claw clamping device B. One end of the connecting bolt 1 is fixed to the bearing box 101, and the other end passes through the through hole of the cylinder cat claw 102 and is connected to the pressure block 2, disc spring group 3, adjustment gasket I 4, adjustment gasket II 5, and special nut 6 of the cat claw clamping device B on the other side of the cylinder cat claw 102.

[0021] In this embodiment, if Figure 4As shown, the special nut 6 is installed on the upper end of the connecting bolt 1, and the adjusting washer II5 is installed between the top of the connecting bolt 1 and the special nut 6. The thickness of the adjusting washer II5 is 10 mm. When the special nut 6 is tightened, the reserved gap t between the special nut 6 and the stepped surface 202 of the pressure block 2 is 0.15-0.18 mm, and the reserved gap j between the special nut 6 and the upper table surface 203 of the pressure block 2 is 3 mm. At this time, the reserved gap j> the reserved gap t.

[0022] The adjusting gasket Ⅰ 4 and the disc spring group 3 are installed in the groove inside the special nut 6, and the disc spring group 3 applies a load to the pressure block 2. The load is transmitted to the top of the cylinder cat claw 102 through the pressure block 2, applying a downward load to the cylinder cat claw 102.

[0023] In this embodiment, the disc spring assembly is made of 50CrVA; nine sets are stacked together; and the thickness of the adjustment spacer 14 is 8.6 mm. By combining these three methods, the total load of the disc spring assembly 3 is adjusted to 45 kN, and the reaction force at the cat's paw support is adjusted from -163.2 kN to -118.2 kN, meeting the cylinder stability requirements.

[0024] The boss 201 above the pressure block 2 fits within the groove below the special nut 6, thereby limiting the horizontal position of the pressure block 2. At the same time, due to the presence of the reserved gaps t and j, the pressure block 2 and the cylinder claw 102 can undergo horizontal relative displacement without hindering the horizontal relative movement between the cylinder claw 102, the claw clamping device B, and the bearing housing 101, thereby not affecting the thermal expansion of the cylinder claw 102.

[0025] It can be seen from this embodiment that the present invention, through the provision of the cylinder cat claw clamping device, can apply a downward load to the cylinder cat claw without affecting the relative sliding of the cylinder cat claw and the bearing box, thereby further improving the safety margin of the cylinder stability and preventing the cylinder cat claw from floating.

[0026] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A steam turbine cylinder cat claw pressing device, characterized in that: It includes connecting bolts (1), pressure blocks (2), disc spring sets (3), adjusting washers I (4), adjusting washers II (5), and special nuts (6); One end of the connecting bolt (1) is fixed to the bearing box (101), and the other end passes through the through hole of the cylinder cat claw (102) and is connected to the pressure block (2), the disc spring group (3), the adjusting gasket I (4), the adjusting gasket II (5), and the special nut (6); A pressure block (2) is first placed on the upper surface of the cylinder cat claw (102), a disc spring group (3) is placed on the upper surface (203) of the pressure block (2), an adjustment gasket I (4) is placed above the disc spring group (3), the special nut (6) is installed on the upper end of the connecting bolt (1) passing through the through hole of the cylinder cat claw (102), and the adjustment gasket II (5) is installed between the top of the connecting bolt (1) and the special nut (6); The adjusting washer I (4) and the disc spring assembly (3) are installed in the groove upper cavity (601) on the inner side of the special nut (6); The boss (201) above the pressing block (2) is placed in the lower cavity (602) of the groove inside the special nut (6).

2. The steam turbine cylinder cat claw pressing device according to claim 1, characterized in that: The disc spring group (3) is made of one or more of alloy spring steel, stainless steel, and high-temperature alloy.

3. The steam turbine cylinder cat claw pressing device according to claim 2, characterized in that: The alloy spring steel is 50CrVA.

4. The steam turbine cylinder cat claw pressing device according to claim 2, characterized in that: The stainless steel is 301 stainless steel.

5. The steam turbine cylinder cat claw pressing device according to claim 2, characterized in that: The high temperature alloy is Inconel718.

6. The steam turbine cylinder cat claw pressing device according to claim 1, characterized in that: The disc spring group (3) is in a stacked manner.

7. The steam turbine cylinder cat claw pressing device according to claim 1, characterized in that: The thickness of the adjusting gasket I (4) adjusts the deformation of the butterfly spring group 3.

8. The steam turbine cylinder cat claw pressing device according to claim 1, characterized in that: A reserved gap t is provided between the special nut (6) and the stepped surface (202) of the pressing block (2), and a reserved gap j is provided between the special nut (6) and the upper table surface (203) of the pressing block (2).

9. The steam turbine cylinder cat claw pressing device according to claim 1, characterized in that: The thickness of the adjusting gasket II (5) is adjusted to adjust the width of the reserved gap t.

10. The steam turbine cylinder cat claw pressing device according to claim 1, characterized in that: The reserved gap j>the reserved gap t.

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