A fragment pulling device and method for repairing a steam regulating valve of a steam turbine

Abstract

The present invention discloses a fragment pulling device and method for repairing a steam regulating valve of a steam turbine, comprising a flexible steel wire rope, a hook-shaped structure, a pulling hammer and a limiting device, wherein the front end of the flexible steel wire rope is connected to the hook-shaped structure, the pulling hammer is connected to the rear end of the flexible steel wire rope, and the limiting device is arranged at the rear end of the pulling hammer. The flexible steel wire rope of the present invention is convenient for entering the interior of the L-shaped nozzle channel and is impact-resistant, and the end of the device has a hook-shaped structure, which is convenient for hooking the regulating valve seat fragment, and the tail of the device is a pulling hammer device, through the impact of the pulling hammer, the regulating valve seat fragment in a stuck state inside the nozzle can be taken out; in the process of stretching and impacting, in order to ensure that the flexible steel wire rope does not cause damage to the nozzle channel.

Description

Technical Field

[0001] The invention belongs to the field of coal-fired power plant maintenance, and in particular relates to a fragment pulling device and method for repairing a steam regulating valve of a steam turbine. Background Art

[0002] The load of the steam turbine in a thermal power plant is generally adjusted by changing the amount of steam entering the steam turbine. Currently, the commonly used adjustment methods include throttling adjustment, nozzle adjustment and sliding pressure adjustment. The characteristic of throttling adjustment is that all steam entering the steam turbine must pass through the steam regulating valve and then flow to the first-stage nozzle. This adjustment method mainly uses the method of changing the opening of the regulating steam valve to throttle the steam amount. Due to the simple structure and low manufacturing cost of the steam regulating valve, it is widely used in units with various loads.

[0003] Since the high and medium pressure combined steam regulating valve of the steam turbine is in a harsh working environment of high temperature and high pressure of 0.12Mpa to 22.7Mpa and temperature of about 535℃ for a long time, the valve core and valve seat are easily eroded by steam flow and leak. In the future, in order to adapt to the access to renewable energy on the grid, it is necessary to improve the operating flexibility of coal-fired power plants, which not only requires the units to be able to operate at a sufficiently low load, but also requires the units to increase and decrease the load rate quickly enough. Therefore, in the process of flexible peak-shaving operation of coal-fired power plants, the regulating valve needs to perform actions frequently. In the process of frequent operation of steam valves, there have been accidents in which the regulating valve seat was broken. The broken regulating valve seat fragments pose a huge hidden danger to the safe operation of the steam turbine. The fragments not only block the nozzle, but also have the risk of falling into the cylinder and causing the blades to break.

[0004] The fragments of the regulating valve seat are stuck in the L-shaped channel of the nozzle. Conventional maintenance equipment is not only difficult to penetrate into the interior of the channel, but generally after the impact of high-speed steam, the contact with the nozzle channel is in an interference fit state. It is difficult to remove only the fragments of the regulating valve seat. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a fragment pulling device and method for repairing a steam turbine steam regulating valve. The device can firstly easily enter the L-shaped channel of the turbine nozzle, and secondly, the regulating valve seat fragments stuck in the nozzle channel can be loosened or removed by a pulling hammer device.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a fragment pulling device for repairing a steam regulating valve of a steam turbine, comprising a flexible steel wire rope, a hook-shaped structure, a pulling hammer and a limiting device, the front end of the flexible steel wire rope is connected to the hook-shaped structure, the pulling hammer is connected to the rear end of the flexible steel wire rope, and the limiting device is arranged at the rear end of the pulling hammer.

[0007] A reversing pulley is arranged in the middle of the flexible steel wire rope, and the reversing pulley is connected with a supporting frame.

[0008] The support frame is a retractable support frame.

[0009] Two hook-like structures are provided, and the two hook-like structures are hinged at the connection with the flexible steel wire rope.

[0010] The limiting device adopts a limiting block, and the limiting device is connected to the equipment or the equipment base.

[0011] The outer side of the flexible steel wire rope is covered with a fiber sheath.

[0012] Length marks are set on the flexible wire rope.

[0013] The flexible steel wire rope is also connected with an endoscope system.

[0014] Based on the method for pulling fragments by the fragment pulling device for repairing the steam regulating valve of a steam turbine described in the present invention, the front end of the flexible steel wire rope and the hook structure extend into the L-shaped nozzle channel, contact the regulating valve seat fragments, and adjust the relative position of the hook structure and the regulating valve seat fragments so that the hook structure hooks the regulating valve seat fragments, and the pulling hammer is pulled toward the rear end. The pulling hammer hits the limit device to reach a preset position, and the valve seat fragments loosen under the impact.

[0015] A reversing pulley is arranged in the middle of the flexible steel wire rope, and the reversing pulley is used to adjust the position of the flexible steel wire rope and the inner wall of the L-shaped nozzle channel, and change the direction of the flexible steel wire rope at the same time.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects:

[0017] The flexible steel wire rope described in the present invention is convenient for entering the L-shaped nozzle channel and is impact-resistant. The end of the device has a hook structure, which is convenient for hooking the regulating valve seat fragments. The tail of the device is a pulling hammer device, and the regulating valve seat fragments that are stuck in the nozzle can be removed through the impact of the pulling hammer.

[0018] Furthermore, in order to ensure that the flexible steel wire rope does not damage the inner wall and chamfer of the nozzle channel during the removal process, a reversing pulley device is provided.

[0019] Furthermore, the support frame is a retractable support frame, which helps to change the reversing pulley to adjust the position of the flexible steel wire rope in the L-shaped nozzle channel, so as to fully prevent the flexible steel wire rope from contacting the inner wall of the L-shaped nozzle channel.

[0020] Furthermore, two hook-shaped structures are provided, and the two hook-shaped structures are hinged at the connection with the flexible steel wire rope.

[0021] Furthermore, a fiber sheath is sheathed on the outer side of the flexible steel wire rope, which can further prevent the flexible steel wire rope from scratching the inner wall of the L-shaped nozzle channel.

[0022] Furthermore, a length mark is provided on the flexible steel wire rope, so as to facilitate observation of the length of the flexible steel wire rope penetrating into the L-shaped nozzle channel and to facilitate setting of each pulling distance.

[0023] Furthermore, the flexible steel wire rope is also connected with an endoscope system, which can help to simultaneously observe the situation in the L-shaped nozzle channel when starting to hook the regulating valve seat fragment 6, thereby helping to improve efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The present invention is a schematic diagram of a fragment pulling device used for repairing a steam regulating valve of a steam turbine.

[0025] In the attached drawings, 1-flexible steel wire rope, 2-hook structure, 3-reversing pulley, 4-pulling hammer, 5-limiting device, 6-adjusting valve seat fragment. DETAILED DESCRIPTION

[0026] The following is combined with Figure 1 The present invention is further described in detail with reference to the following specific embodiments.

[0027] refer to Figure 1 A fragment pulling device for repairing a steam regulating valve of a steam turbine comprises a flexible steel wire rope 1, a hook structure 2, a pulling hammer 4 and a limiting device 5. The front end of the flexible steel wire rope 1 is connected to the hook structure 2, the pulling hammer 4 is connected to the rear end of the flexible steel wire rope 1, and the limiting device 5 is arranged at the rear end of the pulling hammer 4.

[0028] A reversing pulley 3 is arranged in the middle of the flexible steel wire rope 1, and the reversing pulley 3 is connected to a supporting frame.

[0029] The support frame is a retractable support frame, which helps to change the reversing pulley 3 to adjust the position of the flexible steel wire rope 1 in the L-shaped nozzle channel, so as to fully prevent the flexible steel wire rope 1 from contacting the inner wall of the L-shaped nozzle channel.

[0030] Two hook-shaped structures 2 are provided, and the two hook-shaped structures 2 are hinged at the connection with the flexible steel wire rope 1 .

[0031] The limiting device 5 adopts a limiting block, and the limiting device 5 is connected to the equipment or the equipment base, which is convenient to use and disassemble, and does not increase more equipment.

[0032] The outer side of the flexible steel wire rope 1 is sheathed with a fiber sheath, which can further prevent the flexible steel wire rope 1 from scratching the inner wall of the L-shaped nozzle channel.

[0033] The flexible steel wire rope 1 is provided with a length mark, so as to facilitate observation of the length of the flexible steel wire rope 1 penetrating into the L-shaped nozzle channel and to facilitate setting of each pulling distance.

[0034] The flexible steel wire rope 1 is also connected with an endoscope system, which can help to simultaneously observe the situation in the L-shaped nozzle channel when it starts to hook the regulating valve seat fragment 6, which helps to improve efficiency.

[0035] Based on the method for pulling fragments by the fragment pulling device for repairing the steam regulating valve of a steam turbine described in the present invention, the front end of the flexible steel wire rope 1 and the hook structure 2 extend into the L-shaped nozzle channel and contact the regulating valve seat fragment 6. The relative position of the hook structure 2 and the regulating valve seat fragment 6 is adjusted so that the hook structure 2 hooks the regulating valve seat fragment 6, and the pulling hammer 4 is pulled toward the rear end. The pulling hammer 4 hits the limit device 5 to reach the preset position, and the valve seat fragment 6 is loosened under the impact.

[0036] A reversing pulley 3 is arranged in the middle of the flexible steel wire rope 1 , and the reversing pulley 3 is used to adjust the position of the flexible steel wire rope 1 and the inner wall of the L-shaped nozzle channel, and change the direction of the flexible steel wire rope 1 at the same time.

[0037] like Figure 1 As shown, a fragment pulling device for repairing a steam turbine steam regulating valve, wherein the steel wire rope 1 is adjusted in length and direction to facilitate penetrating into the L-shaped nozzle channel and contacting the regulating valve seat fragment 6; the head of the device is a hook-shaped structure 2, which is convenient for hooking the regulating valve seat fragment 6 during the pulling process.

[0038] The tail of the device is a pulling hammer device, including a pulling hammer 4 and a limit device 5. The pulling hammer 4 is strung on the flexible steel wire rope 1 and can slide freely. The pulling hammer 4 is pulled outward to hit the limit device 5, thereby causing the hook structure 2 to stretch outward and impact the valve seat fragment 6.

[0039] In the process of stretching and impacting, in order to ensure that the flexible steel wire rope does not cause damage to the nozzle channel, a reversing pulley device is set in the middle of the flexible steel wire rope 1. On the one hand, the device changes the pulling direction of the pulling hammer device, making it convenient to carry out the pulling operation, and on the other hand, the flexible steel wire rope does not scratch or collide with the inner wall and chamfer of the nozzle channel, so that it is not damaged during the pulling process.

[0040] The flexible steel wire rope of the endoscopic inspection device is convenient for entering the L-shaped nozzle channel, and the end of the device has a hook structure to easily hook the valve seat fragments. In addition, the tail of the device is a pulling hammer device, through the impact of the pulling hammer, the valve seat fragments in the stuck state inside the nozzle can be removed.

[0041] In order to ensure that the flexible steel wire rope does not damage the inner wall and chamfer of the nozzle channel during the removal process, a reversing pulley device is provided.

[0042] After loosening the regulating valve seat fragments using the device described in the present invention, the flexible steel wire rope 1 can be taken out, and then the taking-out device can be used to grab it using a mechanical claw connected to the flexible spring body. Of course, when grabbing, the endoscope device can also be connected to the flexible spring body for easy observation. On the one hand, the flexible spring body can smoothly enter the L-shaped nozzle channel, and on the other hand, the flexible spring body can effectively transmit torque and adjust the orientation of the mechanical claw for effective grabbing.

Claims

1. A fragment pulling device for repairing a steam regulating valve of a steam turbine, characterized in that: The invention comprises a flexible steel wire rope (1), a hook-shaped structure (2), a pulling hammer (4) and a limiting device (5), wherein the front end of the flexible steel wire rope (1) is connected to the hook-shaped structure (2), the pulling hammer (4) is connected to the rear end of the flexible steel wire rope (1), and the limiting device (5) is arranged at the rear end of the pulling hammer (4); a reversing pulley (3) is arranged in the middle of the flexible steel wire rope (1), and the reversing pulley (3) is connected to a support frame; the support frame is a retractable support frame, two hook-shaped structures (2) are arranged, and the two hook-shaped structures (2) are hinged at the connection with the flexible steel wire rope (1); a fiber sleeve is arranged on the outer side of the flexible steel wire rope (1); a length mark is arranged on the flexible steel wire rope (1), and the flexible steel wire rope (1) is also connected to an endoscope system.

2. The fragment pulling device for repairing a steam regulating valve of a steam turbine according to claim 1, characterized in that: The limiting device (5) adopts a limiting block, and the limiting device (5) is connected to the equipment or the equipment base.

3. A method for pulling out fragments based on the fragment pulling device for repairing a steam regulating valve of a steam turbine according to claim 1 or 2, characterized in that: The front end of the flexible steel wire rope (1) and the hook-shaped structure (2) extend into the interior of the L-shaped nozzle channel and contact the valve seat fragment (6). The relative position of the hook-shaped structure (2) and the valve seat fragment (6) is adjusted so that the hook-shaped structure (2) hooks the valve seat fragment (6), and the pulling hammer (4) is pulled toward the rear end. The pulling hammer (4) hits the limit device (5) to reach a preset position and is loosened under the impact of the valve seat fragment (6). A reversing pulley (3) is arranged in the middle of the flexible steel wire rope (1). The reversing pulley (3) is used to adjust the position of the flexible steel wire rope (1) and the inner wall of the L-shaped nozzle channel and change the direction of the flexible steel wire rope (1) at the same time.

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