Lifting device for disassembling and overhauling high-pressure valve group of steam turbine

Abstract

The lifting device comprises a supporting mechanism and a lifting mechanism, the supporting mechanism comprises two long stand columns, short stand columns, a cross beam and a sliding rail, the two long stand columns are arranged on the two sides of the front portion of a valve support respectively, and the lower ends of the long stand columns are connected with ground anchoring parts; the upper ends of the two long stand columns are correspondingly connected with the two ends of the cross beam respectively, the lower ends of the short stand columns are connected with the top face of a valve body or a valve support top extending structure, one end of the sliding rail is connected with the middle of the cross beam, and the other end of the sliding rail is connected with the upper ends of the short stand columns. The hoist crane is connected with a valve element to be disassembled through a hoisting tool and a counterweight tool. The lifting device has the advantages that the lifting device is special in structure, the valve body is used as one supporting leg, the whole building is simple and fast, the required mounting space is small, a main crane or an auxiliary crane in a steam turbine plant is not occupied in the window period of power plant maintenance, and the utilization rate of resources is obviously improved.

Description

Technical Field

[0001] The invention belongs to the technical field of auxiliary equipment for steam turbine maintenance, and in particular relates to a lifting device for disassembling and repairing a high-pressure valve group of a steam turbine. Background Art

[0002] In the steam turbine operation system, the high-pressure main steam valve group plays a vital role in the operation of the steam turbine. It controls the flow and pressure of high-pressure steam entering the steam turbine, and can be quickly and automatically closed in critical situations to cut off the main steam passage entering the steam turbine. Therefore, the working state of the high-pressure main steam valve group will directly affect the safe and stable operation and power output of the steam turbine, and then affect the power generation efficiency of the power plant. In the operation of the power plant, the inspection and maintenance of the high-pressure main steam valve group is very important, and the inspection and maintenance requirements are also increasing. The existing high-pressure main steam valve group is as shown in the attached figure. Figure 1 and 2 As shown in the figure, it consists of two groups of high-pressure regulating valves and high-pressure main steam valves, which are installed and fixed on the turbine platen through valve brackets. Each group of high-pressure valve groups is mainly composed of servo motors, actuators, valve covers, valve cores, valve seats and valve bodies. According to the inspection and maintenance strategy requirements, at least a single group of high-pressure regulating valves and valve cores of high-pressure main steam valves in the upper or lower high-pressure main steam valve group need to be disassembled and inspected.

[0003] During the regular inspection and maintenance of the steam turbine and the handling of sudden faults, it is necessary to disassemble, inspect, repair, and replace the high-pressure main steam valve group. The current steam turbine high-pressure main steam valve group has many inconveniences and limitations during the inspection and maintenance operation. It usually relies on large-scale lifting equipment (main crane / auxiliary crane) or temporary scaffolding and simple lifting devices in the factory. Large-scale lifting equipment in the factory is a scarce resource, and its scheduling and use costs are high. The temporary scaffolding and simple lifting devices have poor stability, and the weight of the lifting and maintenance of the high-pressure main steam valve is large, which poses certain safety hazards; in addition, other devices may be placed on the ground on both sides of the high-pressure main steam valve group or the space itself is small, so there is no space for the conventional structure of the lifting device to install multiple support legs on both sides. In addition, during the lifting and maintenance of the high-pressure main steam valve, whether it is large-scale lifting equipment (main crane / auxiliary crane) or temporary scaffolding and simple lifting devices, it takes a lot of time and manpower and material resources to adjust the equipment or design and build. Summary of the invention

[0004] The present invention provides a lifting device for disassembling and repairing a high-pressure valve group of a steam turbine, aiming to overcome the above-mentioned shortcomings existing in the prior art.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: a lifting device for disassembly and maintenance of a high-pressure valve group of a steam turbine, comprising a supporting mechanism and a lifting mechanism, the supporting mechanism comprising a long column and a short column arranged vertically and a horizontal beam and a slide rail arranged horizontally, the long columns are provided with two and are respectively arranged on both sides in front of the valve support, the lower end of the long column is connected to the ground anchoring part, the upper ends of the two long columns are respectively connected to the two ends of the beam, the lower end of the short column is connected to the top surface of the valve body or the top extension structure of the valve support, one end of the slide rail is connected to the middle part of the beam, and the other end is connected to the upper end of the short column, the lifting mechanism comprises a lifting hoist slidably connected to the slide rail, the lifting hoist is connected to the valve core to be disassembled through a lifting tool and a counterweight tool and keeps the valve core suspended and axially in a horizontal direction after leaving the valve body.

[0006] Based on the above technical solution, the present invention can also be improved as follows.

[0007] Furthermore, the ground anchoring portion is a pre-buried anchor provided on the ground, and the portion of the pre-buried anchor exposed from the ground is provided with a connector that cooperates with the lower end of the long column for detachable connection.

[0008] Furthermore, the crossbeam is detachably connected to the long column and the slide rail via bolts, the slide rail is detachably connected to the short column via bolts, and the lower end of the short column is detachably connected to a connecting seat provided at the top of the valve body via bolts.

[0009] Furthermore, a diagonal brace for strengthening is connected between the lower side of the cross beam and the inner side of the long column.

[0010] Furthermore, the lifting hoist is an electric hoist or a hand chain hoist.

[0011] Furthermore, the long columns, short columns and cross beams are H-shaped steels, and the slide rails are I-shaped steels.

[0012] Furthermore, the lifting tool includes an upper cross bar, a lower cross bar and connecting screws on left and right sides, wherein the upper end of the connecting screw is connected to one side of the upper cross bar, and the lower end is connected to one side of the lower cross bar.

[0013] Furthermore, a hanging plate is fixed on the top of the upper cross bar, and a hanging hole for hanging the hook of the lifting hoist is opened on the hanging plate. A hanging joint for connecting with a counterweight tool is provided at the bottom of the lower cross bar.

[0014] Furthermore, the counterweight tool includes a counterweight shaft, a fixed plate, a counterweight block and a plurality of connecting ribs. The counterweight shaft is coaxial with the fixed plate and the central axes are all in the horizontal direction. One end of the counterweight shaft is connected to the fixed plate through a plurality of connecting ribs arranged at circumferential intervals, and the other end of the counterweight shaft is connected to the counterweight block. The fixed plate is used to be detachably connected to the valve core to be disassembled by bolts. At least one of the connecting ribs is vertically arranged and has a hanging hole at the top end that cooperates with the hanging joint.

[0015] Furthermore, the counterweight block is cylindrical and can be detachably sleeved on the counterweight shaft.

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

[0017] The present invention designs a supporting mechanism with long and short columns and uses the valve body as one of the supporting legs. The erection is simple and quick, and the required installation space is small. After the lifting mechanism including the lifting hoist, lifting tools and counterweight tools are arranged on the supporting mechanism, the valve core can be smoothly disassembled and assembled; during the window period of power plant maintenance, the scarce resources (main crane or auxiliary crane) in the steam turbine plant are not occupied, which significantly improves the utilization rate of resources.

[0018] The connections of the long and short columns, slide rails and beams of the support mechanism in the present invention are all detachable, making the installation and disassembly process of the support mechanism simple and quick, greatly shortening the maintenance preparation time, improving work efficiency and saving labor costs; using high-strength materials and reasonable structural design, after strict mechanical property analysis and practical application verification, it is ensured that the lifting device has high stability and safety during use, effectively protecting the personal safety of maintenance personnel and the integrity of equipment.

[0019] The lifting tool and counterweight tool used in the present invention have unique structures and can cooperate well with the lifting hoist to realize stable lifting of the valve core. In the lifting state, the force on the valve core itself is relatively dispersed, which will not cause damage to the valve core. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The isometric view of the left high-pressure valve group (upper and lower groups) of the existing steam turbine installed in the valve bracket;

[0021] Figure 2 for Figure 1 An axonometric view of a high-pressure valve group is shown, comprising a high-pressure regulating valve and a high-pressure main steam valve (both valves have a valve body and a valve core) connected to each other.

[0022] Figure 3 An axonometric view of the support mechanism of the lifting device for disassembly and maintenance of the steam turbine high-pressure valve group provided by the present invention;

[0023] Figure 4 An axonometric view of a lifting tool in a lifting mechanism of a lifting device for disassembly and maintenance of a steam turbine high-pressure valve group provided by the present invention;

[0024] Figure 5 An axonometric diagram of the use state of the lifting device for disassembly and maintenance of the steam turbine high-pressure valve group provided by the present invention;

[0025] Figure 6 for Figure 5 The left view shows the lifting device in use for disassembly and maintenance of the steam turbine high-pressure valve group.

[0026] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0027] 1. Long column; 2. Short column; 3. Crossbeam; 4. Slide rail; 5. Valve body; 6. Valve bracket; 7. Lifting hoist; 8. Valve core; 9. Connecting seat; 10. Diagonal support; 11. Upper cross bar; 12. Lower cross bar; 13. Connecting screw; 14. Hanging plate; 15. Hanging hole; 16. Hanging joint; 17. Counterweight shaft; 18. Fixed plate; 19. Counterweight block; 20. Connecting ribs. DETAILED DESCRIPTION

[0028] The principles and features of the present invention are described below in conjunction with the accompanying drawings and specific embodiments. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0029] Figure 1 and 2 As shown in the figure, the high-pressure main steam valve group of the existing steam turbine is composed of two groups of upper and lower high-pressure regulating valves and high-pressure main steam valves, and is fixed on the turbine bedplate through valve brackets. Each group of high-pressure valve groups is mainly composed of servo motors, actuators, valve covers, valve cores, valve seats and valve bodies. According to the inspection and maintenance requirements, at least a single group of high-pressure regulating valves and valve cores of high-pressure main steam valves in the upper or lower high-pressure main steam valve group need to be disassembled for inspection and maintenance.

[0030] In the description of the present invention, if terms indicating orientation such as "up", "down", "left", "right", "top", "bottom", "inside" and "outside" are used, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0031] like Figures 3 to 6As shown, the present invention provides a lifting device for disassembly and maintenance of a high-pressure valve group of a steam turbine, which includes a supporting mechanism and a lifting mechanism, wherein the supporting mechanism includes a long column 1 and a short column 2 arranged vertically, and a horizontal beam 3 and a slide rail 4 arranged horizontally, wherein the long column 1 has two and is respectively arranged on both sides in front of a valve support 6, the lower end of the long column 1 is connected to a ground anchoring portion, the upper ends of the two long columns 1 are respectively connected to the two ends of the cross beam 3, the lower end of the short column 2 is connected to the top surface of a valve body 5 or the top extension structure of the valve support 6, one end of the slide rail 4 is connected to the middle part of the cross beam 3, and the other end is connected to the upper end of the short column 2, and the lifting mechanism includes a lifting hoist 7 slidably connected to the slide rail 4, the lifting hoist 7 is connected to a valve core 8 to be disassembled through a lifting tool and a counterweight tool and keeps the valve core 8 suspended in the air and in a horizontal axial direction after leaving the valve body 5.

[0032] In other words, if Figure 3 As shown, the main structure of the support mechanism includes two long vertical columns (long columns) and shorter vertical columns (short columns) rooted on the upper valve body. The two long columns are connected at the top by a crossbeam. The short columns and crossbeam rooted on the valve body are used for the installation of the hoisting slide rail. The height design of the column is determined according to the installation height of the high-pressure main steam valve group and the inspection and maintenance operation space requirements. The length of the crossbeam is determined according to the lateral span of the valve and the reserved operation space on both sides.

[0033] In one embodiment of the present invention, the ground anchoring portion is a pre-buried anchor disposed on the ground, and the portion of the pre-buried anchor exposed from the ground is provided with a connector that cooperates with the lower end of the long column 1 for detachable connection.

[0034] It should be noted that the ground anchoring portion here should be understood in a broad sense, that is, it includes the ground in the conventional sense (usually a concrete ground) and also includes the turbine bedplate or similar supporting platform for installing turbine-related components.

[0035] In one embodiment of the present invention, the cross beam 3 is detachably connected to the long column 1 and the slide rail 4 by bolts, the slide rail 4 is detachably connected to the short column 2 by bolts, and the lower end of the short column 2 is detachably connected to the connecting seat 9 arranged at the top of the valve body 5 by bolts.

[0036] It should be noted that bolt assemblies are used to connect the long and short columns, beams, diagonal braces, slide rails and other components. The bolt assembly connection not only ensures the firmness of the connection, but also facilitates disassembly and installation. At the same time, the connection between the long and short columns and the ground also adopts a detachable anchoring structure, which can quickly separate the column from the ground when the support mechanism needs to be moved or disassembled. The design of the entire support mechanism fully considers the detachability of the structure and occupies as little installation space as possible, so as to facilitate transportation, storage and on-site disassembly and assembly.

[0037] In one embodiment of the present invention, a diagonal brace 10 is connected between the lower side of the cross beam 3 and the inner side of the long column 1 for reinforcement.

[0038] It should be noted that the diagonal brace is an auxiliary supporting structure, which is set at the connection between the beam and the column to effectively disperse the stress at the connection between the beam and the column, and is used to improve the overall stability of the supporting mechanism.

[0039] In one embodiment of the present invention, the lifting hoist 7 is an electric hoist or a hand chain hoist.

[0040] It should be noted that a manual or electric hoist is installed on the lifting rail as a lifting device, and the selection of the manual or electric hoist is determined based on the maximum total weight of the lifting components and auxiliary tools.

[0041] In one embodiment of the present invention, the long column 1, the short column 2 and the crossbeam 3 are H-shaped steels, and the slide rail 4 is an I-shaped steel.

[0042] In one embodiment of the present invention, Figure 4 As shown, the lifting tool comprises an upper cross bar 11, a lower cross bar 12 and connecting screws 13 on the left and right sides, wherein the upper end of the connecting screw 13 is connected to one side of the upper cross bar 11, and the lower end is connected to one side of the lower cross bar 12. A hanging plate 14 is fixed to the top of the upper cross bar 11, and a hanging hole 15 is provided on the hanging plate 14 for the hook of the lifting hoist 7 to be hung, and a hanging joint 16 for connecting to a counterweight tool is provided at the bottom of the lower cross bar 12.

[0043] It should be noted that the lifting tool of the above structure is in the shape of a rectangular frame as a whole, and the lifting pulling force is transmitted through the connecting screws on both sides. Its advantage is that the hollow part of the rectangular frame can effectively avoid the upper valve group, so it can effectively avoid the interference of the upper valve group on the lifting and disassembly of the valve core of the lower valve group. The upper and lower ends of the connecting screw are locked with the ends of the upper and lower cross bars by nuts, and the spacing between the upper and lower cross bars can be adjusted by the different locking positions of the above nuts. The lower end of the holding joint is U-shaped fork, and the fork mouth can be inserted into the upper end of the connecting rib plate on the upper side of the counterweight tool, and fixed by a laterally inserted pin.

[0044] In one embodiment of the present invention, Figure 5 and 6 As shown, the counterweight tool includes a counterweight shaft 17, a fixed plate 18, a counterweight block 19 and a plurality of connecting ribs 20. The counterweight shaft 17 is coaxial with the fixed plate 18 and the central axis is in the horizontal direction. One end of the counterweight shaft 17 is connected to the fixed plate 18 through a plurality of connecting ribs 20 arranged at intervals in the circumferential direction. The other end of the counterweight shaft 17 is connected to the counterweight block 19. The fixed plate 18 is used to be detachably connected to the valve core 8 to be disassembled by bolts. At least one of the connecting ribs 20 is vertically arranged and has a hanging hole at the top thereof that matches the hanging joint 16. The counterweight block 19 is cylindrical and detachably sleeved on the counterweight shaft 17.

[0045] It should be noted that the counterweight block can be set in multiple specifications to adapt to valve cores of different specifications. The counterweight block and the counterweight shaft can be detachably connected in a manner that they can be put on and moved to a suitable position and then positioned by tightening the locking bolts.

[0046] The installation and use process of the lifting device for disassembly and maintenance of the steam turbine high-pressure valve group provided by the present invention is as follows:

[0047] Before overhauling the high-pressure valve group of the steam turbine, firstly, lift two long columns to the foundation installation position, and fix the bottom of the column to the middle connecting plate (ground anchoring part) welded to the buried plate by bolts; then lift the beam to the installation position on the top of the column, accurately align the beam with the corresponding connecting parts on the top of the two columns, insert the bolt connection assembly to connect and fix; then lift the short column and install and fix it on the top of the upper valve group with bolts; lift the slide rail with a mobile lifting device (hoisting hoist) to the corresponding position, accurately align it with the connecting part between the top of the short column and the bottom of the beam, and insert the bolt assembly to connect and fix; finally, install and fix two diagonal braces between the beam and the two columns with the bolt connection assembly to disperse the stress at the connecting part and improve the overall stability of the support mechanism.

[0048] When disassembling and overhauling the upper valve group, first disassemble the servo motor, actuator, and valve cover in sequence, then use the valve-specific disassembly counterweight device (counterweight tool) in conjunction with the mobile lifting device, adjust the position of the counterweight block to keep the valve core horizontal, manually or through auxiliary tools to pull the valve core horizontally outward, and move the valve core from the inside to the outside along the slide rail, so as to effectively remove the valve core. During the separate disassembly and overhaul of the lower valve group, the servo motor of the upper valve is disassembled first to avoid the influence of its attached connecting cables and pipelines on the lower valve hoisting process. Then disassemble the servo motor, actuator, and valve cover of the lower valve in sequence, and then use a special lifting tool, combined with the valve-specific disassembly counterweight device, adjust the position of the counterweight block, so that the valve core remains horizontal during the disassembly process, and moves from the inside to the outside along the slide rail, so as to effectively remove the valve core. After the maintenance of the high-pressure valve group of the turbine is completed, the support mechanism for disassembly and overhaul should be disassembled in an orderly manner. The disassembly steps are disassembly of the diagonal brace, disassembly of the slide rail, disassembly of the short column, disassembly of the crossbeam, and disassembly of the column.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A lifting device for disassembling and repairing a high-pressure valve group of a steam turbine, characterized in that: The invention comprises a supporting mechanism and a lifting mechanism, wherein the supporting mechanism comprises a long column (1) and a short column (2) arranged vertically, and a horizontal beam (3) and a slide rail (4) arranged horizontally. The two long columns (1) are provided and are respectively arranged on both sides in front of the valve support (6). The lower end of the long column (1) is connected to the ground anchoring part, and the upper ends of the two long columns (1) are respectively connected to the two ends of the cross beam (3). The lower end of the short column (2) is connected to the top surface of the valve body (5) or the top extension structure of the valve support (6). One end of the slide rail (4) is connected to the middle part of the cross beam (3), and the other end is connected to the upper end of the short column (2). The lifting mechanism comprises a lifting hoist (7) slidably connected to the slide rail (4). The lifting hoist (7) is connected to the valve core (8) to be disassembled through a lifting tool and a counterweight tool, and keeps the valve core (8) suspended in the air and in a horizontal axial direction after leaving the valve body (5).

2. A lifting device for disassembling and repairing a steam turbine high-pressure valve group according to claim 1, characterized in that: The ground anchoring portion is a pre-buried anchor member arranged on the ground, and the part of the pre-buried anchor member exposed from the ground is provided with a connecting head which cooperates with the lower end of the long column (1) for detachable connection.

3. A lifting device for disassembling and repairing a steam turbine high-pressure valve group according to claim 1, characterized in that: The crossbeam (3) is detachably connected to the long column (1) and the slide rail (4) by bolts, the slide rail (4) is detachably connected to the short column (2) by bolts, and the lower end of the short column (2) is detachably connected to a connecting seat (9) provided at the top of the valve body (5) by bolts.

4. A lifting device for disassembling and repairing a steam turbine high-pressure valve group according to claim 1, characterized in that: A diagonal brace (10) for strengthening is also connected between the lower side of the cross beam (3) and the inner side of the long column (1).

5. A lifting device for disassembling and repairing a steam turbine high-pressure valve group according to claim 1, characterized in that: The lifting hoist (7) is an electric hoist or a hand chain hoist.

6. A lifting device for disassembling and repairing a steam turbine high-pressure valve group according to claim 1, characterized in that: The long column (1), the short column (2) and the crossbeam (3) are H-shaped steels, and the slide rail (4) is an I-shaped steel.

7. A lifting device for disassembling and repairing a steam turbine high-pressure valve group according to any one of claims 1 to 6, characterized in that: The lifting tool comprises an upper cross bar (11), a lower cross bar (12) and connecting screws (13) on left and right sides, wherein the upper end of the connecting screw (13) is connected to one side of the upper cross bar (11), and the lower end is connected to one side of the lower cross bar (12).

8. A lifting device for disassembling and repairing a steam turbine high-pressure valve group according to claim 7, characterized in that: A hanging plate (14) is fixed on the top of the upper cross bar (11), and a hanging hole (15) for hanging the hook of the lifting hoist (7) is provided on the hanging plate (14). A hanging joint (16) for connecting to a counterweight tool is provided at the bottom of the lower cross bar (12).

9. A lifting device for disassembling and repairing a steam turbine high-pressure valve group according to claim 8, characterized in that: The counterweight tool comprises a counterweight shaft (17), a fixed plate (18), a counterweight block (19) and a plurality of connecting ribs (20); the counterweight shaft (17) is coaxial with the fixed plate (18) and the central axes are both in the horizontal direction; one end of the counterweight shaft (17) is connected to the fixed plate (18) via a plurality of connecting ribs (20) arranged at circumferential intervals; the other end of the counterweight shaft (17) is connected to the counterweight block (19); the fixed plate (18) is used to be detachably connected to the valve core (8) to be disassembled via bolts; at least one of the connecting ribs (20) is vertically arranged and has a hanging hole at the top end thereof that matches the hanging joint (16).

10. A lifting device for disassembling and repairing a steam turbine high-pressure valve group according to claim 9, characterized in that: The counterweight block (19) is cylindrical and can be detachably sleeved on the counterweight shaft (17).

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