A device for removing a half key of a water turbine crank arm

Abstract

This invention discloses a device for removing a split key from a turbine crank arm, relating to the field of turbine crank arm split key installation technology. The device includes a guide component; a removal assembly comprising screws and a pushing component; and an anti-deviation component. This device achieves vertical guidance through the sliding engagement of the guide component with the split key. Combined with the anti-deviation component's synchronous drive of multiple pushing nuts, it ensures that multiple screws produce completely consistent axial displacement, thereby applying a uniform, coaxial pushing force to the split key. This design fundamentally eliminates the risks of key tilting, jamming, and keyway scratches caused by unilateral force application or uneven force in traditional removal processes. It enables the safe, non-destructive, and stable removal of damaged, enlarged split keys without prior removal of the end cap, significantly improving the reliability and success rate of maintenance operations.

Description

Technical Field

[0001] This invention relates to the installation technology of the split key of a water turbine crank arm, and in particular to a device for removing the split key of a water turbine crank arm. Background Technology

[0002] In the maintenance practice of turbine guide vanes, the removal of the split key connecting the crank arm and the movable guide vane, which is damaged or deformed due to long-term operation or abnormal stress, has always been a difficult point in on-site maintenance. Traditional methods usually involve using a chisel to strike laterally and a pry bar to disassemble it. This method of applying force is concentrated and difficult to control in direction. Not only is it very easy to cause the split key to crack or plastically deform and become unusable, but the resulting impact and shearing forces are also directly transmitted to the precision keyway working surfaces of the crank arm and the movable guide vane, causing keyway scratches and deformation, which seriously affects the interference fit accuracy and operational stability of subsequent assembly.

[0003] Furthermore, when one set of semi-keys is removed, the centrifugal force generated by the gravity of the guide vane and crank arm jams the other set of semi-keys, making disassembly impossible. Conventional disassembly tools become unusable due to the loss of installation references, leading to a stalemate in maintenance work. Existing technologies generally suffer from high operational risks, a high probability of secondary damage to core components, and difficulties in implementation within the confined space of the machine pit, resulting in low efficiency. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is: to address the problem that removing a split key can easily cause scratches on the keyway, and the problem that removing a single split key can cause the other split key to become stuck.

[0005] The above-mentioned technical problems are solved by the following technical solution: The present invention proposes a device for removing the split key of a water turbine crank arm, which includes a guide member for being sleeved on the outside of the split key to be removed; Multiple sets of extraction components, each set of extraction components includes a screw threadedly connected to a threaded hole on the split key, and a pusher threadedly connected to the periphery of the screw, one axial end of the pusher abutting against the guide; One axial end of the pusher abuts against the guide member; An anti-deviation assembly is used to drive multiple pushers to rotate synchronously.

[0006] In a preferred embodiment of the turbine crank arm split key removal device of the present invention: the pushing member includes a pushing nut threadedly connected to the outside of the screw, and a gasket disposed between the guide member and the pushing nut.

[0007] In a preferred embodiment of the turbine crank arm split key removal device of the present invention: the screw passes through the hollow inner cavity of the bushing and guide from top to bottom, and finally screws into the central threaded hole of the split key and tightens it.

[0008] In a preferred embodiment of the turbine crank arm split key removal device of the present invention: the lower end face of the guide member abuts against the top end face of the split key.

[0009] In a preferred embodiment of the turbine crank arm split key removal device of the present invention: the anti-deviation component includes a connecting frame connected to the outside of the screw, multiple sets of synchronizing members rotatably connected to the end of the connecting frame, and a driving member that can simultaneously drive the synchronizing members to rotate.

[0010] In a preferred embodiment of the turbine crank arm split key removal device of the present invention, the connecting frame includes a shaft hole penetrating its center and mounting holes penetrating both sides of the shaft.

[0011] In a preferred embodiment of the turbine crank arm split key removal device of the present invention: the synchronizing element is rotatably connected to the sleeve inside the mounting hole and to the synchronizing wheel at the end of the sleeve.

[0012] In a preferred embodiment of the turbine crank arm split key removal device of the present invention: the driving component includes a driving wheel meshing with one side of the synchronous wheel; The drive wheel is rotatably connected to the shaft hole.

[0013] In a preferred embodiment of the turbine crank arm split key removal device of the present invention: pin holes are circumferentially arrayed on the side walls of both the synchronous pulley and the sleeve; The pin hole secures the timing pulley and the sleeve via a locating pin.

[0014] In a preferred embodiment of the turbine crank arm split key removal device of the present invention: the inner contour of the sleeve cooperates with the push nut; The rotation of the synchronous pulley drives the sleeve to rotate, which in turn drives the push nut to rotate.

[0015] The beneficial effects of this invention are as follows: This device achieves vertical guidance through the sliding engagement of the guide member and the split key, and combined with the anti-deviation component to synchronously drive multiple push nuts, ensures that multiple screws produce completely consistent axial displacement, thereby applying a uniform and coaxial push force to the split key. This design fundamentally eliminates the risks of key tilting, jamming, and keyway scratches caused by unilateral force application or uneven force in traditional removal processes. It enables the safe, non-destructive, and stable removal of damaged and enlarged split keys without prior removal of the end cap, significantly improving the reliability and success rate of maintenance operations. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein: Figure 1 A cross-sectional schematic diagram of the turbine crank arm split key removal device of the present invention is shown; Figure 2 A schematic diagram of the application scenario of the turbine crank arm split key removal device of the present invention is shown; Figure 3 A schematic diagram of the anti-deviation component structure of the present invention is shown; Figure 4 An exploded schematic diagram of the turbine crank arm split key removal device of the present invention is shown; Figure 5 A full cross-sectional schematic diagram of the turbine crank arm split key removal device of the present invention is shown. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0018] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0019] Reference Figures 1-2 This embodiment provides a device for removing the split key of a water turbine crank arm, including a guide 1 for being sleeved on the outside of the split key to be removed; Multiple sets of extraction components 2, each set of extraction components 2 includes a screw 21 threadedly connected to the threaded hole on the split key, and a pusher 22 threadedly connected to the periphery of the screw 21, with one axial end of the pusher 22 abutting against the guide 1; One end of the jacking member 22 abuts against the guide member 1 in the axial direction; Anti-deviation component 3 is used to drive multiple pushers 22 to rotate synchronously.

[0020] Furthermore, the pusher 22 includes a pusher nut 221 threaded to the outside of the screw 21, and a washer 222 disposed between the guide 1 and the pusher nut 221.

[0021] Furthermore, the screw 21 passes through the hollow inner cavity of the bushing 222 and the guide 1 from top to bottom, and finally screws into the central threaded hole of the split key and tightens it.

[0022] Furthermore, the lower end face of guide 1 abuts against the top end face of the split key.

[0023] In this embodiment, the device is used to remove the split key 43, which is stuck between the crank arm 41 and the movable guide vane 42 due to damage and expansion in the water guide mechanism of a water turbine. The guide member 1 is a hollow cylinder with an opening at its lower end for fitting over the split key 43 to be removed. The inner diameter of the guide member 1 is slightly larger than the outer diameter of the unexpanded portion of the split key 43, forming a sliding fit to provide vertical guidance for the ejection movement of the split key 43 and prevent it from tilting and jamming.

[0024] Two sets of extraction components 2 are arranged symmetrically. Each set of extraction components 2 includes a high-strength screw 21 and a pusher 22. The thread specification of the screw 21 matches the standard threaded hole machined at the axial center position of the split key 43. The pusher 22 includes a pusher nut 221 that is threadedly engaged with the screw 21, and an annular washer 222 that is sleeved on the screw 21 and positioned between the upper end face of the guide 1 and the pusher nut 221. The washer 222 is used to increase the bearing area and evenly transmit the concentrated force applied by the pusher nut 221 to the end face of the guide 1.

[0025] During assembly, the screw 21 passes through the hollow inner cavity of the bushing 222 and the guide 1 from top to bottom, and finally screws into the central threaded hole corresponding to the split key 43 and pre-tightens. The lower end face of the guide 1 presses against the top force-bearing surface of the split key 43.

[0026] The anti-deviation component 3 ensures that the multiple jacking components 22 can achieve synchronized rotational movement. It can be achieved using various mechanical synchronization principles according to different site conditions and operational requirements.

[0027] As a preferred embodiment, the anti-deviation assembly 3 may include a linkage frame rigidly connected to all the jacking members 22. By manually or electrically driving the linkage frame to rotate, all the jacking members 22 can be directly driven to rotate at the same angular velocity and direction. The anti-deviation assembly 3 may also employ a gear transmission system, in which a driving gear simultaneously meshes with multiple driven gears that are coaxially fixed to the jacking members 22 to achieve synchronous drive.

[0028] In practical operation, the device is first assembled and positioned. The lower opening of the guide 1 is vertically fitted onto the outside of the split key 43 to be removed. Then, each screw 21 is passed through the corresponding washer 222 and the inner cavity of the guide 1 in sequence, and screwed into the pre-made threaded hole on the split key 43 until the head of the screw 21 makes slight contact with the bottom of the threaded hole of the split key 43 or reaches the preset pre-tightening torque. At this time, the lower end face of the guide 1 is firmly abutting against the top surface of the split key 43.

[0029] During removal, operate the push nut 221 to drive it to rotate. Because the push nut 221 is axially constrained by the bushing 222 and the guide 1, its rotational motion is converted into a linear displacement of the screw 21 along its axis via the threaded joint, typically resulting in an upward pull. Under this uniform pushing force, the split key 43 overcomes the jamming friction between itself and the crank arm and the keyway of the movable guide vane. Guided precisely by the inner hole of the guide 1, it is vertically and smoothly ejected as a whole, effectively preventing key tilting, jamming, or scratches on the keyway sidewalls caused by unilateral force application.

[0030] Reference Figures 3-5 As an optional embodiment, in one embodiment provided by the present invention, the anti-deviation component 3 also includes a connecting frame 31 connected to the outside of the screw 21, multiple sets of synchronizing members 32 rotatably connected to the end of the connecting frame 31, and a driving member 33 that can simultaneously drive the synchronizing members 32 to rotate.

[0031] Furthermore, the connecting bracket 31 includes a shaft hole 311 passing through its center and mounting holes 312 passing through both sides of the shaft.

[0032] Furthermore, the synchronizing element 32 is rotatably connected to the sleeve 321 inside the mounting hole 312 and to the synchronizing wheel 322 rotatably connected to the end of the sleeve 321.

[0033] Furthermore, the drive component 33 includes a drive wheel 331 that meshes with one side of the synchronous pulley 322; The drive wheel 331 is rotatably connected to the shaft hole 311.

[0034] Furthermore, pin holes 41 are circumferentially arranged on the side walls of both the synchronous pulley 322 and the sleeve 321; The pin hole 41 fixes the synchronous pulley 322 and the sleeve 321 through the positioning pin 42.

[0035] Furthermore, the inner contour of the sleeve 321 mates with the push nut 221; The rotation of the synchronous pulley 322 drives the sleeve 321 to rotate, which in turn drives the push nut 221 to rotate.

[0036] In this embodiment, the connecting frame 31 serves as a rigid support and transmission platform, and has an overall frame structure. A shaft hole 311 is machined in its center for mounting the drive shaft. On both sides of the shaft hole 311, mounting holes 312 are symmetrically machined, and the number of mounting holes 312 corresponds to the number of components 2 that can be removed. This example uses two sets.

[0037] Each synchronizing element 32 consists of a sleeve 321 and a synchronizing pulley 322. The sleeve 321 is a stepped shaft-shaped part. One end of it has a non-circular inner contour machined on its inner side for fitting with the push nut 221. The other end is a cylindrical journal, which passes through the mounting hole 312 on the connecting bracket 31 and is rotatably supported by a bearing. The end of the journal is used to connect with the synchronizing pulley 322.

[0038] Synchronizing pulley 322 is typically designed as a spur gear, which is key to achieving synchronous motion. A circular slot is provided in the center of the synchronous pulley 322, which forms a clearance fit or transition fit with the cylindrical journal at the connecting end of the sleeve 321, allowing the two to be positioned radially but to rotate temporarily relative to each other in the circumferential direction.

[0039] Multiple pin holes 41 are machined evenly in a circumferential array on the end face of the sleeve 321 and the opposite end face of the synchronous pulley 322. During assembly, the two are not pre-rigidly fixed. Instead, the push nut 221 is first fitted onto the inner hole of the sleeve 321. At this point, the sleeve 321 can be freely rotated to find the optimal engagement angle, completely unrestricted by the position of the synchronous pulley 322. After all sleeves 321 are engaged with their respective push nuts 221, each synchronous pulley 322 is rotated one by one until its pin hole 41 aligns with the pin hole 41 on the corresponding end face of the sleeve 321. Finally, the locating pin 42 is inserted to achieve final circumferential fixing.

[0040] If the sleeve and the timing pulley 322 are rigidly fixed before assembly, when fitting the sleeve's internal hexagonal hole onto the external hexagonal hole of the push nut 221, the hexagonal orientation of both must be perfectly aligned; otherwise, they cannot be fitted. Since both sets of timing pulleys 322 mesh simultaneously on both sides of the drive wheel 331, when one set of push nuts 221 rotates the timing pulley 322, the other set of timing pulleys 322 will inevitably rotate, resulting in a very low probability of proper fitting. This design allows the sleeve 321 and timing pulley 322 to rotate relative to each other in their initial state. During assembly, the worker can first freely rotate the sleeve 321, easily aligning its internal hexagonal hole with the external hexagonal hole of the push nut 21 and fitting it, completely unaffected by the timing pulley angle. After fitting, the timing pulley 322 is rotated until its pin hole 41 aligns with the pin hole 41 on the sleeve 321, and the locating pin is inserted to complete the final fixation. This greatly reduces the assembly difficulty and the precision requirements for operation. This ensures that both sets of extraction components can be extracted simultaneously, avoiding the possibility of compression and inability to extract components due to asynchronous extraction. Preferably, the drive wheel 331 of the drive member 33 is also a spur gear, which is mounted in the shaft hole 311 of the connecting bracket 31 via a drive shaft and bearings. The number of teeth of the drive wheel 331 is the same as the number of teeth of the two synchronous pulleys 322, and it meshes with the two synchronous pulleys 322 simultaneously, forming a simple fixed-axis gear train.

[0041] Preferably, a manual crank, a wrench head, or a coupling connected to a power source can be connected to the drive shaft of the drive wheel 331.

[0042] When it is necessary to synchronously eject the split key 43, the operator rotates the drive wheel 331. The rotation of the drive wheel 331 is transmitted to the two synchronizing pulleys 322 at the same speed through gear meshing. Since the two synchronizing pulleys 322 are synchronized and meshed with the drive wheel 331, they will rotate with exactly the same angular velocity and direction.

[0043] The rotation of the synchronizing pulley 322 drives the sleeve 321 to rotate synchronously via the locating pin 42. The internal hexagonal hole of the sleeve 321 then drives the jacking nut 221 that it mates with to rotate. Since the two jacking nuts 221 are driven synchronously and at the same speed, according to the motion principle of the threaded pair, the two screws 21 will generate completely consistent axial displacement speed and displacement, thereby applying a uniform and unbiased jacking force to the split key 43.

[0044] In summary, this device achieves vertical guidance through the sliding engagement of the guide component and the split key. Combined with the anti-deviation assembly, it synchronously drives multiple jacking nuts, ensuring that multiple screws produce completely consistent axial displacement, thereby applying a uniform and coaxial jacking force to the split key. This design fundamentally eliminates the risks of key tilting, jamming, and keyway scratches caused by unilateral force application or uneven force in traditional removal processes. It enables the safe, non-destructive, and stable removal of damaged and enlarged split keys without prior removal of the end cap, significantly improving the reliability and success rate of maintenance operations.

[0045] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A device for removing the split key of a water turbine crank arm, characterized in that: include, Guide (1) is used to be fitted onto the outside of the split key to be removed; Multiple sets of extraction components (2), each set of extraction components (2) includes a screw (21) threadedly connected to a threaded hole on the split key, and a pusher (22) threadedly connected to the periphery of the screw (21), one axial end of the pusher (22) abutting against the guide (1). One end of the pusher (22) abuts against the guide (1) in the axial direction. Anti-deviation component (3) is used to drive multiple pushers (22) to rotate synchronously.

2. The turbine crank arm split-key removal device according to claim 1, characterized in that: The pusher (22) includes a pusher nut (221) threaded to the outside of the screw (21) and a gasket (222) disposed between the guide (1) and the pusher nut (221).

3. The turbine crank arm split-key removal device according to claim 2, characterized in that: The screw (21) passes through the hollow inner cavity of the bushing (222) and the guide (1) from top to bottom, and finally screws into the central threaded hole of the split key and tightens it.

4. The turbine crank arm split-key removal device according to claim 3, characterized in that: The lower end face of the guide (1) abuts against the top end face of the split key.

5. The turbine crank arm split-key removal device according to any one of claims 1 to 4, characterized in that: The anti-deviation assembly (3) includes a connecting frame (31) connected to the outside of the screw (21), multiple sets of synchronizing elements (32) rotatably connected to the end of the connecting frame (31), and a driving element (33) that can simultaneously drive the synchronizing elements (32) to rotate.

6. The turbine crank arm split-key removal device according to claim 5, characterized in that: The connecting frame (31) includes a shaft hole (311) passing through its center and mounting holes (312) passing through both sides of the shaft.

7. The turbine crank arm split-key removal device according to claim 6, characterized in that: The synchronizing element (32) is rotatably connected to the sleeve (321) inside the mounting hole (312) and to the synchronizing wheel (322) at the end of the sleeve (321).

8. The turbine crank arm split-key removal device according to claim 7, characterized in that: The drive component (33) includes a drive wheel (331) meshing with one side of the synchronous pulley (322). The drive wheel (331) is rotatably connected to the shaft hole (311).

9. The turbine crank arm split-key removal device according to claim 8, characterized in that: Both the synchronous pulley (322) and the sleeve (321) have pin holes (41) arranged in a circumferential array on their side walls. The pin hole (41) fixes the synchronous pulley (322) and the sleeve (321) by the positioning pin (42).

10. The turbine crank arm split-key removal device according to claim 9, characterized in that: The inner contour of the sleeve (321) mates with the push nut (221); The rotation of the synchronous wheel (322) drives the sleeve (321) to rotate, which in turn drives the push nut (221) to rotate.

Images