Mechanical sealing device of pipeline conveying oil pump
By setting a spring between the pressure gland and the push ring and using a static ring seal ring to block the medium contact, the problem of spring blockage in traditional spring mechanical sealing devices is solved, and the stability and reliability of mechanical seals are achieved.
Patent Information
- Application Number
- CN202422400811.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2025-08-15
- Estimated Expiration
- 2034-09-30
AI Technical Summary
In traditional spring mechanical sealing devices, springs are prone to blockage of spring gaps when they come into contact with the medium, resulting in seal failure and unable to meet the production requirements of the petrochemical pipeline industry.
Set the spring between the pressure gland and the push ring, and separate the spring from the medium through a static ring sealing ring to prevent the spring from contacting the medium, ensure that the spring is subjected to uniform force, and maintain the optimal fit state of the end surface of the moving ring.
The stability and reliability of mechanical seals are achieved, the spring blockage problem is avoided, and the long-term and effective operation of the sealing device is ensured.
Smart Images
Figure CN223227848U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of mechanical sealing devices, in particular to a mechanical sealing device for a pipeline oil pump. Background Art
[0002] Crude oil pumps and finished gasoline and diesel pumps are among the equipment most prone to seal failure in the petrochemical pipeline industry. Their operating efficiency and reliability depend largely on the structural design of the seal. When the spring in a traditional spring mechanical seal comes into contact with the medium, the medium easily clogs the spring gap, causing the spring to lose its elasticity and seal failure, which cannot meet actual production requirements. Utility Model Content
[0003] The purpose of the utility model is to provide a mechanical seal device for a pipeline oil pump, which solves the problem mentioned in the background technology that when the spring in the traditional spring mechanical seal device contacts the medium, the medium easily blocks the spring gap, causing the spring to lose its elasticity and seal failure, and the device is not resistant to high pressure and cannot meet the actual production requirements.
[0004] The utility model adopts the following technical solutions:
[0005] The utility model discloses a mechanical sealing device for a pipeline oil pump, comprising a dynamic ring seat, a dynamic ring, a static ring and a gland assembly, wherein the dynamic ring seat is sealed and fixedly connected to the dynamic ring, the dynamic ring is tightly fitted with the static ring, the gland assembly comprises a gland, and the static ring is sealed with the gland via a static ring sealing ring; a push ring and a plurality of springs are provided in the gland, the push ring is pressed against the static ring, one end of the spring is tightly in contact with the gland, and the other end of the spring is tightly in contact with the push ring.
[0006] Furthermore, the dynamic ring seat, the dynamic ring, the static ring and the gland assembly are sequentially sleeved on the shaft sleeve, the dynamic ring seat is sealed and fixedly connected to the shaft sleeve, and the static ring is rotatably connected to the shaft sleeve.
[0007] Furthermore, a sleeve sealing ring groove is provided on the inner side of the sleeve, and a sleeve sealing ring is provided in the sleeve sealing ring groove.
[0008] Furthermore, the dynamic ring and the dynamic ring seat are sealed and connected via a dynamic ring sealing ring, and the dynamic ring and the dynamic ring seat are fixedly connected and matched via pins; the dynamic ring seat and the shaft sleeve are sealed and connected via a dynamic ring seat sealing ring, and the dynamic ring seat and the shaft sleeve are fixedly connected and matched via pins.
[0009] Furthermore, the contact surface between the dynamic ring and the dynamic ring seat is enclosed to form a dynamic ring sealing ring groove, and the dynamic ring sealing ring is arranged in the dynamic ring sealing ring groove; a first limit pin hole is provided on the contact surface between the dynamic ring and the dynamic ring seat, and a corresponding second limit pin hole is provided on the dynamic ring seat, and the first limit pin hole and the second limit pin hole are fixedly connected and matched by a first pin; a dynamic ring seat sealing ring groove is provided on the contact surface between the dynamic ring seat and the shaft sleeve, and a dynamic ring seat sealing ring is provided in the dynamic ring seat sealing ring groove; a first positioning hole is provided on the side wall of the dynamic ring seat perpendicular to the center axis direction, and a corresponding second positioning hole is provided on the shaft sleeve, and the first positioning hole and the second positioning hole are fixedly connected and matched by a second pin.
[0010] Furthermore, a static ring cavity is provided in the pressure cover, and the static ring, the push ring and the spring are all provided in the static ring cavity; a static ring sealing ring groove is provided on the static ring cavity, and the static ring sealing ring is provided in the static ring sealing ring groove.
[0011] Furthermore, an annular inner protrusion is provided in the static ring cavity, and a plurality of spring holes are provided on the annular inner protrusion. The spring holes are evenly distributed in a circular ring shape. The spring is provided in the spring hole, and one end of the spring is tightly against the spring hole, and the other end of the spring is tightly against the push ring.
[0012] Furthermore, the side wall of the push ring is provided with an annular boss, and the spring is press-fitted with the annular boss.
[0013] Furthermore, a plurality of reserved holes are provided on the annular boss; a plurality of anti-rotation pin holes are provided on the annular inner protrusion, and the anti-rotation pin holes correspond to the reserved holes; an anti-rotation pin is provided in the anti-rotation pin hole, and the anti-rotation pin passes through the anti-rotation pin hole and the reserved hole to connect the push ring and the pressure cover.
[0014] Furthermore, the pressure cover is fixedly connected to the limiting plate by bolts, and a limiting groove is provided on the shaft sleeve, and the limiting groove is embedded and matched with the limiting plate.
[0015] The shaft sleeve is provided with a clamping assembly, which is tightly sleeved on the shaft sleeve and the pump shaft. The clamping assembly is located on a side of the limiting plate away from the gland.
[0016] The clamping assembly includes a clamping ring and a locking ring. The clamping ring is an open circular ring structure. The clamping ring is tightly sleeved on the shaft sleeve. The cross section of the side wall of the clamping ring is an outwardly convex isosceles trapezoidal structure. Two locking rings are provided. The locking ring is a closed circular ring structure. The cross section of the side wall of the locking ring is an inwardly concave right-angled trapezoidal structure. The two locking rings are clamped on both sides of the clamping ring, and the inner side walls of the two locking rings cooperate with the outer side walls of the clamping ring.
[0017] The two locking rings are both provided with locking threaded holes, and the locking threaded holes on the two locking rings are connected by set screws.
[0018] Compared with the prior art, the beneficial technical effects of the present invention are:
[0019] The utility model arranges the spring between the pressure cover and the push ring, and the static ring sealing ring isolates the spring from the medium. The spring cannot contact the medium and no blockage occurs, so that the dynamic ring is evenly stressed and the end faces are always installed in the best fitting state, thereby ensuring the stability of the mechanical seal working state. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The present invention will be further described below with reference to the accompanying drawings.
[0021] Figure 1 This is a schematic diagram of the structure of the mechanical seal device for the pipeline oil pump of the utility model;
[0022] Figure 2 This is a schematic structural diagram of the static ring and gland assembly in the mechanical seal device of the pipeline oil pump of the utility model;
[0023] Figure 3 This is a front view of the push ring in the mechanical seal device of the pipeline oil pump of the utility model;
[0024] Figure 4 This is a cross-sectional view of the push ring in the mechanical seal device of the pipeline oil pump of the utility model;
[0025] Figure 5 This is a schematic diagram of the gland structure in the mechanical seal device of the pipeline oil pump of the utility model;
[0026] Figure 6 This is a schematic diagram of the structure of the shaft sleeve, dynamic ring and dynamic ring seat in the mechanical seal device of the pipeline oil pump of the utility model;
[0027] Figure 7 This is a schematic diagram of the structure of the clamping assembly in the mechanical seal device of the pipeline oil pump of the utility model;
[0028] Figure 8 This is a schematic diagram of the structure of the clamping ring in the mechanical seal device of the pipeline oil pump of the utility model;
[0029] Figure 9 This is a schematic diagram of the locking ring structure in the mechanical seal device of the pipeline oil pump of the utility model;
[0030] Figure 10 This is a schematic diagram of the limit plate structure in the mechanical seal device of the pipeline oil pump of the utility model.
[0031] Explanation of reference numerals: 1. sleeve; 1-1. sleeve sealing ring; 1-2. second positioning hole; 1-3. sleeve sealing ring groove; 1-4. limiting groove; 1-5. slit; 2. gland assembly; 2-1. gland; 2-2. spring hole; 2-3. spring; 2-4. annular inner protrusion; 2-5. push ring; 2-6. anti-rotation pin hole; 2-7. anti-rotation pin; 2-8. static ring cavity; 2-9. reserved hole; 2-10. annular boss; 3. dynamic ring; 3-1. dynamic ring sealing ring; 3-2. First limit pin hole; 3-3, dynamic ring sealing ring groove; 4, static ring; 4-1, static ring sealing ring; 4-2, static ring sealing ring groove; 5, clamping assembly; 5-1, clamping ring; 5-2, locking ring; 5-3, locking threaded hole; 5-4, set screw; 6, limit plate; 7, bolt; 8, dynamic ring seat; 8-1, second limit pin hole; 8-2, dynamic ring seat sealing ring; 8-3, first positioning hole; 8-4, dynamic ring seat sealing ring groove; 8-5, first pin; 8-6, second pin. DETAILED DESCRIPTION
[0032] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.
[0033] like Figures 1 to 5 As shown, this embodiment discloses a mechanical seal device for a pipeline oil pump, comprising a dynamic ring seat 8, a dynamic ring 3, a stationary ring 4, and a gland assembly 2. The dynamic ring seat 8, the dynamic ring 3, the stationary ring 4, and the gland assembly 2 are all sleeved on the outside of a shaft sleeve 1. The dynamic ring seat 8 is sealed and fixedly connected to the shaft sleeve 1, the dynamic ring seat 8 is sealed and fixedly connected to the dynamic ring 3, the dynamic ring 3 and the stationary ring 4 are tightly fitted, and the stationary ring 4 is rotatably connected to the shaft sleeve 1. The gland assembly 2 includes a gland 2-1, and the stationary ring 4 is sealed and engaged with the gland 2-1 via a stationary ring seal 4-1.
[0034] A push ring 2-5 and several springs 2-3 are provided in the pressure cover 2-1. The push ring 2-5 presses against the static ring 4. One end of the spring 2-3 is in close contact with the pressure cover 2-1, and the other end of the spring 2-3 is in close contact with the push ring 2-5.
[0035] In this embodiment, a static ring cavity 2-8 is provided within the gland 2-1. The static ring 4, push ring 2-5, and spring 2-3 are disposed within the static ring cavity 2-8. An annular boss 2-10 is provided on the sidewall of the push ring 2-5. A static ring sealing groove 4-2 is provided within the static ring cavity 2-8. The static ring sealing ring 4-1 is disposed within the static ring sealing groove 4-2. An annular inner protrusion 2-4 is provided within the static ring cavity 2-8. A plurality of spring holes 2-2 are disposed within the annular inner protrusion 2-4. In this embodiment, there are 22 spring holes 2-2, which are evenly distributed in a circular pattern. A spring 2-3 is disposed within the spring hole 2-2. One end of the spring 2-3 abuts tightly against the spring hole 2-2, and the other end of the spring 2-3 abuts tightly against the annular boss 2-10.
[0036] like Figure 3 and Figure 4 As shown, the annular boss 2-10 is provided with a plurality of pre-set holes 2-9, and the annular inner protrusion 2-4 is provided with a plurality of anti-rotation pin holes 2-6, which correspond to the pre-set holes 2-9. In this embodiment, there are four anti-rotation pin holes 2-6 and four pre-set holes 2-9. Anti-rotation pins 2-7 are disposed within the anti-rotation pin holes 2-6. The anti-rotation pins 2-7 pass through the anti-rotation pin holes 2-6 and the pre-set holes 2-9 to connect the push ring 2-5 to the gland 2-1, allowing the push ring 2-5 to move axially of the sleeve 1 but preventing circumferential rotation.
[0037] like Figure 6 As shown, in this embodiment, a sleeve sealing ring groove 1-3 is provided on the inner side of the sleeve 1, a sleeve sealing ring 1-1 is provided in the sleeve sealing ring groove 1-3, and the sleeve 1 is sealed and connected to the rotating shaft through the sleeve sealing ring 1-1.
[0038] The dynamic ring 3 and dynamic ring seat 8 are sealed together via a dynamic ring seal 3-1, which is fixedly connected to the dynamic ring seat 8 by a pin. Specifically, the contact surfaces of the dynamic ring 3 and the dynamic ring seat 8 enclose a dynamic ring seal groove 3-3, within which the dynamic ring seal 3-1 is disposed. A first stopper pin hole 3-2 is provided on the contact surface between the dynamic ring 3 and the dynamic ring seat 8, and a corresponding second stopper pin hole 8-1 is provided on the dynamic ring seat 8. The first stopper pin hole 3-2 and the second stopper pin hole 8-1 are fixedly connected by a first pin 8-5.
[0039] The dynamic ring seat 8 is sealed to the shaft sleeve 1 via a dynamic ring seat sealing ring 8-2, which is then fixedly connected to the shaft sleeve 1 via a pin. Specifically, a dynamic ring seat sealing ring groove 8-4 is provided on the contact surface between the dynamic ring seat 8 and the shaft sleeve 1, and the dynamic ring seat sealing ring 8-2 is positioned within the dynamic ring seat sealing ring groove 8-4. A first positioning hole 8-3 is provided on the side wall of the dynamic ring seat 8, perpendicular to the central axis. A corresponding second positioning hole 1-2 is provided on the shaft sleeve 1. The first positioning hole 8-3 and the second positioning hole 1-2 are fixedly connected via a second pin 8-6.
[0040] like Figure 1 、 Figure 6 and Figure 10 As shown, the gland 2-1 is fixedly connected to the limit plate 6 by bolts 7, thereby fixing the limit plate 6 and the entire gland assembly 2 together through the bolts 7. The shaft sleeve 1 is provided with limit grooves 1-4 that cooperate with the limit plate 6. The outer edge of the limit plate 6 is embedded in the limit grooves 1-4, and the cooperation between the two prevents the shaft sleeve 1 from axial sliding.
[0041] like Figure 1 and Figures 6 to 9 As shown, in this embodiment, a clamping assembly 5 is provided on the sleeve 1, and the clamping assembly 5 is located on the side of the limit plate 6 away from the pressure cover 2-1. Specifically, the clamping assembly 5 includes a clamping ring 5-1 and a locking ring 5-2. The clamping ring 5-1 is an open circular ring structure, and the cross-section of the side wall of the clamping ring 5-1 is an outwardly convex isosceles trapezoidal structure. There are two locking rings 5-2, which are closed circular ring structures. The cross-section of the side wall of the locking ring 5-2 is an inwardly concave right-angled trapezoidal structure. The two locking rings 5-2 are clamped on both sides of the clamping ring 5-1, and the inner side walls of the two locking rings 5-2 cooperate with the outer side walls of the clamping ring 5-1. Both locking rings 5-2 are provided with locking threaded holes 5-3, and the locking threaded holes 5-3 on the two locking rings 5-2 are connected by a set screw 5-4.
[0042] In this embodiment, a plurality of slits 1-5 are provided on the side wall of the shaft sleeve 1 at a location that cooperates with the clamping assembly 5. In this embodiment, there are four slits 1-5. The clamping ring 5-1 is tightly fitted on the shaft sleeve 1.
[0043] Clamp the two locking rings 5-2 on both sides of the clamping ring 5-1, align the locking threaded holes 5-3, then put the locking ring 5-2 and the clamping ring 5-1 on the shaft sleeve 1, and finally insert the fastening screws 5-4 into the locking threaded holes 5-3 of the two locking rings 5-2 and tighten them with force. The locking ring 5-2 will squeeze the clamping ring 5-1 toward the middle. The clamping ring 5-1 itself is an open structure. Under the extrusion effect, the shaft sleeve 1 will shrink and deform at the slit 1-5 position, thereby making the shaft sleeve 1 tightly sleeved on the pump shaft. When the pump shaft rotates, it will drive the shaft sleeve 1 to rotate, achieving the effect of transmitting torque.
[0044] like Figures 1 to 10 As shown, the assembly process of the utility model is as follows:
[0045] First, place the shaft sleeve seal ring 1-1 in the groove of the shaft sleeve 1, install the dynamic ring seat seal ring 8-2 into the dynamic ring seat 8, and then fit the dynamic ring seat 8 onto the shaft sleeve 1. Install the second pin 8-6 to secure the dynamic ring seat 8 to the shaft sleeve 1. Then, fit the dynamic ring 3 onto the outer circle of the shaft sleeve 1, install the dynamic ring seal ring 3-1, and securely connect the dynamic ring 3 to the dynamic ring seat 8 using the first stop pin hole 3-2 and the second stop pin hole 8-1 via the first pin 8-5.
[0046] Install the spring 2-3 into the spring hole 2-2, and the push ring 2-5 into the static ring cavity 2-8 of the gland 2-1. Use the anti-rotation pin hole 2-6, anti-rotation pin 2-7, and the reserved hole 2-9 of the push ring 2-5 to limit the push ring 2-5 to prevent circumferential rotation. Then install the static ring seal 4-1 and the static ring 4 into the static ring cavity 2-8. The gland assembly 2 is assembled. Then, insert the gland assembly 2 into the shaft sleeve 1 so that the static ring 4 and the dynamic ring 3 fit tightly.
[0047] Install the limit plate 6 on one side of the gland assembly 2, tighten the bolts 7, and assemble the gland assembly 2 and the sleeve 1 with the help of the limit plate 6. The outer edge of the limit plate 6 fits into the limit groove 1-4 to prevent the axial sliding of the sleeve 1. Then, insert the assembled locking ring 5-2 and clamping ring 5-1 into the side of the sleeve 1 near the limit plate 6, and make the clamping ring 5-1 fit over the slit 1-5 of the sleeve 1. Install the set screws 5-4 into the locking threaded holes 5-3 of the two locking rings 5-2 and tighten them firmly. Under the squeezing action of the locking ring 5-2, the clamping ring 5-1 will shrink toward the center axis of the sleeve 1 and the pump shaft, causing the sleeve 1 to shrink and deform at the slit 1-5, thereby fastening the sleeve 1 to the pump shaft and completing the fastening function.
[0048] The spring 2-3 in the device does not contact the medium, and the spring 2-3 will not be blocked, so that the dynamic ring 3 is evenly stressed and the end face is always installed in the best fitting state, ensuring the stability of the mechanical seal working state.
[0049] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements to the technical solutions of the present invention made by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.
Claims
1. A mechanical seal device for a pipeline oil pump, comprising a dynamic ring seat (8), a dynamic ring (3), a static ring (4) and a gland assembly (2), wherein the dynamic ring seat (8) is sealed and fixedly connected to the dynamic ring (3), and the dynamic ring (3) and the static ring (4) are tightly fitted, and is characterized in that: The gland assembly (2) comprises a gland (2-1), the static ring (4) is sealed with the gland (2-1) via a static ring sealing ring (4-1); a push ring (2-5) and a plurality of springs (2-3) are provided in the gland (2-1), the push ring (2-5) is pressed against the static ring (4), one end of the spring (2-3) is in close contact with the gland (2-1), and the other end of the spring (2-3) is in close contact with the push ring (2-5).
2. The mechanical sealing device for a pipeline oil pump according to claim 1, characterized in that: The dynamic ring seat (8), the dynamic ring (3), the static ring (4) and the pressure cover assembly (2) are sequentially sleeved on the shaft sleeve (1); the dynamic ring seat (8) is sealed and fixedly connected to the shaft sleeve (1); and the static ring (4) is rotatably connected to the shaft sleeve (1).
3. The mechanical seal device for a pipeline oil pump according to claim 2, characterized in that: A shaft sleeve sealing ring groove (1-3) is provided on the inner side of the shaft sleeve (1), and a shaft sleeve sealing ring (1-1) is provided in the shaft sleeve sealing ring groove (1-3).
4. The mechanical seal device for a pipeline oil pump according to claim 2, characterized in that: The dynamic ring (3) and the dynamic ring seat (8) are sealed and connected via a dynamic ring sealing ring (3-1), and the dynamic ring (3) and the dynamic ring seat (8) are fixedly connected and matched via pins; The dynamic ring seat (8) and the shaft sleeve (1) are sealed and connected via a dynamic ring seat sealing ring (8-2), and the dynamic ring seat (8) and the shaft sleeve (1) are fixedly connected and matched via pins.
5. The mechanical sealing device for pipeline oil pump according to claim 4, characterized in that: The contact surfaces of the dynamic ring (3) and the dynamic ring seat (8) enclose a dynamic ring sealing ring groove (3-3), and the dynamic ring sealing ring (3-1) is arranged in the dynamic ring sealing ring groove (3-3); A first limiting pin hole (3-2) is provided on the contact surface between the movable ring (3) and the movable ring seat (8), and a corresponding second limiting pin hole (8-1) is provided on the movable ring seat (8); the first limiting pin hole (3-2) and the second limiting pin hole (8-1) are fixedly connected and matched by a first pin (8-5); A dynamic ring seat sealing ring groove (8-4) is provided on the contact surface between the dynamic ring seat (8) and the shaft sleeve (1), and a dynamic ring seat sealing ring (8-2) is provided in the dynamic ring seat sealing ring groove (8-4); A first positioning hole (8-3) is provided on the side wall of the dynamic ring seat (8) perpendicular to the central axis direction, and a corresponding second positioning hole (1-2) is provided on the shaft sleeve (1). The first positioning hole (8-3) and the second positioning hole (1-2) are fixedly connected and matched by a second pin (8-6).
6. The mechanical seal device for a pipeline oil pump according to claim 1, characterized in that: A static ring cavity (2-8) is provided in the gland (2-1), and the static ring (4), the push ring (2-5) and the spring (2-3) are all provided in the static ring cavity (2-8); A static ring sealing ring groove (4-2) is provided on the static ring cavity (2-8), and the static ring sealing ring (4-1) is provided in the static ring sealing ring groove (4-2).
7. The mechanical seal device for a pipeline oil pump according to claim 6, characterized in that: An annular inner protrusion (2-4) is provided in the static ring cavity (2-8), a plurality of spring holes (2-2) are provided on the annular inner protrusion (2-4), the spring holes (2-2) are evenly distributed in a circular ring shape, a spring (2-3) is provided in the spring hole (2-2), one end of the spring (2-3) is tightly against the spring hole (2-2), and the other end of the spring (2-3) is tightly against the push ring (2-5).
8. The mechanical seal device for a pipeline oil pump according to claim 7, characterized in that: The side wall of the push ring (2-5) is provided with an annular boss (2-10), and the spring (2-3) is pressed and fitted with the annular boss (2-10).
9. The mechanical seal device for a pipeline oil pump according to claim 8, characterized in that: The annular boss (2-10) is provided with a plurality of reserved holes (2-9), the annular inner protrusion (2-4) is provided with a plurality of anti-rotation pin holes (2-6), and the anti-rotation pin holes (2-6) are correspondingly matched with the reserved holes (2-9); An anti-rotation pin (2-7) is provided in the anti-rotation pin hole (2-6), and the anti-rotation pin (2-7) passes through the anti-rotation pin hole (2-6) and the reserved hole (2-9) to connect the push ring (2-5) and the pressure cover (2-1).
10. The mechanical seal device for a pipeline oil pump according to claim 2, characterized in that: The gland (2-1) is fixedly connected to the limiting plate (6) via bolts (7); A limiting groove (1-4) is provided on the shaft sleeve (1), and the limiting groove (1-4) is embedded and matched with the limiting plate (6); A clamping assembly (5) is provided on the shaft sleeve (1), the clamping assembly (5) is tightly sleeved on the shaft sleeve (1), and the clamping assembly (5) is located on a side of the limiting plate (6) away from the gland (2-1); The clamping assembly (5) comprises a clamping ring (5-1) and a locking ring (5-2), wherein the clamping ring (5-1) is an open circular ring structure, and the clamping ring (5-1) is tightly sleeved on the shaft sleeve (1), and the side wall cross section of the clamping ring (5-1) is an outwardly convex isosceles trapezoidal structure, and two locking rings (5-2) are provided, and the locking rings (5-2) are a closed circular ring structure, and the side wall cross section of the locking ring (5-2) is an inwardly concave right-angled trapezoidal structure, and the two locking rings (5-2) are clamped on both sides of the clamping ring (5-1), and the inner side walls of the two locking rings (5-2) match the outer side walls of the clamping ring (5-1); The two locking rings (5-2) are both provided with locking threaded holes (5-3), and the locking threaded holes (5-3) on the two locking rings (5-2) are connected via set screws (5-4).