CN210799348U - Split type rubber-lined double-screw pump - Google Patents

Abstract

A split rubber-lined double-screw pump belongs to the technical field of double-screw pump equipment; its structure includes initiative screw rod, driven screw rod, shell, synchro gear structure and drive arrangement, and this shell includes front end casing, bush and rear end casing, and the both ends of bush are respectively for can dismantling the front end link of being connected and can dismantle the rear end link of being connected with the rear end casing with the front end casing, and the tip of initiative transmission shaft and driven transmission shaft wears to establish with the tip of keeping away from the bush of front end casing and rear end casing respectively through the machine seal subassembly and is connected. The double-screw pump is of a combined split structure, independent maintenance and replacement of structural components are facilitated, cost investment is reduced, the processing, coating and repairing processes of the inner surface of the double-screw pump are easily achieved, and the improvement and improvement of structural performance can be further achieved. Meanwhile, the split structure arrangement improves the installation operation diversity and application flexibility of the structure, and the application range is expanded.

Description

Split type rubber-lined double-screw pump

Technical Field

The utility model belongs to the technical field of two screw pump equipment, specifically relate to a split type lining is glued two screw pump.

Background

The double-screw pump is characterized in that a pair of left and right screws with different rotation directions are matched with the inner wall of a sealing bush, a sealing cavity is gradually established in the rotation process of the screws, and the sealing cavity is continuously pushed to a discharge end along the axial direction from a suction end of the pump along with the rotation of the screws, so that the transmission operation is realized, namely the screw pump conveys liquid or pressurizes the liquid by means of the volume change and movement of an engagement space formed by a pump body and the screws. When the volume of the screw meshing space at one end of the suction cavity is gradually increased and the pressure is reduced, the liquid enters the volume of the meshing space under the action of the pressure difference. When the volume is maximized to form a sealed chamber, the liquid is continuously moved axially in the sealed chamber until it is discharged to one end of the chamber, at which time the volume of the screw engagement space at the one end of the chamber is gradually reduced, and the liquid is discharged. The screw pump has the advantages of stable medium conveying, low turbulence of the pushed medium, weak pressure pulsation, small mechanical vibration, low noise and the like. However, the screw pump has a complicated internal structure and a small internal screw meshing space, and is not suitable for conveying media containing solid impurities inside, so that on one hand, the screw pump is easy to cause abrasion of a conveying structure and reduce the conveying effect of subsequent media, and on the other hand, relatively small channel space is easy to block, so that clamping stagnation in the conveying operation process of the screw pump is caused, and the driving structure is damaged. In addition, the pump body formula structure as an organic whole of twin-screw pump is difficult for carrying out inner structure and anticorrosive material's combination operation, has reduced the maneuverability of structural performance, and consequently corrosion resisting capacity is relatively poor. In order to ensure the service life and the structural stability of the structure, the requirement on a transmission medium is high, so that the device is difficult to be applied to the conveying of untreated chemical products, and the application range of the device is limited. In addition, the integral type structure setting of this pump body has not only restricted pump body application, has also improved the cost of maintenance of device simultaneously, has reduced the flexibility and has used.

Disclosure of Invention

The utility model discloses solve the technical problem that above-mentioned prior art exists, provide a split type lining is glued double screw pump.

The above technical problem of the present invention can be solved by the following technical solutions: the utility model provides a split type lining is glued double screw pump, includes initiative screw rod, driven screw rod, shell, synchronous gear structure and drive arrangement, initiative screw rod and driven screw rod are installed in the shell, the initiative screw rod includes initiative thread drive portion and initiative transmission shaft, driven screw rod includes driven thread drive portion and driven transmission shaft, initiative transmission shaft passes through synchronous gear structure with driven transmission shaft and realizes gear synchronous transmission, initiative transmission shaft links to each other with drive arrangement's drive shaft, it holds the chamber and is provided with water inlet and delivery port to form the screw rod in the shell, the shell includes front end casing, bush and rear end casing, the bush includes front end link and rear end link, sealing connection can be dismantled with the front end casing to the front end link, sealing connection can be dismantled with the one end of rear end casing to the rear end link, the screw rod holds the chamber by front end casing, The bush and the rear end shell body are formed in an enclosing mode, the driving thread transmission portion and the driven thread transmission portion are arranged in the bush in a sleeved mode, and the end portions of the driving transmission shaft and the driven transmission shaft are connected with the end portions, far away from the bush, of the front end shell body and the rear end shell body in a penetrating mode through the mechanical seal assembly.

The shell of the double-screw pump is detachably connected with the rear end shell through the front end shell, the lining and the rear end shell to form a screw accommodating cavity, and the driving screw and the driven screw are mounted inside the shell. The driving thread transmission part and the driven thread transmission part are sleeved with the bushings, and the driving transmission shaft and the driven rotating shaft are respectively fixedly and hermetically connected with the end parts of the front end shell and the rear end shell by utilizing the mechanical seal assembly. The device is a combined split structure, the front end shell, the lining and the rear end shell are independent individuals and then are connected through the connecting piece to form a working shell, independent operation of each structure is facilitated, meanwhile, the split structure is easy to realize the reprocessing process of the inner surface, the operation flexibility of the structure is improved, and the application range of the device is further expanded.

Preferably, the front end connecting end is provided with an inner sleeve and is sleeved with the front end of the front end shell, the rear end connecting end comprises an inner sleeve and is sleeved with the rear end of the rear end shell, a middle communicating section is arranged between the front end sleeve and the rear end sleeve, and the front end shell, the lining and the rear end shell are connected through flanges.

Preferably, the synchronizing gear structure comprises a synchronizing gear box body and two meshed synchronizing gears, the synchronizing gear structure is coaxially arranged at one end of the shell, the synchronizing gear box body is detachably connected with the shell, and the synchronizing gears are respectively sleeved on a driving transmission shaft and a driven transmission shaft which extend out of the shell.

Preferably, still include reduction gear box, the drive shaft passes through reduction gear box and links to each other with drive arrangement's drive shaft, reduction gear box includes reduction gear box, drive gear and driving gear, the drive gear cover is established and is connected in the drive shaft, the driving gear cover is established and is connected in drive shaft, drive gear and driving gear meshing connection, the external diameter of driving gear is greater than drive gear's external diameter.

As preferred, shell, synchromesh gear structure, reduction gear box and drive arrangement connect gradually the setting, the reduction gear box passes through the coupling body and realizes being connected with the synchromesh gear box, another tip of shell has connected gradually pump end cover plate and pump cover, driving transmission shaft and driven transmission shaft wear to establish respectively through the bearing and connect in the pump end cover, the pump cover is provided with the transmission shaft that is used for placing driving transmission shaft and driven transmission shaft's tip towards pump end cover plate and holds the chamber, pump cover, pump end cover plate, shell, synchromesh gear box, coupling body and reduction gear box set up for coaxial coupling, pump end cover plate, shell, synchromesh gear box, coupling body and reduction gear box loop through flange structure and realize connecting.

Preferably, both ends of the synchronous gear box are provided with flange structures, and the flange structures of the shell, the synchronous gear box body, the pump end cover plate and the reduction gear box body are arranged in the same specification structure.

Preferably, inner surfaces of the screw receiving chamber, the water inlet and the water outlet are coated with a corrosion-resistant material.

Preferably, the inner surfaces of the bushings facing the driving threaded transmission part and the driven threaded transmission part are provided with bushing lining glue layers.

Preferably, the driving screw and the driven screw comprise metal brackets and rubber layers uniformly wrapped on the metal brackets.

Preferably, the metal bracket and the rubber layer are molded by a casting process, and the rubber layer is subjected to desulfurization treatment in the casting operation process.

The utility model discloses beneficial effect who has:

1. the shell adopts a split structure design, so that the operability in the shell and the connection diversity structure arrangement of the shell are improved, the application flexibility of the device is improved, the independent replacement and treatment operation of shell structure parts are facilitated, and the cost input of the device is reduced;

2. the bushing is connected with the sleeving flange at the end part of the front end shell and the end part of the rear end shell respectively, so that the connection stability of the device is improved, the integration of the structure and the compact connection of the structure of the device are easy to realize, and the reasonable application of the internal space of the device is ensured;

3. the device is arranged in a modular structure, and is provided with a synchronous gearbox body, so that the installation and maintenance of the device and the subsequent accessory replacement operation are facilitated;

4. the flange structures of the same type of the shell, the synchronous gearbox, the pump end cover plate and the reduction gear box body in the device are arranged, so that the flexibility of the connecting structure of the device is improved, the subsequent maintenance and replacement operation of the structure of the device are easy to realize, and the application range of the device is expanded;

5. the coating operation of the corrosion-resistant material improves the corrosion-resistant effect of the shell, enlarges the application range of the device and prolongs the practical life of the shell;

6. due to the arrangement of the lining glue layer of the lining, the smoothness of the inner surfaces of the lining facing the driving screw and the driven screw is improved, the reduction of the friction force between the screw and the inner wall of the shell is realized, and the service lives of the driving screw and the driven screw are prolonged;

7. the screw structure is realized in a mode that the metal framework is coated with rubber, so that the structural strength of the outer surface of the screw structure is reduced through the deformation characteristic of a rubber material, the conveying efficiency of solid particles is improved, the conveying passing rate is ensured, and the application range of the device is expanded;

8. in addition, the rubber layer and the metal framework are molded through a pouring process, the matching of the rubber layer can be matched according to the practical application environment, the structural adaptability is improved, and the structural practicability is guaranteed.

Drawings

Fig. 1 is a schematic structural view of the present invention;

FIG. 2 is an enlarged view of the area A in FIG. 1;

FIG. 3 is an enlarged view of the area B in FIG. 1;

FIG. 4 is an enlarged view of region C of FIG. 1;

fig. 5 is a schematic view of an external structure of the present invention;

fig. 6 is a schematic view of a partial cross-sectional structure of the present invention;

in the figure: 1. an end cap; 11. a drive shaft receiving cavity; 12. a positioning member; 13. a retainer ring; 2. a pump end cover plate; 21. a bearing; 3. a front end housing; 31. a water inlet; 32. a machine seal assembly; 4. a bushing; 41. the front end is sleeved with an end; 42. the rear end is sleeved with an end; 43. an intermediate communication section; 44. lining glue lining layer; 5. a rear end housing; 51. a water outlet; 52. an adjustment ring; 6. a driving screw transmission part; 61. a drive transmission shaft; 7. a driven screw transmission part; 71. a driven transmission shaft; 8. a synchronous gearbox housing; 81. a synchronizing gear; 82. a gearbox end cover; 9. a reduction gear housing; 91. a driving gear; 92. a drive gear; 93. a distance ring; 94. a drive shaft; 95. a coupling body.

Detailed Description

The technical solution of the present invention is further specifically described below by way of examples and with reference to the accompanying drawings.

Example (b): a split rubber-lined double-screw pump is shown in figures 1-6 and comprises an end cover 1, a pump end cover plate 2, a shell, a synchronous gear structure, a reduction gear box and a driving device. Only the driving shaft 94 of the driving device is drawn in the figure, and those skilled in the art can select the driving motor as the driving device in this embodiment according to the actual application environment. The enclosure forms the screw rod in this shell and holds the chamber to be provided with water inlet and delivery port and hold the transmission intercommunication effect that chamber and external environment were held in order to realize the screw rod. As shown in fig. 1, the housing is composed of a front end housing 3, a liner 4, and a rear end housing 5 detachably and sealingly connected in this order. At this time, the driving screw and the driven screw are sleeved in the shell, the driving transmission shaft 61 and the driven transmission shaft 71 close to the front end shell 3 penetrate through the outward end part of the front end shell 3 through the mechanical seal assembly 32, the sealing quality of the joint is ensured by the application of the mechanical seal assembly 32, and the leakage of a transmission medium from the joint is prevented. The other end surface of the front end shell 3 is sequentially connected with a pump cover end plate 2 and an end cover 1. The end of the pump cover end plate 2 and the front end housing 3 are connected by flanges, and are provided with bearings 21 corresponding to the driving transmission shaft 61 and the driven transmission shaft 51. The ends of the driving transmission shaft 61 and the driven transmission shaft 71 extending out of the front end housing 3 are inserted through the pump cover end plate 2 through the corresponding bearings 21. As shown in fig. 2, the end of the driven transmission shaft 71 extending out of the bearing 21 is sequentially sleeved with the connecting retaining ring 13 and the positioning member 12, so as to achieve the positioning effect of the shaft end and ensure the relative position of the driven transmission shaft 71 and the bearing 21. Similarly, the end of the driving transmission shaft 61 performs the connecting operation of the retainer ring 13 and the positioning member 12 as described above. To avoid that the ends of the driving transmission shaft 61 and the driven transmission shaft 71 are exposed to the external environment, the end cap 1 is provided with a corresponding transmission shaft receiving cavity 11 towards the pump end cover plate 2. When the end cover 1 is connected to the pump end cover plate 2, the end of the driving transmission shaft 61 and the end of the driven transmission shaft 71 are located in the transmission accommodating cavity 11, so that the influence of the external environment on the internal structure is avoided, and the stability of the structure is ensured. The structure of the transmission shaft accommodating cavity 11 can be an integral cavity for placing the end parts of the driving transmission shaft 61 and the driven transmission shaft 71, and can also be a separate split arrangement of two cavities as shown in fig. 1.

One end of the front end housing 3 is hermetically connected with the driving transmission shaft 61 and the driven transmission shaft 71, and is connected with the pump end cover plate 2 and the end cover 1. The other end of the front end housing 3 performs a coupling operation of the front end coupling end of the bush 4. The other end of the bush 4 is a rear end connection end for connecting with the rear end housing 5, respectively. In order to improve the stability of the connection structure, the front end connection end is provided with a front end sleeving end 41 sleeved on the front end shell 3, the rear end connection end is provided with a rear end sleeving end 42 sleeved on the rear end shell 5, and a middle communication section 43 is arranged between the front end sleeving end 41 and the rear end sleeving end 42. The front housing 3, the bushing 4 and the rear housing 5 are flange-connected as shown in fig. 1, and the flange structures at the two ends of the bushing 4 are respectively disposed at the connection positions of the front sheathing end 41, the rear sheathing end 42 and the intermediate connection section 43. In the connection process, the front end sleeve-setting end 41 of the bushing 4 is sleeved on the end portion of the front end housing 3 and continuously moves towards the front end housing 3 until the two flange structures contact each other, the bushing 4 and the front end housing 3 stop moving under the blocking effect of the flange structures, and then the connection and fixation of the flange structures are realized through bolts, so that the sealing connection operation process of the bushing 4 and the front end housing 3 is completed. The rear end of the other end is sleeved with the end 42, which is sleeved with one end of the rear end shell 5 and is continuously moved to the flange structure to contact, and then the bolt sequentially penetrates through the connecting through holes of the flange structure to fix the nut, so that the connecting process of the rear end connecting end of the lining 4 and the rear end shell 5 is realized. To this end, the shell is connected and is accomplished, and front end housing 3, bush 4 and rear end housing 5 surround and form the screw rod and hold the chamber, initiative thread transmission portion 6 and driven thread transmission portion 7 are towards the internal surface of bush 4, and the other end of sealing connection in rear end housing 5 is worn to establish through mechanical component 32 by the initiative transmission shaft 61 and the driven transmission shaft 71 of opposite side, this connected mode with above-mentioned front end housing 3 and initiative transmission shaft 61, driven transmission shaft 71's connected mode, thereby realize the leakproofness guarantee of tip. In addition, as shown in fig. 3, an adjusting ring 52, i.e., an oil seal sleeve corresponding to the mechanical seal assembly, is sleeved on a driving transmission shaft 61 passing through the mechanical seal assembly 32. Similarly, the driven transmission shaft 71 also performs the sleeving connection of the adjusting ring 52, and the driving transmission shaft 61 and the driven transmission shaft 71 located at the front end housing 3 also perform the sleeving connection of the adjusting ring 52, that is, the adjusting ring 52 is located between the mechanical seal assembly of the front end housing 3 and the bearing 21 of the pump end cover plate 2. To ensure the transmission efficiency, as shown in fig. 6, the inner surfaces of the bushings 4 facing the driving screw thread transmission part 6 and the driven screw thread transmission part 7 are provided with bushing lining layers 44, thereby improving the smoothness of the inner surfaces of the bushings 4, reducing the relative friction force during the transmission, and thus improving the transmission efficiency. The water inlet 31 and the water outlet 51 of the shell are respectively arranged on the front end shell 3 and the rear end shell 5, and the orientation of the water inlet 31 and the orientation of the water outlet 51 can be adjusted in the connection process according to the actual application condition.

The other end of the rear housing 5, which is connected as described above, is flange-connected to the synchronizing gear housing 8 of the synchronizing gear structure, i.e., the opposite ends of the two structures are each provided with a flange structure, and the two flange structures are connected by bolts when they are in contact with each other. As shown in fig. 3, a driving transmission shaft 61 passing through the rear housing 5 and fitted with an adjusting ring 52 passes through the end cover of the synchronizing gear housing 8, and is connected and positioned by a coaxially disposed bearing 21. At this time, the driving/driven shaft 61 and the driven transmission shaft 71 entering the synchronizing gear housing 8 are respectively connected to each other by the two synchronizing gears 81, and the synchronizing gears 81 are two identical gears in a meshing transmission state. To ensure structural stability, the end of the driven transmission shaft 71 to which the synchronizing gear 81 is connected should be subjected to a positioning operation. The corresponding driving transmission shaft 61 extends into the reduction gear box 9 and is sleeved and connected with the driving gear 91 inside the reduction gear box, and at the moment, the end part of the driving transmission shaft 61 can be positioned, so that the stability of the relative position of the connecting structure is ensured. The reduction gearbox is connected to the timing gear arrangement by means of a coupling body 95. The coupling body 95 may be flanged with the synchronizing gearbox housing 8 at one end and with the reduction gearbox housing 9 at the other end, as shown in fig. 5. And the coupling body 95 connects and positionally defines the drive transmission shaft 61, which is threaded through, by means of the bearing 21. At this time, the end of the driving rotation shaft 61 passing through the bearing 21 is fitted with the distance ring 93, and then the driving gear 91 is fitted and connected to the driving transmission shaft 61. The driving gear 91 is engaged with the driving gear 92 sleeved on the driving shaft 94, and the outer diameter of the driving gear 91 is larger than that of the driving gear 92, so that the stable operation of the speed reduction is ensured.

The end cover 1, the pump end cover plate 2, the housing, the synchronous gear box body 8, the coupling body 95 and the reduction gear box body 9 are coaxially connected. And the pump end cover plate 2, the front end shell 3, the bush 4, the rear end shell 5, the synchronous gear box body 8, the connecting body 95 and the reduction gear box body 9 are connected sequentially through the flange structure, and the flange structures can be arranged in the same specification structure for improving the universality of structural connection. The device can carry out the flexibility combination setting of structure according to actual conditions in the application, has improved device application scope. Meanwhile, the split type shell structure can be used for conveniently coating the corrosion-resistant material on the inner surface. According to the application, the staff can select anticorrosive materials such as plastics, rubber, pottery and the like and carry out the surface coating operation of screw rod holding chamber, water inlet 31 and delivery port 51, and then improved the anticorrosive effect on transmission surface, enlarged the application scope of device. In addition, the screw structure in the double-screw pump consists of a metal bracket and a rubber layer. Firstly, the metal support is produced according to the screw structure, so that the working strength of the screw structure is ensured. Then the rubber material is uniformly wrapped on the metal bracket through a pouring process to form a rubber layer. And desulfurization treatment is carried out in the casting process so as to improve the performance of the rubber layer. In the production process, the working personnel can allocate the rubber materials according to application requirements, so that the structural adaptability is improved, and the structural practicability is ensured. And the rubber layer has certain deformation characteristics, so that the structural strength of the outer surface of the screw structure can be reduced in the transmission process, the transmission surface of the screw structure is deformed under the action of solid impact to realize the stress change of the channel, the channel is enlarged, the transmission efficiency of the device to solid particles is improved, and the transmission passing rate is ensured. In addition, the arrangement of the rubber layer also improves the structural wear resistance, and the service life of the structure is ensured when the application range of the device is enlarged.

Finally, it should be noted that the above embodiments are merely representative examples of the present invention. Obviously, the present invention is not limited to the above-described embodiments, and many modifications are possible. Any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should be considered as belonging to the protection scope of the present invention.

Claims (10)

1. The utility model provides a split type lining is glued double screw pump, includes initiative screw rod, driven screw rod, shell, synchronous gear structure and drive arrangement, initiative screw rod and driven screw rod are installed in the shell, the initiative screw rod includes initiative thread transmission portion (6) and initiative transmission shaft (61), driven screw rod includes driven thread transmission portion (7) and driven transmission shaft (71), gear synchronous transmission is realized through synchronous gear structure in initiative transmission shaft (61) and driven transmission shaft (71), initiative transmission shaft (61) link to each other with drive arrangement's drive shaft (94), it holds the chamber and is provided with water inlet (31) and delivery port (51) to form the screw rod in the shell, its characterized in that, the shell includes front end casing (3), bush (4) and rear end casing (5), bush (4) include front end link and rear end link, sealing connection can be dismantled with front end casing (3) to the front end link, sealing connection can be dismantled with the one end of rear end casing (5) to the rear end link, the screw rod holds the chamber and is surrounded by front end casing (3), bush (4) and rear end casing (5) and forms, the bush (4) is located to initiative screw thread transmission portion (6) and driven screw thread transmission portion (7) cover, the tip of initiative transmission shaft (61) and driven transmission shaft (71) is worn to establish with the tip that front end casing (3) and rear end casing (5) kept away from bush (4) respectively and is connected through machine seal subassembly (32).

2. The split rubber-lined double-screw pump according to claim 1, wherein the front end connecting end is provided with a front end sleeving end (41) sleeved in the front end housing (3), the rear end connecting end comprises a rear end sleeving end (42) sleeved in the rear end housing (5), an intermediate communicating section (43) is arranged between the front end sleeving end (41) and the rear end sleeving end (42), and the front end housing (3), the lining (4) and the rear end housing (5) are in flange connection.

3. The split rubber-lined double-screw pump according to claim 1, wherein the synchronizing gear structure comprises a synchronizing gear box body (8) and two meshed synchronizing gears (81), the synchronizing gear (81) structure is coaxially arranged at one end of the casing, the synchronizing gear box body (8) is detachably connected with the casing, and the synchronizing gears (81) are respectively sleeved on a driving transmission shaft (61) and a driven transmission shaft (71) extending out of the casing.

4. The split rubber-lined double-screw pump according to claim 1 or 3, further comprising a reduction gear box, wherein the driving transmission shaft (61) is connected with a driving shaft (94) of the driving device through the reduction gear box, the reduction gear box comprises a reduction gear box body (9), a driving gear (92) and a driving gear (91), the driving gear (92) is sleeved on the driving shaft (94), the driving gear (91) is sleeved on the driving transmission shaft (61), the driving gear (91) is meshed with the driving gear (92), and the outer diameter of the driving gear (91) is larger than the outer diameter of the driving gear (92).

5. The split rubber-lined double-screw pump according to claim 4, wherein the housing, the synchronous gear structure, the reduction gear box and the driving device are sequentially connected, the reduction gear box (9) is connected with the synchronous gear box (8) through a coupling body (95), the other end of the housing is sequentially connected with a pump end cover plate (2) and an end cover (1), the driving transmission shaft (61) and the driven transmission shaft (71) respectively penetrate through the pump end cover (1) through a bearing (21), the end cover (1) is provided with a transmission shaft accommodating cavity (11) towards the pump end cover plate (2) for placing the ends of the driving transmission shaft (61) and the driven transmission shaft (71), the end cover (1), the pump end cover plate (2), the housing, the synchronous gear box (8), the coupling body (95) and the reduction gear box (9) are coaxially connected, the pump end cover plate (2), the shell, the synchronous gear box body (8), the connecting body (95) and the reduction gear box body (9) are connected sequentially through a flange structure.

6. The split rubber-lined double-screw pump according to claim 5, wherein flange structures are arranged at both ends of the synchronous gear (81) box, and the flange structures of the outer shell, the synchronous gear box body (8), the pump end cover plate (2) and the reduction gear box body (9) are arranged in the same specification structure.

7. The split rubber-lined twin-screw pump according to claim 1, wherein the inner surfaces of the screw receiving chamber, the water inlet (31) and the water outlet (51) are coated with a corrosion resistant material.

8. The split rubber-lined double screw pump according to claim 1, characterized in that the inner surfaces of the bushings (4) facing the driving screw transmission part (6) and the driven screw transmission part (7) are provided with bushing lining layers (44).

9. The split rubber-lined double-screw pump according to claim 1, wherein the driving screw and the driven screw comprise metal brackets and rubber layers uniformly wrapped on the metal brackets.

10. The split rubber-lined double-screw pump according to claim 9, wherein the metal bracket and the rubber layer are molded by a casting process, and a rubber layer desulfurization treatment is arranged during the casting operation.

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