Anti-corrosion centrifugal pump with packaging type double-end-face mechanical seal

Abstract

The utility model relates to an anti-corrosion centrifugal pump with a packaging type double-end-face mechanical seal. A movable ring seat of the mechanical seal is made of a non-metal material; a main shaft anti-corrosion sheath and a limiting pressing and fixing ring are arranged at an axial gap between the mechanical seal and an impeller of the pump machine; a sealing structure is arranged between an inner hole of the movable ring seat and the main shaft anti-corrosion sheath; the sealing structure is at least one sheath sealing ring. The main shaft anti-corrosion sheath has the beneficial effects that the main shaft anti-corrosion sheath solves the anti-corrosion protection problem of the axial clearance on the main shaft; the sheath sealing ring has high radial deformation performance, and can also have good sealing performance when the non-metal moving ring seat with high plasticity of mechanical sealing generates micro thermal deformation; the problem that the sealing performance is reduced as a new leakage point is generated at an axial gap due to thermal deformation of the non-metal moving ring seat can be avoided; the designed lining plastic type or all-plastic type anti-corrosion centrifugal pump has excellent anti-corrosion performance, and after the lining plastic type or all-plastic type anti-corrosion centrifugal pump is matched with a packaging type double-end-face mechanical seal, most corrosive media can be conveyed.

Description

Technical Field

[0001] This utility model belongs to the field of mechanical seal technology, and in particular relates to a corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal. Background Technology

[0002] In current production processes of new energy battery materials, hydrochloric acid and hydrofluoric acid are present in many operating conditions. However, the components of double-end mechanical seals on the market are made of stainless steel. Since stainless steel is not resistant to corrosion from media containing chloride and fluoride ions, these corrosion-resistant pumps with stainless steel double-end mechanical seals cannot safely transport media containing chloride and fluoride ions. If corrosion-resistant centrifugal pumps with stainless steel double-end mechanical seals continue to be used in the production processes of new energy battery materials, the production processes of new energy and new materials cannot be met.

[0003] The dynamic ring of the mechanical seal cannot be directly fixed to the base of the impeller; otherwise, it would be difficult to install and fix the mounting plate of the cartridge mechanical seal to the pump casing. Therefore, a certain axial installation distance must be left between the double-end mechanical seal and the pump impeller to form an axial clearance. However, the existence of this axial clearance will cause the corrosive liquid being transported to leak into the corrosion protection of the main shaft.

[0004] After the spindle protection adopts a non-metallic mechanical seal, the corrosion protection requirements are increased. Using a stainless steel anti-corrosion sleeve no longer meets the sealing requirements of the axial clearance. If the sleeve of the spindle installation gap section is made of ceramic or plastic material, the strength is insufficient and it is not feasible. Therefore, the problem of corrosion protection of the axial clearance on the spindle needs to be solved.

[0005] In existing technology, the rotating ring seat of a mechanical seal is made of stainless steel, which has good rigidity and prevents thermal deformation of the sealing components. For cartridge-type mechanical seals, O-rings are used to prevent external leakage between the rotating ring seat and the spindle. To improve the corrosion resistance of the mechanical seal, the original mechanical seal components have been modified to be made of non-metallic materials. However, the rotating ring seat of a non-metallic mechanical seal is also made of non-metallic material, which has a large coefficient of thermal deformation and is prone to deformation. If the original O-rings are still used as the external leakage prevention method between the cartridge-type mechanical seal and the spindle, new leakage points will appear at the axial clearance, reducing the sealing effect. In summary, although the corrosion resistance of the mechanical seal has been improved, the static sealing performance between the mechanical seal and the shaft has decreased, therefore further improvements are needed. Utility Model Content

[0006] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal.

[0007] This corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal includes a main shaft, shaft seal, pump casing, impeller, impeller cap, pump cover, bearing bracket, bearing, side cover, coupling, motor, and mounting base; the shaft seal is a mechanical seal; the mechanical seal includes a seal box, shaft sleeve, rotating ring, rotating ring seat, stationary ring, stationary ring seat, spring, cooling water seal assembly, and positioning buckle; the seal box is equipped with a cooling water inlet and a cooling water outlet;

[0008] The bushing and the rotating ring seat are integrally molded;

[0009] The dynamic ring seat of the mechanical seal is made of non-metallic material, which overcomes the problem that the existing stainless steel cartridge double-end mechanical seal cannot safely transport media containing chloride and fluoride ions, and improves the corrosion resistance of the mechanical seal pump.

[0010] A main shaft anti-corrosion sleeve is installed at the axial clearance between the mechanical seal and the pump impeller, which solves the problem of corrosion protection of the axial clearance on the main shaft;

[0011] The rotating ring seat of the mechanical seal has an internal hole on the inner wall of the rotating ring seat on the side near the spindle. However, due to the large thermal deformation coefficient of the non-metallic rotating ring seat, the internal hole of the rotating ring seat is prone to deformation, which in turn affects the axial sealing performance of this part. Therefore, a cavity is required between the internal hole of the rotating ring seat and the anti-corrosion sleeve of the spindle. The cavity is used to install the sealing structure. The sealing structure is at least one sleeve sealing ring.

[0012] Preferably, the sealing structure is a sheath sealing ring, and the sheath sealing ring is an O-ring.

[0013] Preferably, a limiting and pressing ring is also provided on the base side of the O-ring near the impeller. The pressure that compresses the limiting and pressing ring comes from the impeller end. The limiting and pressing ring presses against and compresses the O-ring, causing the O-ring to expand radially, preventing the fluid being transported in the pump cavity at this part from leaking out through the gap between the mechanical seal moving ring seat and the main shaft anti-corrosion sleeve.

[0014] As a preferred option, the sealing structure consists of two sheathed sealing rings, both of which are O-rings. The rear O-ring pushes against the front O-ring, causing the front O-ring to expand radially and thus enhance the sealing effect.

[0015] Preferably, the O-ring near the impeller has a limiting and pressing ring on the base side of the impeller. The pressure that presses the limiting and pressing ring comes from the impeller end. The limiting and pressing ring presses against and compresses the O-ring, causing the O-ring to expand radially, preventing the fluid being pumped in this part of the pump cavity from leaking out through the gap between the mechanical seal moving ring seat and the main shaft anti-corrosion sleeve.

[0016] Preferably, the sealing structure consists of two sheathed sealing rings. The sheathed sealing ring furthest from the impeller is an O-ring, and the sheathed sealing ring closest to the impeller is a V-ring. The V-ring is also provided with a limiting and pressing ring on the base side near the impeller. The pressure that compresses the limiting and pressing ring comes from the impeller end. The limiting and pressing ring presses against and compresses the V-ring, causing the V-ring to expand radially, preventing the fluid being pumped in this part of the pump cavity from leaking out through the gap between the mechanical seal moving ring seat and the anti-corrosion sleeve of the main shaft.

[0017] Preferably, the sealing structure consists of two sheathed sealing rings. The sheathed sealing ring furthest from the impeller is an O-ring, while the sheathed sealing ring closest to the impeller is a skirted sealing ring. The skirted sealing ring also has a limiting and pressing ring on the base side near the impeller. The pressure that compresses the limiting and pressing ring comes from the impeller end. The purpose of setting the skirted sealing ring is to use the pressure of the fluid in the pump chamber to back-press the skirt of the sealing ring, so that the sealing ring can generate self-sealing ability, thereby improving the anti-leakage performance between the main shaft anti-corrosion sleeve and the mechanical seal moving ring seat.

[0018] Preferably, the sealing structure consists of two sheathed sealing rings. The sheathed sealing ring furthest from the impeller is an O-ring, while the sheathed sealing ring closest to the impeller is a skirted sealing ring. The skirted sealing ring has an axial concave-convex ring on its skirt, and the rotating ring seat has a rotating ring seat convex ring or a rotating ring seat concave ring that matches the shape of the axial concave-convex ring. The axial concave ring of the skirted sealing ring is fastened to the rotating ring seat convex ring on the rotating ring seat, or the axial convex ring of the skirted sealing ring is fastened to the rotating ring seat concave ring on the rotating ring seat. This further enhances the sealing performance of the skirted sealing ring and significantly improves the sealing performance between the pump's main shaft anti-corrosion sleeve and the mechanical seal rotating ring seat.

[0019] As a preferred option:

[0020] The moving ring is fitted onto the moving ring seat; or the moving ring is sleeve-shaped, with the moving ring enclosing the outer periphery of the moving ring seat.

[0021] The corrosion-resistant centrifugal pump is either a front-suction centrifugal pump with the suction inlet in the axial direction or a side-suction centrifugal pump with the suction inlet on the side of the shaft.

[0022] One end of the spindle anti-corrosion sleeve extends radially outward into an L-shaped flange.

[0023] As a preferred option:

[0024] The flow-through components of the corrosion-resistant centrifugal pump are made of plastic or ceramic.

[0025] The impeller, pump cover, and pump casing are all made of steel-lined ultra-high molecular weight polyethylene, or the impeller, pump cover, and pump casing are all made of plastic.

[0026] The sealed box is made of plastic, metal, or resin.

[0027] The moving ring seat is made of polytetrafluoroethylene propylene, and the bushing is made of 304 stainless steel.

[0028] Both the moving ring and the stationary ring are made of silicon carbide.

[0029] The sheath sealing ring is a rubber sealing ring, a fluoroplastic sealing ring, or a sealing ring with a plastic layer lining a rubber outer surface;

[0030] The limiting compression ring is made of a metal or non-metal material with a certain hardness. The width of the limiting compression ring is determined by the distance between the sheath sealing ring and the impeller base. During pump installation, the axial thrust of the limiting compression ring is adjusted by adjusting the axial installation position of the impeller.

[0031] The beneficial effects of this utility model are:

[0032] This utility model provides a main shaft anti-corrosion sleeve in the axial clearance portion between the dynamic ring seat of the double-end mechanical seal and the pump impeller, thus solving the problem of corrosion protection of the axial clearance on the main shaft.

[0033] A sheath seal and a limiting compression ring are installed between the rotating ring seat and the main shaft of the double-end mechanical seal. The sheath seal is one or more seals. The sheath seal has high radial deformation performance and can maintain good sealing performance even when the non-metallic rotating ring seat with high plasticity of the mechanical seal undergoes slight thermal deformation. It can avoid the problem of new leakage points at the axial clearance caused by thermal deformation of the non-metallic rotating ring seat, which would lead to a decrease in sealing performance.

[0034] This invention improves the safety of the shaft seal of the anti-corrosion centrifugal pump, enabling the shaft seal to adapt to the conveying of media containing chloride and fluoride ions, and avoids corrosion by the media. This invention designs an anti-corrosion centrifugal pump with a high anti-corrosion level, good anti-corrosion performance of the main shaft, and good anti-external leakage performance of the shaft clearance.

[0035] The skirted sealing ring is made of flexible rubber or plastic. The lined or all-plastic anti-corrosion centrifugal pump designed in this utility model has excellent anti-corrosion performance. When equipped with a cartridge-type double-end mechanical seal, it can transport most corrosive media. Attached Figure Description

[0036] Figure 1 A schematic diagram of the anti-corrosion sleeve for the main shaft at the axial clearance between the cartridge double-end mechanical seal and the pump impeller;

[0037] Figure 2 A schematic diagram of the sealing structure between the cartridge-type double-end face mechanical seal ring seat and the main shaft;

[0038] Figure 3 Schematic diagram of the sealing ring of the sleeve at the internal hole of the moving ring seat;

[0039] Figure 4Schematic diagram of the sheath sealing ring and the limiting compression ring at the internal hole of the moving ring seat;

[0040] Figure 5 A schematic diagram showing the combination of an O-ring and a V-ring at the internal hole of the moving ring seat;

[0041] Figure 6 A schematic diagram of a sealing ring with a skirt at the internal hole of the moving ring seat;

[0042] Figure 7 A schematic diagram of the convex ring of the moving ring seat and the axial concave and convex rings of the sealing ring with skirt;

[0043] Figure 8 A schematic diagram of the concave ring of the moving ring seat and the axial concave and convex rings on the sealing ring with skirt;

[0044] Figure 9 This is a schematic diagram of a centrifugal pump with a cartridge-type double-end mechanical seal.

[0045] Explanation of reference numerals in the attached drawings: 1. Main shaft; 2. Mechanical seal; 3. Rotating ring; 4. Rotating ring seat; 5. Axial clearance; 6. Main shaft anti-corrosion sleeve; 7. Impeller; 8. Stationary ring; 10. Sleeve sealing ring; 11. O-ring seal; 12. Skirted sealing ring; 13. Internal hole of rotating ring seat; 14. Inner wall of rotating ring seat; 15. Limiting and pressing ring; 16. Rotating ring seat convex ring; 17. Axial concave-convex ring; 18. Rotating ring seat concave ring; 19. Shaft sleeve; 20. Sealing box; 21. Spring; 22. Stationary ring seat; 23. Cooling water sealing assembly; 24. Cooling water inlet; 25. Cooling water outlet; 26. Positioning buckle; 27. Impeller cap; 28. Pump cover; 29. ​​Pump casing; 30. Shaft seal; 31. Bearing bracket; 32. Bearing; 33. Side cover; 34. Coupling; 35. Motor; 36. Mounting base; 37. Detailed Implementation

[0046] The present invention will be further described below with reference to embodiments. The description of the embodiments below is only for the purpose of helping to understand the present invention. It should be noted that, for those skilled in the art, several modifications can be made to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0047] Example 1

[0048] like Figure 9As shown, a corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal is a front-suction centrifugal pump with the suction inlet in the axial direction. It includes a main shaft 1, shaft seal 31, pump casing 30, impeller 7, impeller cap 28, pump cover 29, bearing bracket 32, bearing 33, side cover 34, coupling 35, motor 36, and mounting base 37. The shaft seal 31 is a mechanical seal 2. The mechanical seal 2 includes a sealing box 21, shaft sleeve 20, rotating ring 3, rotating ring seat 4, stationary ring 8, stationary ring seat 23, spring 22, cooling water sealing assembly 24, and positioning buckle 27. The sealing box 21 is provided with a cooling water inlet 25 and a cooling water outlet 26.

[0049] The flow parts of the corrosion-resistant centrifugal pump are made of plastic; the impeller 7, pump cover 29 and pump casing 30 are all made of steel-lined ultra-high molecular weight polyethylene; the sealing box 21 is made of plastic; the moving ring seat 4 is made of polytetrafluoroethylene propylene; the shaft sleeve 20 is made of 304 stainless steel; the moving ring 3 and the stationary ring 8 are both made of silicon carbide.

[0050] The bushing 20 and the rotating ring seat 4 are integrally formed, and the rotating ring 3 is embedded in the rotating ring seat 4;

[0051] The rotating ring seat 4 of the mechanical seal 2 is made of non-metallic material, which overcomes the problem that the existing stainless steel cartridge double-end mechanical seal cannot safely transport media containing chloride and fluoride ions, and improves the corrosion resistance of the mechanical seal pump.

[0052] A main shaft anti-corrosion sleeve 6 is provided at the axial clearance 5 between the mechanical seal 2 and the impeller 7 of the pump, which solves the problem of corrosion protection of the axial clearance on the main shaft. One end of the main shaft anti-corrosion sleeve 6 extends radially outward into an L-shaped flange.

[0053] The rotating ring seat 4 of the mechanical seal 2 has an internal hole 14 on the inner wall 15 of the rotating ring seat 4 near the main shaft 1. However, due to the large thermal deformation coefficient of the non-metallic rotating ring seat, the internal hole of the rotating ring seat is easily deformed, thus affecting the axial sealing performance of this part. Therefore, a cavity needs to be provided between the internal hole 14 of the rotating ring seat and the anti-corrosion sleeve 6 of the main shaft. The cavity is used to install the sealing structure. Figure 1 As shown, the sealing structure is a sheath sealing ring 10, which is an O-ring 11. The O-ring 11 is made of rubber. A limiting and pressing ring 16 is also provided on the base side of the O-ring 11 near the impeller 7. The pressure of pressing the limiting and pressing ring comes from the impeller end. The limiting and pressing ring presses against and compresses the O-ring, causing the O-ring to expand radially, preventing the fluid being transported in the pump cavity from leaking out through the gap between the mechanical seal moving ring seat and the anti-corrosion sleeve of the main shaft.

[0054] Example 2

[0055] like Figure 9As shown, a corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal is a side-suction centrifugal pump with the suction inlet on the shaft side. It includes a main shaft 1, shaft seal 31, pump casing 30, impeller 7, impeller cap 28, pump cover 29, bearing bracket 32, bearing 33, side cover 34, coupling 35, motor 36, and mounting base 37. The shaft seal 31 is a mechanical seal 2. The mechanical seal 2 includes a sealing box 21, shaft sleeve 20, rotating ring 3, rotating ring seat 4, stationary ring 8, stationary ring seat 23, spring 22, cooling water sealing assembly 24, and positioning buckle 27. The sealing box 21 is provided with a cooling water inlet 25 and a cooling water outlet 26.

[0056] The flow parts of the corrosion-resistant centrifugal pump are made of ceramic; the impeller 7, pump cover 29 and pump casing 30 are all made of plastic; the sealing box 21 is made of metal; the rotating ring seat 4 is made of polytetrafluoroethylene propylene, the shaft sleeve 20 is made of 304 stainless steel; the rotating ring 3 and the stationary ring 8 are both made of silicon carbide.

[0057] The bushing 20 and the rotating ring seat 4 are integrally formed, and the rotating ring 3 is sleeve-shaped, with the rotating ring 3 covering the outer periphery of the rotating ring seat 4;

[0058] The rotating ring seat 4 of the mechanical seal 2 is made of non-metallic material, which overcomes the problem that the existing stainless steel cartridge double-end mechanical seal cannot safely transport media containing chloride and fluoride ions, and improves the corrosion resistance of the mechanical seal pump.

[0059] A main shaft anti-corrosion sleeve 6 is provided at the axial clearance 5 between the mechanical seal 2 and the impeller 7 of the pump, which solves the problem of corrosion protection of the axial clearance on the main shaft. One end of the main shaft anti-corrosion sleeve 6 extends radially outward into an L-shaped flange.

[0060] The rotating ring seat 4 of the mechanical seal 2 has an internal hole 14 on the inner wall 15 of the rotating ring seat 4 near the main shaft 1. However, due to the large thermal deformation coefficient of the non-metallic rotating ring seat, the internal hole of the rotating ring seat is easily deformed, thus affecting the axial sealing performance of this part. Therefore, a cavity needs to be provided between the internal hole 14 of the rotating ring seat and the anti-corrosion sleeve 6 of the main shaft. The cavity is used to install the sealing structure. Figure 2 and Figure 3 As shown, the sealing structure consists of two sheathed sealing rings 10, both of which are O-rings 11. The rear O-ring pushes against the front O-ring, causing the front O-ring to expand radially and thus enhance the sealing effect.

[0061] More complete, such as Figure 4As shown, the O-ring 11 is a fluoroplastic seal ring; the O-ring 11 adjacent to the impeller 7 also has a limiting compression ring 16 on the base side of the impeller 7. The pressure of the limiting compression ring comes from the impeller end. The limiting compression ring presses against and compresses the O-ring, causing the O-ring to expand radially, preventing the fluid being pumped in this part of the pump cavity from leaking out through the gap between the mechanical seal moving ring seat and the main shaft anti-corrosion sleeve; the limiting compression ring 16 is made of a metal material with a certain hardness; the width of the limiting compression ring 16 is determined by the distance between the sleeve seal ring 10 and the base of the impeller 7. During pump installation, the axial thrust of the limiting compression ring is adjusted by adjusting the axial installation position of the impeller.

[0062] Example 3

[0063] like Figure 9 As shown, a corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal is a front-suction centrifugal pump with the suction inlet in the axial direction. It includes a main shaft 1, shaft seal 31, pump casing 30, impeller 7, impeller cap 28, pump cover 29, bearing bracket 32, bearing 33, side cover 34, coupling 35, motor 36, and mounting base 37. The shaft seal 31 is a mechanical seal 2. The mechanical seal 2 includes a sealing box 21, shaft sleeve 20, rotating ring 3, rotating ring seat 4, stationary ring 8, stationary ring seat 23, spring 22, cooling water sealing assembly 24, and positioning buckle 27. The sealing box 21 is provided with a cooling water inlet 25 and a cooling water outlet 26.

[0064] The flow parts of the corrosion-resistant centrifugal pump are made of plastic; the impeller 7, pump cover 29 and pump casing 30 are all made of steel-lined ultra-high molecular weight polyethylene; the sealing box 21 is made of resin; the moving ring seat 4 is made of polytetrafluoroethylene propylene; the shaft sleeve 20 is made of 304 stainless steel; the moving ring 3 and the stationary ring 8 are both made of silicon carbide.

[0065] The bushing 20 and the rotating ring seat 4 are integrally formed, and the rotating ring 3 is embedded in the rotating ring seat 4;

[0066] The rotating ring seat 4 of the mechanical seal 2 is made of non-metallic material, which overcomes the problem that the existing stainless steel cartridge double-end mechanical seal cannot safely transport media containing chloride and fluoride ions, and improves the corrosion resistance of the mechanical seal pump.

[0067] A main shaft anti-corrosion sleeve 6 is provided at the axial clearance 5 between the mechanical seal 2 and the impeller 7 of the pump, which solves the problem of corrosion protection of the axial clearance on the main shaft. One end of the main shaft anti-corrosion sleeve 6 extends radially outward into an L-shaped flange.

[0068] The rotating ring seat 4 of the mechanical seal 2 has an internal hole 14 on the inner wall 15 of the rotating ring seat 4 near the main shaft 1. However, due to the large thermal deformation coefficient of the non-metallic rotating ring seat, the internal hole of the rotating ring seat is easily deformed, thus affecting the axial sealing performance of this part. Therefore, a cavity needs to be provided between the internal hole 14 of the rotating ring seat and the anti-corrosion sleeve 6 of the main shaft. The cavity is used to install the sealing structure. Figure 5 As shown, the sealing structure consists of two sheathed sealing rings 10. The sheathed sealing ring 10 furthest from the impeller 7 is an O-ring 11, and the sheathed sealing ring 10 closest to the impeller 7 is a V-ring 13. The V-ring 13 is also provided with a limiting and pressing ring 16 on the base side near the impeller 7. The pressure that compresses the limiting and pressing ring comes from the impeller end. The limiting and pressing ring presses against and compresses the V-ring, causing the V-ring to expand radially, preventing the fluid being pumped in this part of the pump cavity from leaking out through the gap between the mechanical seal moving ring seat and the main shaft anti-corrosion sleeve. Both the O-ring 11 and the V-ring 13 are made of rubber with a plastic lining.

[0069] Example 4

[0070] like Figure 9 As shown, a corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal is a side-suction centrifugal pump with the suction inlet on the shaft side. It includes a main shaft 1, shaft seal 31, pump casing 30, impeller 7, impeller cap 28, pump cover 29, bearing bracket 32, bearing 33, side cover 34, coupling 35, motor 36, and mounting base 37. The shaft seal 31 is a mechanical seal 2. The mechanical seal 2 includes a sealing box 21, shaft sleeve 20, rotating ring 3, rotating ring seat 4, stationary ring 8, stationary ring seat 23, spring 22, cooling water sealing assembly 24, and positioning buckle 27. The sealing box 21 is provided with a cooling water inlet 25 and a cooling water outlet 26.

[0071] The flow parts of the corrosion-resistant centrifugal pump are made of ceramic; the impeller 7, pump cover 29 and pump casing 30 are all made of plastic; the sealing box 21 is made of metal; the rotating ring seat 4 is made of polytetrafluoroethylene propylene, the shaft sleeve 20 is made of 304 stainless steel; the rotating ring 3 and the stationary ring 8 are both made of silicon carbide.

[0072] The bushing 20 and the rotating ring seat 4 are integrally formed, and the rotating ring 3 is sleeve-shaped, with the rotating ring 3 covering the outer periphery of the rotating ring seat 4;

[0073] The rotating ring seat 4 of the mechanical seal 2 is made of non-metallic material, which overcomes the problem that the existing stainless steel cartridge double-end mechanical seal cannot safely transport media containing chloride and fluoride ions, and improves the corrosion resistance of the mechanical seal pump.

[0074] A main shaft anti-corrosion sleeve 6 is provided at the axial clearance 5 between the mechanical seal 2 and the impeller 7 of the pump, which solves the problem of corrosion protection of the axial clearance on the main shaft. One end of the main shaft anti-corrosion sleeve 6 extends radially outward into an L-shaped flange.

[0075] The rotating ring seat 4 of the mechanical seal 2 has an internal hole 14 on the inner wall 15 of the rotating ring seat 4 near the main shaft 1. However, due to the large thermal deformation coefficient of the non-metallic rotating ring seat, the internal hole of the rotating ring seat is easily deformed, thus affecting the axial sealing performance of this part. Therefore, a cavity needs to be provided between the internal hole 14 of the rotating ring seat and the anti-corrosion sleeve 6 of the main shaft. The cavity is used to install the sealing structure. Figure 6 As shown, the sealing structure consists of two sheathed sealing rings 10. The sheathed sealing ring 10 furthest from the impeller 7 is an O-ring 11, while the sheathed sealing ring 10 closest to the impeller 7 is a skirted sealing ring 12. A limiting and pressing ring 16 is also provided on the side of the skirted sealing ring 12 near the base of the impeller 7. The pressure for pressing the limiting and pressing ring comes from the impeller end. The purpose of providing the skirted sealing ring is to utilize the pressure of the fluid inside the pump chamber to back-press the skirt of the sealing ring, enabling the sealing ring to generate self-sealing capability, thereby improving the anti-leakage performance between the main shaft anti-corrosion sleeve and the mechanical seal moving ring seat. The limiting and pressing ring 16 is made of a non-metallic material with a certain degree of hardness. The width of the limiting and pressing ring 16 is determined by the distance between the sheathed sealing ring 10 and the base of the impeller 7. During pump installation, the axial thrust of the limiting and pressing ring is adjusted by adjusting the axial installation position of the impeller.

[0076] Example 5

[0077] like Figure 9 As shown, a corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal is a front-suction centrifugal pump with the suction inlet in the axial direction. It includes a main shaft 1, shaft seal 31, pump casing 30, impeller 7, impeller cap 28, pump cover 29, bearing bracket 32, bearing 33, side cover 34, coupling 35, motor 36, and mounting base 37. The shaft seal 31 is a mechanical seal 2. The mechanical seal 2 includes a sealing box 21, shaft sleeve 20, rotating ring 3, rotating ring seat 4, stationary ring 8, stationary ring seat 23, spring 22, cooling water sealing assembly 24, and positioning buckle 27. The sealing box 21 is provided with a cooling water inlet 25 and a cooling water outlet 26.

[0078] The flow parts of the corrosion-resistant centrifugal pump are made of plastic; the impeller 7, pump cover 29 and pump casing 30 are all made of steel-lined ultra-high molecular weight polyethylene; the sealing box 21 is made of plastic; the moving ring seat 4 is made of polytetrafluoroethylene propylene; the shaft sleeve 20 is made of 304 stainless steel; the moving ring 3 and the stationary ring 8 are both made of silicon carbide.

[0079] The bushing 20 and the rotating ring seat 4 are integrally formed, and the rotating ring 3 is embedded in the rotating ring seat 4;

[0080] The rotating ring seat 4 of the mechanical seal 2 is made of non-metallic material, which overcomes the problem that the existing stainless steel cartridge double-end mechanical seal cannot safely transport media containing chloride and fluoride ions, and improves the corrosion resistance of the mechanical seal pump.

[0081] A main shaft anti-corrosion sleeve 6 is provided at the axial clearance 5 between the mechanical seal 2 and the impeller 7 of the pump, which solves the problem of corrosion protection of the axial clearance on the main shaft. One end of the main shaft anti-corrosion sleeve 6 extends radially outward into an L-shaped flange.

[0082] The rotating ring seat 4 of the mechanical seal 2 has an internal hole 14 on the inner wall 15 of the rotating ring seat 4 near the main shaft 1. However, due to the large thermal deformation coefficient of the non-metallic rotating ring seat, the internal hole of the rotating ring seat is easily deformed, thus affecting the axial sealing performance of this part. Therefore, a cavity needs to be provided between the internal hole 14 of the rotating ring seat and the anti-corrosion sleeve 6 of the main shaft. The cavity is used to install the sealing structure. Figure 7 and Figure 8 As shown, the sealing structure consists of two sheathed sealing rings 10. The sheathed sealing ring 10 furthest from the impeller 7 is an O-ring 11, and the sheathed sealing ring 10 closest to the impeller 7 is a skirted sealing ring 12. The skirted sealing ring 12 has an axial concave-convex ring 18 on its skirt side. The rotating ring seat 4 has a rotating ring seat convex ring 17 or a rotating ring seat concave ring 19 that matches the shape of the axial concave-convex ring 18. The axial concave ring of the skirted sealing ring 12 is fastened to the rotating ring seat convex ring 17 on the rotating ring seat 4, or the axial convex ring of the skirted sealing ring 12 is fastened to the rotating ring seat concave ring 19 on the rotating ring seat 4. This can further improve the sealing performance of the skirted sealing ring and greatly improve the sealing performance between the pump's main shaft anti-corrosion sleeve and the mechanical seal rotating ring seat.

[0083] For embodiments 1 to 5 above, after each component is manufactured, the anti-corrosion pump can be assembled in sequence. First, the mechanical seal's dynamic and static ring seal box, spring cooling water seal assembly, and shaft sleeve of the drive ring seat are assembled together to obtain a cartridge mechanical seal made of non-metallic materials. Then, the pump components: pump casing, main shaft, impeller, pump cover, mechanical seal, main shaft anti-corrosion sleeve, and O-ring are assembled together. The installation requirements for other components of the pump are no different from the original technology, and can be installed according to the conventional installation requirements for anti-corrosion pumps. When installing the shaft clearance seal, the O-ring is inserted into the gap between the plastic dynamic ring seat of the mechanical seal and the main shaft anti-corrosion sleeve. After installation, the impeller, impeller cap, pump cover coupling, pump, mounting base, and motor are installed in sequence. After debugging, painting, and packaging, the main shaft anti-corrosion sleeve of this utility model is obtained. The inner layer is made of metal material and the outer layer is made of fluoroplastic. It has the strength of steel and can withstand axial force, as well as the anti-corrosion properties of plastic. It can prevent strong corrosive media such as hydrochloric acid and hydrofluoric acid from corroding the main shaft, resulting in a corrosion-resistant centrifugal pump with good anti-corrosion performance.

Claims

1. A corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal, comprising a main shaft (1), a shaft seal (31), a pump casing (30), an impeller (7), an impeller cap (28), a pump cover (29), a bearing bracket (32), a bearing (33), a side cover (34), a coupling (35), a motor (36), and a mounting base (37); the shaft seal (31) is a mechanical seal (2); the mechanical seal (2) comprises a sealing box (21), a shaft sleeve (20), a rotating ring (3), a rotating ring seat (4), a stationary ring (8), a stationary ring seat (23), a spring (22), a cooling water sealing assembly (24), and a positioning buckle (27); the sealing box (21) is provided with a cooling water inlet (25) and a cooling water outlet (26); characterized in that: The bushing (20) and the moving ring seat (4) are integrally formed; The rotating ring seat (4) of the mechanical seal (2) is made of non-metallic material; A main shaft anti-corrosion sleeve (6) is provided at the axial clearance (5) between the mechanical seal (2) and the impeller (7) of the pump. The rotating ring seat (4) of the mechanical seal (2) has an internal hole (14) on the inner wall (15) of the rotating ring seat on the side close to the main shaft (1); a cavity is provided between the internal hole (14) of the rotating ring seat and the anti-corrosion sleeve (6) of the main shaft, and the cavity is used to install the sealing structure; the sealing structure is at least one sleeve sealing ring (10).

2. The corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal according to claim 1, characterized in that: The sealing structure is a sheath sealing ring (10), and the sheath sealing ring (10) is an O-ring (11).

3. The corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal according to claim 2, characterized in that: The O-ring (11) is also provided with a limiting pressure ring (16) on the base side of the impeller (7).

4. The corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal according to claim 1, characterized in that: The sealing structure consists of two sheathed sealing rings (10), both of which are O-rings (11), with the rear O-ring pushing against the front O-ring.

5. The corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal according to claim 4, characterized in that: The O-ring (11) near the impeller (7) is also provided with a limiting pressure ring (16) on the base side of the impeller (7).

6. The corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal according to claim 1, characterized in that: The sealing structure consists of two sheath sealing rings (10). The sheath sealing ring (10) away from the impeller (7) is an O-ring (11), and the sheath sealing ring (10) close to the impeller (7) is a V-ring (13). The V-ring (13) is also provided with a limiting pressure ring (16) on the base side of the impeller (7).

7. The corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal according to claim 1, characterized in that: The sealing structure consists of two sheath sealing rings (10). The sheath sealing ring (10) away from the impeller (7) is an O-ring (11), and the sheath sealing ring (10) close to the impeller (7) is a skirted sealing ring (12). The skirted sealing ring (12) is also provided with a limiting pressure ring (16) on the base side of the impeller (7).

8. The corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal according to claim 1, characterized in that: The sealing structure consists of two sheathed sealing rings (10). The sheathed sealing ring (10) away from the impeller (7) is an O-ring (11), and the sheathed sealing ring (10) close to the impeller (7) is a skirted sealing ring (12). The skirted sealing ring (12) has an axial concave-convex ring (18) on its skirt side. The moving ring seat (4) has a moving ring seat convex ring (17) or a moving ring seat concave ring (19) that matches the shape of the axial concave-convex ring (18). The axial concave ring of the skirted sealing ring (12) is fastened to the moving ring seat convex ring (17) on the moving ring seat (4), or the axial convex ring of the skirted sealing ring (12) is fastened to the moving ring seat concave ring (19) on the moving ring seat (4).

9. The corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal according to claim 1, characterized in that: The moving ring (3) is fitted onto the moving ring seat (4); or the moving ring (3) is sleeve-shaped, with the moving ring (3) covering the outer periphery of the moving ring seat (4); The corrosion-resistant centrifugal pump is either a front-suction centrifugal pump with the suction inlet in the axial direction or a side-suction centrifugal pump with the suction inlet on the side of the shaft. One end of the spindle anti-corrosion sleeve (6) extends radially outward into an L-shaped flange.

10. The corrosion-resistant centrifugal pump with a cartridge-type double-end mechanical seal according to any one of claims 1, 3, 5, 6, and 7, characterized in that: The flow-through components of the corrosion-resistant centrifugal pump are made of plastic or ceramic. The impeller (7), pump cover (29) and pump casing (30) are all made of steel-lined ultra-high molecular weight polyethylene, or the impeller (7), pump cover (29) and pump casing (30) are all made of plastic. The sealed box (21) is made of plastic, metal or resin; The moving ring seat (4) is made of polytetrafluoroethylene propylene, and the bushing (20) is made of 304 stainless steel; Both the moving ring (3) and the stationary ring (8) are made of silicon carbide. The sheath sealing ring (10) is a rubber sealing ring, a fluoroplastic sealing ring, or a sealing ring with a plastic layer lining a rubber outer surface; The limiting compression ring (16) is made of a metal or non-metal material with a certain hardness; the width of the limiting compression ring (16) is determined by the distance between the sheath sealing ring (10) and the base of the impeller (7).

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