Centrifugal disc packing seal structure for pumps

Abstract

This utility model provides a centrifugal disc packing seal structure for centrifugal pumps, comprising a rotating shaft, a shaft sleeve, centrifugal discs, a pump cover, a sealing ring, and a sealing assembly. The rotating shaft is rotatably connected to the pump body, the shaft sleeve is fitted onto the rotating shaft, and the centrifugal discs are secured to the ends of the shaft sleeve and rotate with the shaft. The pump cover is connected to the pump body, pressing against the outer circumference of the centrifugal discs, forming a sealing cavity together with the shaft sleeve and the pump body. The sealing assembly includes a water guide ring, a double-lip oil seal, packing, and a packing gland. The oil seal is located between the centrifugal discs and the water guide ring, and the packing is located between the water guide ring and the pump cover. The inner circumference of the water guide ring has a clearance fit with the shaft sleeve, and its outer circumference forms a flow channel with the pump cover, connecting the flushing inlet and flushing outlet to achieve flushing fluid circulation. It has advantages such as self-adaptability, leak prevention, good heat dissipation, and long service life, and is suitable for centrifugal pumps handling high-temperature, corrosive, or easily crystallizing media. It offers reliable sealing performance, convenient maintenance, and strong practicality.

Description

Technical Field

[0001] This utility model relates to pump sealing structures, and in particular to a centrifugal disc packing sealing structure for pumps. Background Technology

[0002] During the operation of a centrifugal pump, the sealing structure between the shaft and the pump body is crucial, directly affecting the pump's leakage control, operational safety, and service life. While traditional packing seals are simple and inexpensive, they are prone to problems such as rapid packing wear, severe leakage, and poor heat dissipation when conveying high-temperature, corrosive, or easily crystallizing media, and require frequent maintenance. Some pumps use mechanical seals, which offer good sealing performance, but their complex structure, high cost, and stringent installation precision requirements make them ineffective. Furthermore, traditional seals are insufficient to effectively prevent media leakage during pump startup or low-speed operation. Therefore, there is an urgent need for a pump sealing structure that is structurally sound, reliable, adaptable, and easy to maintain. Utility Model Content

[0003] In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide a centrifugal disc sealing junction for pumps, which solves the problem that centrifugal pumps are difficult to effectively prevent media leakage in the prior art.

[0004] To achieve the above and other related objectives, this utility model provides a centrifugal disc packing seal structure for connecting to the pump body of a centrifugal pump, comprising: a rotating shaft rotatably inserted into the pump body; a bushing sleeved on the rotating shaft; centrifugal discs sleeved on the rotating shaft and engaged at the end of the bushing; a pump cover pressing against the outer periphery of the centrifugal discs and connected to the pump body; a sealing ring sleeved on the outer periphery of the bushing sleeve and embedded in the inner cavity of the pump cover; the pump cover, centrifugal discs, bushing sleeve, and pump body together form a sealing cavity, and a sealing assembly is provided within the sealing cavity.

[0005] In one embodiment of the present invention, the sealing assembly includes a water guide ring disposed on the outer periphery of the bushing, an oil seal located between the water guide ring and the centrifugal vane, and packing and a gland disposed between the water guide ring and the pump cover.

[0006] In one embodiment of this utility model, the inner circumference of the water guide ring and the bushing are in clearance fit, and the outer circumference of the water guide ring and the pump cover are in fit to form a flow channel.

[0007] In one embodiment of the present invention, the flow channel is connected to a flushing inlet and a flushing outlet.

[0008] In one embodiment of this utility model, the centrifugal disc is annular, and its outer edge opens due to centrifugal force when the shaft rotates at high speed, tightly adhering to the inner wall of the pump cover and forming a dynamic seal.

[0009] In one embodiment of this utility model, the oil seal is a double-lip oil seal, with the inner lip of the oil seal having an interference fit with the outer circumference of the bushing, and the outer lip of the oil seal being sealed to the inner wall of the pump cover.

[0010] As described above, the centrifugal disc packing seal structure for pumps of this utility model has the following beneficial effects: The centrifugal disc packing seal structure for pumps provided by this utility model, through the multi-stage collaborative design of centrifugal discs, oil seals, water guide rings, packing, and flushing system, achieves an organic combination of dynamic and static sealing, significantly improving sealing performance and operational reliability. When the shaft rotates at high speed, the centrifugal discs automatically open due to centrifugal force, tightly adhering to the pump cover to form a dynamic sealing barrier, achieving an adaptive function of "the higher the speed, the tighter the seal," effectively reducing leakage during start-up and shutdown. The double-lip oil seal, shaft sleeve, and pump cover form a double radial seal, preventing axial leakage of the medium. The water guide ring cooperates with the pump cover to form a flow channel, and introduces external flushing fluid through the flushing inlet and outlet, achieving continuous cooling and self-cleaning of the sealing area, preventing medium crystallization or carbonization. The packing provides a stable static seal under the action of the packing gland, further enhancing sealing safety. The overall structure is compact and easy to maintain, suitable for high-temperature, corrosive, particulate, or easily crystallizing media conditions, and has good sealing performance. Attached Figure Description

[0011] Figure 1 The diagram shown is a structural schematic of this utility model.

[0012] Component designation explanation

[0013] 1. Pump body; 2. Shaft; 3. Shaft sleeve; 4. Centrifugal vane; 5. Pump cover; 6. Sealing ring; 7. Water guide ring; 8. Oil seal; 9. Packing; 10. Gland; 11. Flow guide channel; 12. Flushing inlet; 13. Flushing outlet. Detailed Implementation

[0014] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification.

[0015] Please see Figure 1 This utility model provides a centrifugal disc type sealing structure for pumps, used to connect with the pump body 1 of a centrifugal pump, including: a rotating shaft 2 rotatably inserted into the pump body 1; a bushing 3 sleeved on the rotating shaft 2; a centrifugal disc 4 sleeved on the rotating shaft 2 and clamped at the end of the bushing 3; a pump cover 5 pressing against the outer periphery of the centrifugal disc 4 and connected to the pump body 1; a sealing ring 6 sleeved on the outer periphery of the bushing 3 and embedded in the inner cavity of the pump cover 5; the pump cover 5, centrifugal disc 4, bushing 3 and pump body 1 together form a sealing cavity, and a sealing assembly is provided in the sealing cavity.

[0016] During operation, the pump employs a centrifugal vane-type packing seal structure. The rotating shaft 2 drives the shaft sleeve 3 and centrifugal vanes 4 to rotate synchronously. Since the centrifugal vanes 4 are fitted onto the end of the shaft sleeve 3 and rotate with the shaft, during high-speed rotation, the outer edge of the centrifugal vanes 4 opens outwards under centrifugal force, forming a dynamic sealing barrier against the inner wall of the pump cover 5, effectively preventing leakage of the pump medium to the outside. Simultaneously, the sealing components within the sealing cavity work together to prevent axial leakage of the medium. The guide groove on the water guide ring 7 connects to the flushing inlet 12 and outlet on the pump cover 5, introducing external flushing fluid to cool and clean the sealing area, carrying away any potentially leaked medium or impurities. The packing 9 achieves a static seal under the pressure of the packing 9 gland 10, further enhancing sealing reliability.

[0017] The sealing assembly includes a water guide ring 7 disposed on the outer periphery of the bushing 3, an oil seal 8 located between the water guide ring 7 and the centrifugal vane 4, a packing 9 disposed between the water guide ring 7 and the pump cover 5, and a gland 10.

[0018] In this structure, the sealing assembly consists of a water guide ring 7, an oil seal 8, packing 9, and a packing 9 gland 10. During operation, the oil seal 8 is positioned between the water guide ring 7 and the centrifugal vane 4. The water guide ring 7 is fitted around the outer circumference of the shaft sleeve 3, and its outer circumference cooperates with the pump cover 5 to form a flow channel 11, which guides the flow of flushing fluid or leaking media. The packing 9 is installed between the water guide ring 7 and the pump cover 5, and axial preload is applied through the packing 9 gland 10 to achieve a static seal of the sealing cavity. When the pump is running, external flushing fluid enters the flow channel 11 through the flushing inlet 12 to cool and clean the sealing area, preventing media accumulation or carbonization and ensuring long-term stable operation of the seal.

[0019] The inner circumference of the water guide ring 7 is clearance-fitted with the bushing 3, while the outer circumference of the water guide ring 7 fits with the pump cover 5 to form a flow guiding channel 11. The clearance fit between the inner circumference of the water guide ring 7 and the outer circumference of the bushing 3 allows the water guide ring 7 to smoothly fit into the bushing 3 during assembly, while maintaining a small annular gap to allow a small amount of leaked medium or flushing fluid to flow axially. The outer circumference of the water guide ring 7 is precisely fitted with the inner cavity of the pump cover 5, together forming the annular flow guiding channel 11.

[0020] The flow channel 11 is connected to a flushing inlet 12 and a flushing outlet 13. The flow channel 11 is connected to the flushing inlet 12 and the flushing outlet 13 on the pump cover 5. During pump operation, external cleaning flushing fluid enters from the flushing inlet 12, flows through the flow channel 11, carries away the heat generated in the sealing area and any particulate impurities that may accumulate, and is discharged from the flushing outlet 13, thereby achieving continuous cooling and self-cleaning of the sealing components and ensuring that the oil seal 8 and packing 9 work under suitable conditions.

[0021] The centrifugal vane 4 is annular. Its outer edge expands due to centrifugal force when the shaft 2 rotates at high speed, tightly adhering to the inner wall of the pump cover 5 and forming a dynamic seal. The centrifugal vane 4 is an annular thin-plate structure, sleeved on the end of the bushing 3 and rotating synchronously with the shaft 2. When the pump starts and the shaft 2 rotates at high speed, the outer edge of the centrifugal vane 4 expands radially outward under the action of centrifugal force, automatically adhering to the inner wall of the pump cover 5 to form a sealing surface. This sealing pressure increases with increasing rotational speed, achieving an adaptive dynamic sealing effect where "the higher the rotational speed, the tighter the seal."

[0022] The oil seal 8 is a double-lip oil seal. The inner lip of the oil seal 8 is interference-fitted with the outer circumference of the bushing 3, and the outer lip of the oil seal 8 is sealed to the inner wall of the pump cover 5. This double-lip design, with the inner lip forming an interference fit with the outer circumference of the bushing 3 and tightly covering the surface of the rotating shaft 2, constitutes a radial seal, effectively preventing the pump medium from leaking outwards axially. The outer lip maintains a tight seal contact with the inner wall of the pump cover 5, forming a static seal and blocking the path of the medium flowing around the outside of the oil seal 8.

[0023] The centrifugal disc 4-type packing 9 sealing structure for pumps provided by this utility model achieves an organic combination of dynamic and static sealing through the multi-stage collaborative design of the centrifugal disc 4, oil seal 8, water guide ring 7, packing 9, and flushing system, significantly improving sealing performance and operational reliability. When the shaft 2 rotates at high speed, the centrifugal disc 4 automatically opens due to centrifugal force, tightly adhering to the pump cover 5 to form a dynamic sealing barrier, achieving an adaptive function of "the higher the speed, the tighter the seal," effectively reducing leakage during start-up and shutdown. The double-lip oil seal 8, together with the shaft sleeve 3 and pump cover 5, forms a double radial seal, preventing axial leakage of the medium. The water guide ring 7, in conjunction with the pump cover 5, forms a flow channel 11, and introduces external flushing fluid through the flushing inlet 12 and outlet, achieving continuous cooling and self-cleaning of the sealing area, preventing medium crystallization or carbonization. The packing 9 provides a stable static seal under the action of the packing 9 gland 10, further enhancing sealing safety. The overall structure is compact and easy to maintain, suitable for high-temperature, corrosive, particulate, or easily crystallizing media conditions, and has excellent sealing performance.

[0024] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A centrifugal disc packing seal structure for pumps, used for connection to the pump body of a centrifugal pump, characterized in that, include: A rotating shaft that is rotatably inserted into the pump body; A bushing fitted onto the rotating shaft; A centrifugal disc sleeved on the rotating shaft and clamped at the end of the shaft sleeve; A pump cover that presses against the outer periphery of the centrifugal vane and is connected to the pump body; A sealing ring that is fitted around the outer circumference of the bushing and embedded in the inner cavity of the pump cover; The pump cover, centrifugal vane, shaft sleeve, and pump body together form a sealed cavity, and a sealing assembly is provided inside the sealed cavity.

2. The centrifugal disc packing seal structure for pumps according to claim 1, characterized in that: The sealing assembly includes a water guide ring disposed on the outer periphery of the bushing, an oil seal located between the water guide ring and the centrifugal vane, and packing and a gland disposed between the water guide ring and the pump cover.

3. The centrifugal disc packing seal structure for pumps according to claim 2, characterized in that: The inner circumference of the water guide ring and the bushing are fitted with a clearance, and the outer circumference of the water guide ring and the pump cover are fitted to form a flow channel.

4. The centrifugal disc packing seal structure for pumps according to claim 3, characterized in that: The flow channel is connected to a flushing inlet and a flushing outlet.

5. The centrifugal disc packing seal structure for pumps according to claim 1, characterized in that: The centrifugal disc is annular, and its outer edge opens due to centrifugal force when the shaft rotates at high speed, tightly adhering to the inner wall of the pump cover and forming a dynamic seal.

6. The centrifugal disc packing seal structure for pumps according to claim 2, characterized in that: The oil seal is a double-lip structure oil seal, with the inner lip of the oil seal having an interference fit with the outer circumference of the bushing, and the outer lip of the oil seal being sealed to the inner wall of the pump cover.

Images