Gap sealing structure in high-pressure multi-stage tandem pump set
Patent Information
- Application Number
- CN202522418220.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-14
- Publication Date
- 2026-09-18
- Estimated Expiration
- 2035-11-14
AI Technical Summary
位于串联系统中后段的泵体（压力大于1.6 MPa时），其轴封需要承受显著增高的系统压力，这可能导致密封组件在长期运行中出现泄漏量增大、磨损加快等现象
进一步地，多个导流槽的初始端处于轴向上的不同的位置，用以对密封间隙中不同轴向区段的泄漏流体进行分级引流，使得泄漏介质能够从密封间隙的不同区段被分别引出，有助于实现压力的分级释放，从而可以形成更为平缓的压力梯度，对降低局部压力峰值、改善整体密封环境具有积极意义。
Smart Images
Figure CN224770500U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of centrifugal pump technology, specifically a gap sealing structure in a high-pressure multi-stage series pump set. Background Technology
[0002] As mineral resource extraction expands into deep and ultra-deep wells, mines exceeding 1,000 meters in depth are becoming increasingly common. This trend places higher demands on drainage systems. Traditional single-unit multistage pumps often face challenges in meeting the high-lift requirements of deep wells, such as excessively large structural dimensions and difficulties in transportation and installation. Against this backdrop, solutions employing multiple pumps operating in series have gradually gained attention.
[0003] However, the multi-pump series connection scheme faces new technical challenges during implementation. When multiple pumps are connected in series, the system operating pressure accumulates progressively between each pump, posing a challenge to the reliability of the pump set's shaft sealing system. The pumps located in the later stages of the series system (when the pressure exceeds 1.6 MPa) need to withstand significantly increased system pressures, which may lead to increased leakage and accelerated wear of the sealing components during long-term operation. The decline in sealing performance not only affects the pump set's operating efficiency but may also impact the equipment's operational stability. Utility Model Content
[0004] This invention aims to solve the above-mentioned problems, thereby providing a gap sealing structure in a high-pressure multi-stage series pump set that ensures the operating efficiency of the pump set. The technical solution adopted by this utility model to solve the aforementioned problem is: A gap sealing structure for a high-pressure multi-stage series pump set includes a sealing gland for fixing to the pump body, and a bushing sleeve that is sleeved on the outside of the pump shaft and rotates with it. It also includes a sealing sleeve fixed inside the sealing gland and sleeved on the outer periphery of the bushing sleeve. A radial sealing gap is formed between the bushing sleeve and the sealing sleeve. Multiple independent guide grooves are provided axially on the outer periphery of the sealing sleeve. A drain port communicating with the sealing gap is provided on the sealing sleeve corresponding to the initial end of each guide groove. Multiple discharge holes communicating with the end of the guide groove are provided on the sealing gland.
[0005] Compared with the prior art, the outstanding features of this utility model, which adopts the above technical solution, are: By setting up a sealing sleeve structure that includes a guide groove, a drain port, and a discharge hole, the leaked medium passing through the sealing gap can be effectively guided and discharged. This structure helps to reduce the actual pressure load acting on the sealing assembly and has a positive effect on improving the working condition of the sealing assembly under high pressure conditions, thereby providing support for improving the adaptability and operational stability of the pump shaft sealing system under high pressure conditions.
[0006] As a preferred embodiment, a further technical solution of this utility model is: Furthermore, the initial ends of multiple guide grooves are located at different positions in the axial direction to divert the leakage fluid in different axial sections of the sealing gap in stages. This allows the leakage medium to be drawn out from different sections of the sealing gap separately, which helps to achieve graded pressure release and thus forms a gentler pressure gradient. This has a positive effect on reducing local pressure peaks and improving the overall sealing environment.
[0007] Furthermore, the ends of multiple diversion channels are located at the same position in the axial direction. This arrangement is conducive to collecting the leaked media drawn from different axial positions and directing them to a unified discharge area, creating conditions for subsequent centralized diversion and simplifying the layout of external diversion pipelines to a certain extent.
[0008] Furthermore, multiple partition ring grooves are spaced apart on the inner wall of the sealing sleeve, and the drain port is opened at the bottom of the partition ring groove, so that each partition ring groove constitutes an independent pressure relief unit. This structure intervenes in the leakage medium flowing through the sealing gap through the partition ring groove, and can form a series of continuous local pressure reduction areas in the axial direction of the sealing gap. Each partition ring groove and its drain port together constitute an independent pressure relief unit, which can collect and guide the fluid at its location. This method helps to establish a more refined stepped pressure distribution, which plays a positive role in achieving step-by-step pressure reduction and improving the overall pressure environment within the sealing gap.
[0009] Furthermore, the cross-sectional shape of the guide channel is rectangular. The rectangular cross-section of the guide channel is relatively convenient in terms of processing and manufacturing, and at the same time, it can provide a relatively stable flow section, which helps to maintain the smooth flow of the leaking medium and plays a positive role in maintaining the expected diversion effect.
[0010] Furthermore, the drain hole is connected to an external drain pipe, the outlet end of which is configured to connect to a drain point in the pump unit where the pressure matches the pressure at the corresponding drain port. By directing the leaking medium to a region with matching pressure, it helps to establish relatively balanced pressure conditions. This design aims to promote the smooth discharge of leaking fluid and reduce additional flow disturbances that may be caused by improper pressure differentials, which plays a positive role in maintaining the stable operation of the sealing system. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of the cross-sectional structure of the pump body according to an embodiment of the present utility model; Figure 2 for Figure 1 A magnified schematic diagram of the structure of part A in the diagram; Figure 3 This is a schematic cross-sectional view of the sealing box according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the cross-sectional structure of the sealing sleeve according to an embodiment of the present utility model; Figure 5 This is a schematic diagram of the installation structure of the external drainage pipe of the multi-stage series pump group according to an embodiment of the present utility model; The components in the diagram are labeled as follows: 1. Sealing box; 2. Shaft sleeve; 3. Sealing sleeve; 4. Guide groove; 5. Drain port; 6. Drain hole; 7. External drainage pipe; 8. Isolation ring groove. Detailed Implementation
[0012] The present invention will be further described below with reference to embodiments, the purpose of which is only to better understand the content of the present invention. Therefore, the examples given do not limit the scope of protection of the present invention.
[0013] A gap sealing structure for a high-pressure multi-stage series pump set includes a sealing gland 1 for fixing to the pump body, and a bushing 2 that is sleeved on the outside of the pump shaft and rotates therewith. It also includes a sealing sleeve 3 fixed inside the sealing gland 1 and sleeved on the outer periphery of the bushing 2. A radial sealing gap is formed between the bushing 2 and the sealing sleeve 3. Multiple independent guide grooves 4 are provided axially on the outer periphery of the sealing sleeve 3. A drain port 5 communicating with the sealing gap is provided on the sealing sleeve 3 corresponding to the initial end of each guide groove 4. Multiple discharge holes 6 communicating with the ends of the guide grooves 4 are provided on the sealing gland 1.
[0014] Furthermore, the initial ends of multiple guide grooves 4 are located at different positions in the axial direction to guide the leakage fluid in different axial sections of the sealing gap in a graded manner, so that the leakage medium can be drawn out from different sections of the sealing gap separately, which helps to achieve graded pressure release and thus can form a gentler pressure gradient, which has a positive effect on reducing local pressure peaks and improving the overall sealing environment.
[0015] Furthermore, the ends of multiple guide channels 4 are located at the same position in the axial direction. This arrangement is conducive to collecting the leakage medium drawn out from different axial positions and directing it to a unified discharge area, creating conditions for subsequent centralized drainage and simplifying the arrangement of external drainage pipes 7 to a certain extent.
[0016] Furthermore, multiple partition ring grooves 8 are spaced apart on the inner wall of the sealing sleeve 3, and the drain port 5 is opened at the bottom of the partition ring groove 8, so that each partition ring groove 8 constitutes an independent pressure relief unit. This structure intervenes in the leakage medium flowing through the sealing gap through the partition ring groove 8, and can form a series of continuous local pressure reduction areas in the axial direction of the sealing gap. Each partition ring groove 8 and the drain port inside it together constitute an independent pressure relief unit, which can collect and guide the fluid at its location. This method helps to establish a more refined stepped pressure distribution, which has a positive effect on achieving step-by-step pressure reduction and improving the overall pressure environment in the sealing gap.
[0017] Furthermore, the cross-sectional shape of the guide channel 4 is rectangular. The rectangular cross-section of the guide channel 4 is relatively convenient in terms of processing and manufacturing, and at the same time, it can provide a relatively stable flow section, which helps to maintain the smooth flow of the leaking medium and has a positive effect on maintaining the expected diversion effect.
[0018] Furthermore, the drain hole 6 is connected to an external drain pipe 7. The outlet end of the external drain pipe 7 is configured to connect to a drain point in the pump set whose pressure matches the pressure at the corresponding drain port 5. By directing the leaking medium to a region with matching pressure, it helps to establish relatively balanced pressure conditions. This design aims to promote the smooth discharge of leaking fluid and reduce additional flow disturbances that may be caused by improper pressure differential, which plays a positive role in maintaining the stable operation of the sealing system.
[0019] The system operating pressure will accumulate step by step between each pump body. When the pressure of the pump body in the later stage of the series system reaches 1.6MPa or above, this gap sealing structure is adopted to guide the leaked medium back to the relatively low pressure area in the pump group through the external drainage pipe 7. According to the actual pressure distribution in the pump group, the external drainage pipes 7 corresponding to different discharge ports 5 can be connected to drainage points with appropriate pressure. These drainage points include, but are not limited to, the inlet of the front pump, the inlet of the previous front pump, or the interstage flow channel, etc., which are low pressure locations. Through this staged drainage method, a relatively balanced pressure condition can be established to promote the smooth discharge of leaked fluid.
[0020] When the pump sets are running in series, the system pressure accumulates step by step. The shaft seal of the downstream pump body will be subjected to higher pressure (e.g., ≥1.6MPa). At this time, the leaking medium passes through the sealing gap between the shaft sleeve 2 and the sealing sleeve 3. Multiple isolation ring grooves 8 set on the inner wall of the sealing sleeve 3 first perform preliminary classification of the leaking fluid. Each isolation ring groove 8 achieves local pressure relief through the corresponding drain port 5, forming the first-level pressure step within the sealing gap. Subsequently, multiple independent guide grooves 4 set on the outer circumference of the sealing sleeve 3 with their initial ends located at different axial positions perform secondary classification and diversion of the leaking fluid in different axial sections after preliminary pressure reduction. The leaking liquid collected by each guide groove 4 flows along the groove and is finally discharged from the drain hole 6 at the end. The external drain pipe 7 connected to the drain hole 6 leads the leaking medium of different pressure levels to the drain point in the pump set with the corresponding pressure. Through this multi-stage drainage and pressure matching loop design, a complete stepped pressure drop system is formed, thereby effectively mitigating the direct impact of high pressure on the shaft seal system and improving the sealing working conditions.
[0021] The above description is only a preferred embodiment of the present utility model and does not limit the scope of the present utility model. All equivalent changes made based on the content of the present utility model specification and its drawings are included within the scope of the present utility model.
Claims
1. A gap sealing structure in a high-pressure multi-stage series pump set, comprising a sealing gland for fixing to the pump body, and a bushing sleeve fitted over the pump shaft and rotating therewith, characterized in that: It also includes a sealing sleeve fixed inside the sealing box and sleeved on the outer circumference of the bushing. A radial sealing gap is formed between the bushing and the sealing sleeve. Multiple independent guide grooves are provided on the outer circumference surface of the sealing sleeve along the axial direction. A drain port communicating with the sealing gap is provided on the sealing sleeve corresponding to the initial end of each guide groove. Multiple drain holes communicating with the end of the guide groove are opened on the sealing box.
2. The clearance seal structure in a high-pressure multi-stage series pump set according to claim 1, characterized by: The initial ends of multiple guide grooves are located at different positions in the axial direction to divert the leaking fluid in different axial sections of the sealing gap in stages.
3. The interstitial seal structure in a high pressure multi-stage in-line pump set of claim 2, wherein: The ends of multiple guide channels are located at the same position in the axial direction.
4. The interstitial seal structure in a high pressure multi-stage in-line pump set of claim 1, wherein: Multiple partition ring grooves are spaced apart on the inner wall of the sealing sleeve, and the drain port is opened at the bottom of the partition ring groove, so that each partition ring groove constitutes an independent pressure relief unit.
5. The interstitial seal structure in a high pressure multi-stage in-line pump set of claim 1, wherein: The cross-sectional shape of the guide channel is rectangular.
6. The gap sealing structure in the high-pressure multi-stage series pump set according to claim 1, characterized in that: The drain hole is connected to an external drainage pipe, and the outlet end of the external drainage pipe is configured to connect to a drainage point in the pump set whose pressure matches the pressure at the corresponding drain port.