Pump head of marine deep-well pump and marine deep-well pump

Abstract

The invention provides a pump head of a marine deep-well pump and the marine deep-well pump, and belongs to the technical field of ship engineering. The pump head comprises a pump shell, a pump shaft, an impeller and a sealing device, the sealing device comprises a shaft sleeve, a base and two sealing assemblies, the pump shaft is sleeved with the shaft sleeve, the shaft sleeve is connected with the pump shaft in a sealed mode, the base is located in the pump shell, the shaft sleeve is sleeved with the base, the base is connected with the pump shell in a sealed mode, and the two sealing assemblies are arranged on the base. An annular space is formed by the bearing and the shaft sleeve; each sealing assembly comprises a static sealing ring and a dynamic sealing structure, the static sealing ring is connected with the base, the dynamic sealing structure is located on the side, away from the other sealing assembly, of the static sealing ring in the sealing assembly, and the dynamic sealing structure is connected with the shaft sleeve; the dynamic sealing structure makes contact with the static sealing ring and forms a sealing face perpendicular to the axis of the shaft sleeve. The assembly process of the pump head can be simplified.

Description

Technical Field

[0001] The present disclosure belongs to the technical field of mechanical seals, and in particular relates to a pump head of a marine deep well pump and a marine deep well pump. Background Art

[0002] Marine deep-well pumps can transport liquid cargo media. These pumps consist of a cargo pipe, a pump head, and a lubricating oil pipe. The cargo pipe and lubricating oil pipe are spaced apart and connected via a flange plate. The lubricating oil pipe is connected to the pump head, which includes the pump casing, pump shaft, and impeller. One end of the pump shaft extends into the pump casing and connects to the impeller inside. The other end extends outside the pump casing and resides in the lubricating oil pipe. One end of the cargo pipe is integrated with and connected to the pump casing. The pump shaft can rotate at high speeds, driving the impeller. Once the impeller rotates, the cargo pipe transfers the liquid cargo. Because the pump shaft generates heat due to friction during rotation, causing it to heat up, it requires a good lubrication and cooling environment.

[0003] In related art, the pump head also includes two rotary shaft seals. Each rotary shaft seal includes a dynamic seal ring and a static seal ring. The dynamic seal ring is mounted on the outside of the pump shaft and located within the pump casing. An O-ring is sandwiched between the dynamic seal ring and the pump shaft to form a radial static seal. Each static seal ring is fixed within the pump casing and located outside the pump shaft, positioned between the dynamic seal rings of the two rotary shaft seals. The static seal ring contacts the dynamic seal ring and forms a sealing surface. This ensures that the lubricating oil outside the pump shaft is isolated from the liquid cargo medium inside the pump casing.

[0004] However, each component of the above rotary shaft seal needs to be assembled one by one, making the assembly process of the pump head complicated. Summary of the Invention

[0005] The present disclosure provides a pump head for a marine deep well pump and a marine deep well pump, which can simplify the assembly process of the pump head. The technical solution is as follows:

[0006] The embodiment of the present disclosure provides a pump head of a marine deep well pump, wherein the pump head comprises a pump casing, a pump shaft, an impeller and a sealing device, one end of the pump shaft is connected to the impeller and both are located in the pump casing; the sealing device comprises a shaft sleeve, a base and two sealing assemblies, the shaft sleeve is sleeved outside the pump shaft and is sealed with the pump shaft, the base is located in the pump casing and sleeved outside the shaft sleeve, the base is sealed with the pump casing and forms an annulus with the shaft sleeve; the two sealing assemblies are arranged in the annulus at intervals along the axial direction of the shaft sleeve, each of the sealing assemblies comprises a static sealing ring and a dynamic sealing structure, the static sealing ring is connected to the base, the dynamic sealing structure is located on the side of the static sealing ring in the sealing assembly away from the other sealing assembly, the dynamic sealing structure is connected to the shaft sleeve, the dynamic sealing structure contacts the static sealing ring and forms a sealing surface perpendicular to the axis of the shaft sleeve.

[0007] In another embodiment of the present disclosure, the base includes a cylinder, an inner ring plate and two pressure plates, the inner ring plate is located at one end of the cylinder and is connected to the cylinder; the two pressure plates are respectively located at opposite ends of the inner ring plate, and each of the pressure plates is connected to the inner ring plate; the two static sealing rings are arranged between the inner ring plate and the shaft sleeve along the axial direction of the cylinder, and a portion of each static sealing ring is located between the two pressure plates, and one of the pressure plates is against each other.

[0008] In another embodiment of the present disclosure, a detection cavity is provided on the outside of the pump casing, and the inner ring plate has a plurality of first channels spaced apart along its circumference, each of the first channels extends radially along the inner ring plate, one end of the first channel is connected to the space defined between the two static sealing rings, and the other end of the first channel is connected to the detection cavity through the gap between the outer peripheral wall of the inner ring plate and the inner wall of the pump casing.

[0009] In another embodiment of the present disclosure, one of the two pressure plates closer to the impeller is a first pressure plate, and the first pressure plate has a plurality of circulation holes spaced apart along its own circumference; the side wall of the cylinder has a plurality of second channels spaced apart along its own circumference, and the plurality of second channels correspond one-to-one to the plurality of circulation holes, and one end of each of the second channels is connected to the corresponding circulation hole, and the other end is connected to the outside of the cylinder.

[0010] In another embodiment of the present disclosure, the impeller is provided with a plurality of balancing holes spaced apart along its circumference near the center thereof, the balancing holes passing through both axial ends of the impeller, one end of the balancing holes being connected to the interior of the cylinder, and the other end being connected to the outside of the impeller.

[0011] In another embodiment of the present disclosure, a first gap is defined between an end surface of the cylinder away from the inner ring plate and the impeller, and a second gap is defined between the pump casing and an end of the impeller facing the inner ring plate; the base further comprises an outer ring plate, the outer ring plate being located outside an end of the cylinder away from the inner ring plate and connected to the cylinder, and the outer ring plate being connected to the pump casing; a storage cavity for accommodating a liquid cargo medium is defined between the outer ring plate and an outer wall of the cylinder, the pump casing, and the impeller, and the storage cavity is communicated with the first gap and the second gap, respectively.

[0012] In another embodiment of the present disclosure, the impeller includes a plurality of back blades and an impeller body, wherein the plurality of back blades are located on the side of the impeller body facing the base at circumferential intervals along the impeller body and are connected to the impeller body, and each of the back blades extends radially along the impeller body.

[0013] In another embodiment of the present disclosure, the dynamic sealing structure includes a bellows, a dynamic ring seat and a dynamic sealing ring. The dynamic ring seat is located at one end of the bellows facing the static sealing ring and is connected to the bellows. The dynamic sealing ring is embedded in the dynamic ring seat and partially located outside the dynamic ring seat. The dynamic sealing ring contacts the static sealing ring and forms the sealing surface.

[0014] In another embodiment of the present disclosure, the dynamic sealing structure further includes a connecting seat, which is located at an end of the bellows away from the static sealing ring and is connected to the bellows, and the connecting seat is connected to the shaft sleeve.

[0015] On the other hand, an embodiment of the present disclosure also provides a marine deep well pump, which includes a pump head, a liquid cargo pipe and a lubricating oil pipe. The liquid cargo pipe and the lubricating oil pipe are spaced apart and are both connected to the pump head. The pump head is the pump head described above.

[0016] The technical solutions provided by the embodiments of the present disclosure have the following beneficial effects:

[0017] When the sealing device provided by the embodiment of the present disclosure is used on the pump shaft of a marine deep well pump, since the base and the two sealing components are both arranged outside the shaft sleeve, and the shaft sleeve is used to be sleeved outside the pump shaft, the two sealing components can be integrated together through the shaft sleeve and the base, so that the entire sealing device can be installed by being sleeved on the outside of the pump shaft as a whole, avoiding the need to install the static sealing ring and the dynamic sealing structure in the sealing component one by one, simplifying the installation process, and greatly improving the installation efficiency.

[0018] Moreover, since the base is sealed and connected to the pump housing, when the entire sealing device is sleeved outside the pump shaft, the base can be fixed on the pump housing to achieve the fixation of the sealing device.

[0019] It can be seen that the above sealing device can be installed in an integrated manner outside the pump shaft through the arrangement of the shaft sleeve and the base, thereby improving the installation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0021] Figure 1 This is a partial structural diagram of a marine deep well pump;

[0022] Figure 2 for Figure 1 Schematic diagram of the structure of the sealing device.

[0023] The symbols in the figure mean the following:

[0024] 100. Liquid cargo pipe;

[0025] 201, pump housing; 2011, oil pipe; 203, pump shaft; 2031, double-row angular contact bearing; 2032, cylindrical roller bearing; 205, impeller; 2050, balancing hole; 2051, back blade; 2052, impeller body; 207, detection chamber; 2071, air inlet pipe; 2072, air outlet pipe; 208, pumping ring;

[0026] 1. Bushing; 101. First gap; 102. Second gap; 105. Storage chamber;

[0027] 2. Base; 21. Cylinder; 211. Second channel; 22. Inner ring plate; 220. First channel; 221. Inner flange; 23. Press plate; 231. First press plate; 2310. Flow hole; 24. Outer ring plate;

[0028] 3. Sealing assembly; 31. Static sealing ring; 311. External flange; 32. Dynamic sealing structure; 321. Bellows; 322. Dynamic ring seat; 323. Dynamic sealing ring; 324. Connecting seat. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0030] Figure 1 This is a partial structural diagram of a marine deep well pump, such as Figure 1The marine deep well pump comprises a pump head, a lubricating oil tank (not shown in the figure), a lubricating oil pipe (not shown in the figure) and a liquid cargo pipe 100.

[0031] The pump head includes a pump housing 201, a pump shaft 203, an impeller 205, and a sealing device. A liquid cargo pipe 100 is located on one side of the pump housing 201, with one end of the pipe integrally injection-molded with the pump housing 201. The pipe 100 communicates with the interior of the pump housing 201. A lubricating oil pipe is located on one side of the pipe 100, with one end connected to the pump housing 201 and the other end connected to the lubricating oil tank. The pipe and the pipe 100 are connected via multiple axially spaced flanges.

[0032] One end of the pump shaft 203 and the impeller 205 are located within the pump housing 201. The other end is located within the lubricating oil pipe and connected to the motor output through the lubricating oil tank. The impeller 205 is sleeved around and connected to the pump shaft 203. Driven by the motor, the pump shaft 203 rotates, driving the impeller 205. This rotation of the impeller 205 allows the liquid cargo pipe 100 to transport the liquid cargo medium.

[0033] Illustratively, a flat key is provided at the end of the pump shaft 203 , and the impeller 205 is connected to the pump shaft 203 via the flat key.

[0034] Continue to see Figure 1 The sealing device includes a sleeve 1, a base 2, and two sealing assemblies 3. The sleeve 1 is sleeved over the pump shaft 203 and sealed therewith. One end of the sleeve 1 abuts against the impeller 205, and the other end abuts against the shoulder of the pump shaft 203. The base 2 is located within the pump casing 201 and sleeved over the sleeve 1. The base 2 is sealed to the pump casing 201 and forms an annulus with the sleeve 1.

[0035] Two sealing assemblies 3 are arranged in the annulus at intervals along the axial direction of the sleeve 1. Each sealing assembly 3 includes a static sealing ring 31 and a dynamic sealing structure 32. The static sealing ring 31 is connected to the base 2. The dynamic sealing structure 32 is located on the side of the static sealing ring 31 in the sealing assembly 3 away from the other sealing assembly 3. The dynamic sealing structure 32 is connected to the sleeve 1. The dynamic sealing structure 32 contacts the static sealing ring 31 and forms a sealing surface perpendicular to the axis of the sleeve 1.

[0036] When the sealing device provided by the embodiment of the present disclosure is used on the pump shaft of a marine deep well pump, since the base 2 and the two sealing assemblies 3 are all arranged outside the shaft sleeve 1, and the shaft sleeve 1 is used to be sleeved outside the pump shaft 203, the two sealing assemblies 3 can be integrated together through the shaft sleeve 1, so that the entire sealing device can be installed by being sleeved as a whole outside the pump shaft 203, avoiding the need to install the static sealing ring 31 and the dynamic sealing structure 32 in the sealing assembly 3 one by one, simplifying the installation process and greatly improving the installation efficiency.

[0037] Moreover, since the base 2 is in sealing contact with and connected to the pump housing 201, when the entire sealing device is sleeved outside the pump shaft 203, the base 2 can be fixed on the pump housing 201 to achieve the fixation of the sealing device.

[0038] It can be seen that the above sealing device can be integratedly installed outside the pump shaft 203 through the arrangement of the shaft sleeve 1 and the base 2, thereby improving the installation efficiency.

[0039] In the disclosed example, the sleeve 1 is radially fitted with the pump shaft 203 , and a sealing ring is used to seal the sleeve 1 and the pump shaft 203 . One end of the sleeve 1 is inserted into the hub of the impeller 205 and is axially pressed onto the pump shaft 203 through the impeller 205 .

[0040] Continue to see Figure 1 The base 2 includes a cylinder 21, an inner ring plate 22 and two pressure plates 23. The inner ring plate 22 is sleeved outside the shaft sleeve 1 and is located at one end of the cylinder 21. The inner ring plate 22 is connected to the cylinder 21.

[0041] Two pressure plates 23 are located at opposite ends of the inner ring plate 22 and correspond one-to-one with the two static seal rings 31. Each pressure plate 23 is connected to the inner ring plate 22. The two static seal rings 31 are spaced apart along the axial direction of the cylinder 21 between the inner ring plate 22 and the shaft sleeve 1, and each static seal ring 31 is partially located between the two pressure plates 23 and abuts against one pressure plate 23.

[0042] In the above embodiment, the cylinder 21 is used to provide a mounting base for the inner ring plate 22. The inner ring plate 22 is used to provide a mounting base for two pressure plates 23, and the pressure plates 23 are used to constrain the corresponding static sealing ring 31 between the inner ring plate 22 and the corresponding dynamic sealing structure 32.

[0043] In the disclosed embodiment, the inner wall of the inner ring plate 22 has an inner flange 221. The static sealing ring 31 has an outer flange 311. The two axial end faces of the inner flange 221 correspond one-to-one to the outer flanges 311 of the two static sealing rings 31. A sealing ring is clamped between each end face of the inner flange 221 and the corresponding outer flange 311. In addition, the outer flange 311 of each static sealing ring 31 is located between the corresponding pressure plate 23 and the end face of the corresponding inner flange 221. The two pressure plates 23 are connected to the inner ring plate 22 by axially extending screws. In this way, the inner flange 221 and the outer flange 311 can be limited and installed together, and then the static sealing ring 31 can be pressed onto the base 2 through the pressure plate 23.

[0044] A sealing ring is sandwiched between the outer peripheral wall of the cylinder 21 and the pump housing 201. A sealing ring is also sandwiched between the end surface of the inner ring plate 22 away from the cylinder 21 and the pump housing 201. In this way, the lubricating oil and the liquid cargo medium can be sealed respectively.

[0045] Illustratively, the sealing rings mentioned in the embodiments of the present disclosure may all be O-rings.

[0046] Optionally, a detection chamber 207 is provided outside the pump housing 201 , and an air inlet pipe 2071 and an air outlet pipe 2072 communicating with the outside are provided in the detection chamber 207 .

[0047] The inner ring plate 22 has a plurality of first channels 220 spaced apart along its circumference. Each first channel 220 extends radially along the inner ring plate 22. One end of each first channel 220 communicates with the space defined between the two static seal rings 31. The other end of each first channel 220 communicates with the detection chamber 207 through the gap between the outer circumferential wall of the inner ring plate 22 and the inner wall of the pump housing 201. Part of each first channel 220 is located within the inner flange 221.

[0048] In the above implementation, the first channel 220 is provided to connect the lubrication space outside the pump shaft 203 with the detection chamber 207. In this way, the sealing effect of the sealing device outside the pump shaft 203 can be tested by ventilating the interior of the detection chamber 207.

[0049] For example, during the assembly of the pump head, the sealing device is tested for sealing by connecting the pump pressure device through the air inlet pipe 2071. During the test, high-pressure gas is introduced into the air inlet pipe 2071, and the high-pressure gas enters the detection chamber 207 through the air inlet pipe 2071, and enters the space where the two sealing surfaces outside the sleeve 1 are located through the first channel 220. After maintaining the pressure for a period of time, the sealing performance of the sealing device can be tested by testing the air pressure at the air outlet pipe 2072. If the air pressure at the air outlet pipe 2072 is lower than the air pressure in the air inlet pipe 2071, the sealing device is leaking. If the air pressure at the air outlet pipe 2072 is the same as the air pressure in the air inlet pipe 2071, the sealing performance of the sealing device is good.

[0050] Before and after the normal unloading operation of the chemical tanker and during the transportation of the ship, the leakage of the sealing device can also be checked by purging, so as to facilitate the timely maintenance of the sealing device. For example, during the inspection, a high-pressure gas with a pressure of about 4 Bar is introduced into the air inlet pipe 2071, and the high-pressure gas enters the detection chamber 207 through the air inlet pipe 2071. If there is lubricating oil or liquid cargo medium remaining in the detection chamber 207, the lubricating oil or liquid cargo medium will be blown by the air flow of the high-pressure gas and discharged from the air outlet pipe 2072 along with the air flow. That is, by regularly purging the detection chamber 207 and checking whether there is lubricating oil or liquid cargo medium discharged from the air outlet pipe 2072, it can be determined whether there is a leak in the sealing device. If lubricating oil or liquid cargo medium is found to be discharged from the air outlet pipe 2072, the sealing performance of the sealing device is not good. If no lubricating oil or liquid cargo medium is found to be discharged from the air outlet pipe 2072, the sealing performance of the sealing device is good.

[0051] The detection chamber 207 is used for seal leakage monitoring, which can completely eliminate the risk of cross contamination.

[0052] Optionally, the one of the two pressure plates 23 facing the impeller 205 is a first pressure plate 231 , and the first pressure plate 231 has a plurality of flow holes 2310 distributed at intervals along its circumference.

[0053] The side wall of the cylinder 21 has a plurality of second channels 211 distributed along its own circumference, and the plurality of second channels 211 correspond one-to-one to the plurality of flow holes 2310, and one end of each second channel 211 is connected to the corresponding flow hole 2310, and the other end is connected to the outside of the cylinder 21.

[0054] In the above implementation, since the flow hole 2310 is connected to the second channel 211, the liquid medium at the impeller 205 can enter the space where the sealing device is located along the second channel 211 and the flow hole 2310. As a result, the introduced liquid medium forms a liquid film between the sealing surfaces of the sealing device, which plays a lubricating role, reduces friction and wear between the end faces, and at the same time can reduce the temperature of the sealing device and extend the service life of the sealing device.

[0055] Optionally, impeller 205 is provided with a plurality of balancing holes 2050 spaced apart along its circumference near its center. Balancing holes 2050 extend through both axial ends of impeller 205, and along the axis of sleeve 1, the projections of balancing holes 2050 on base 2 are all located within cylinder 21. One end of balancing hole 2050 communicates with the interior of cylinder 21, and the other end communicates with the exterior of impeller 205.

[0056] In the above implementation, when the liquid cargo medium enters the space where the sealing device is located along the second channel 211 and the flow hole 2310, the liquid cargo medium can flush the sealing component 3 located at Figure 1 The sealing surface (i.e., friction surface) between the dynamic seal structure 32 and the static seal ring 31 below removes impurities and dirt, keeping the sealing surface clean. The introduced liquid medium forms a liquid film between the sealing surfaces, providing lubrication and reducing friction and wear between the end faces. The liquid medium is then discharged through the balancing hole 2050, forming a circulation system that continuously removes heat generated by friction between the dynamic seal structure 32 and the static seal ring 31, reducing the temperature of the seal assembly 3 and extending its service life.

[0057] Optionally, a first gap 101 is defined between an end surface of the cylinder 21 away from the inner ring plate 22 and the impeller 205 , and a second gap 102 is defined between the pump casing 201 and an end of the impeller 205 facing the inner ring plate 22 .

[0058] The base 2 also includes an outer ring plate 24, which is located outside the end of the cylinder 21 away from the inner ring plate 22 and is connected to the cylinder 21. The outer ring plate 24 is connected to the pump casing 201. A storage cavity 105 for accommodating the liquid cargo medium is defined between the outer ring plate 24, the outer wall of the cylinder 21, the pump casing 201, and the impeller 205. The storage cavity 105 is connected to the first gap 101 and the second gap 102, respectively.

[0059] The arrangement of the outer ring plate 24 forms a storage cavity 105 , which facilitates better collection of the liquid cargo medium, thereby introducing the liquid cargo medium into the lower sealing surface through the second channel 211 .

[0060] The arrangement of the first gap 101 and the second gap 102 can make the liquid cargo medium at the impeller 205 pass through the blade gap of the impeller 205 and then enter the space where the sealing device is located along the second gap 102, the second channel 211 and the flow hole 2310, thereby Figure 1 Flush the sealing device on the lower middle side.

[0061] In this embodiment, in order to further enhance the self-cleaning effect of the liquid medium on the lower sealing assembly 3, the width of the first gap 101 (ie Figure 1 The spacing d1) is not greater than the second gap 102 (ie Figure 1 This allows more liquid cargo medium to enter the second channel 211 from the second gap 102 to clean the lower sealing component 3.

[0062] Exemplarily, the width of the second gap 102 is not less than 0.5 mm.

[0063] In this embodiment, the outer ring plate 24 is fixed to the pump housing 201 by screws.

[0064] In this embodiment, the above structure can enable the lower sealing surface to achieve a self-flushing function, ensuring that the temperature rise of the lower sealing surface is controlled within 35° C., and extending the service life of the sealing device to over 12,000 hours.

[0065] Optionally, the impeller 205 includes a plurality of back blades 2051 and an impeller body 2052. The plurality of back blades 2051 are located at intervals along the circumference of the impeller body 2052 on a side of the impeller body 2052 facing the base 2 (i.e., the back side) and are connected to the impeller body 2052. Each back blade 2051 extends radially of the impeller body 2052. A first gap 101 is formed between the back blades 2051 and the cylinder 21.

[0066] In this way, when the back blades 2051 rotate along with the impeller body 2052, the overall axial force of the impeller 205 is reduced, the wear between the sealing surfaces is reduced, and the service life of the sealing device is extended. At the same time, the back blades 2051 can also guide the liquid medium to flow from the outside of the hub of the impeller body 2052 to the outer edge of the impeller body 2052, thereby allowing the liquid medium to enter the second gap 102 smoothly.

[0067] For example, the back blades 2051 are ribbed. This not only significantly improves the impeller's bending and torsional rigidity, preventing blade deformation, but also creates a rear pump cavity between the back of the impeller 205 and the pump housing 201, balancing the back cavity pressure and reducing the axial force generated by the impeller 205, thereby extending the service life of the sealing device. Excessive axial force can exacerbate wear on the sealing surface.

[0068] Optionally, a double row angular contact bearing 2031 and a cylindrical roller bearing 2032 are connected to the central outer shell of the pump shaft 203. The double row angular contact bearing 2031 and the cylindrical roller bearing 2032 are both located on the same side of the sealing device, and the cylindrical roller bearing 2032 is located between the sealing device and the double row angular contact bearing 2031.

[0069] The pump shaft 203 is supported within the pump housing 201 by a double-row angular contact bearing 2031 and a cylindrical roller bearing 2032. This prevents overloading of any single bearing and extends the overall life of the pump. Furthermore, the cylindrical roller bearing 2032 bears the primary radial load, while the double-row angular contact bearing 2031 absorbs bidirectional axial forces and some radial forces, while also providing axial positioning.

[0070] Moreover, the double row angular contact bearing 2031 and the cylindrical roller bearing 2032 are lubricated with lubricating oil, and both the double row angular contact bearing 2031 and the cylindrical roller bearing 2032 are immersed in the lubricating oil.

[0071] Optionally, an oil pipe 2011 is connected to the sidewall of the pump housing 201. One end of the oil pipe 2011 passes through the sidewall of the pump housing 201 and is located within the pump housing 201, between the cylindrical roller bearing 2032 and a seal assembly 3 adjacent to the cylindrical roller bearing 2032. This allows lubricating oil to be introduced through the oil pipe 2011, allowing the exterior of the pump shaft 203 to be cooled and lubricated by the lubricating oil. Furthermore, the lubricating oil is blocked by the two seal assemblies 3, preventing it from mixing with the liquid cargo medium at the impeller 205.

[0072] Optionally, the pump head further includes a pumping ring 208, which is located between the double-row angular contact bearing 2031 and the cylindrical roller bearing 2032 and is sleeved outside the pump shaft 203. The pumping ring 208 is connected to the pump shaft 203 and has a spiral structure along the axis of the pump shaft 203.

[0073] As the pumping ring 208 rotates along with the pump shaft 203, the rotation of the spiral structure drives the lubricating oil to generate relative motion within the thread groove, creating a pressure differential that drives the lubricating oil to circulate through the oil pipe 2011. Simultaneously, the pumped lubricating oil directly flushes the sealing surface between the upper dynamic seal structure 32 and the static seal ring 31, removing impurities in the lubricating oil and heat generated by the sealing surface between the upper dynamic seal structure 32 and the static seal ring 31, thereby reducing the temperature of the sealing assembly and extending the service life of the sealing assembly.

[0074] In addition, in order to maintain the cleanliness of the lubricating oil, a filter is provided at the inlet end of the oil pipe 2011 (an end outside the pump housing 201). After the lubricating oil passes through the filter, the filter can filter out the abrasive particles generated during the operation of the pump shaft 203, thereby maintaining the cleanliness of the lubricating oil.

[0075] In this embodiment, the pumping ring 208 and the pump shaft 203 are integrally formed. That is, the pumping ring 208 is directly machined during the production of the pump shaft 203. This enhances the secure connection between the two. Furthermore, the design of the pumping ring 208 keeps the temperature rise of the upper sealing surface below 35°C, extending the service life of the sealing device to over 12,000 hours.

[0076] Figure 2 for Figure 1 Schematic diagram of the structure of the sealing device, combined with Figure 2 Optionally, the dynamic sealing structure 32 includes a bellows 321 , a dynamic ring seat 322 and a dynamic sealing ring 323 . The dynamic ring seat 322 is located at one end of the bellows 321 facing the static sealing ring 31 and is connected to the bellows 321 .

[0077] The dynamic sealing ring 323 is embedded in the dynamic ring seat 322 and partially located outside the dynamic ring seat 322 . The dynamic sealing ring 323 contacts the static sealing ring 31 to form a sealing surface.

[0078] In the above implementation, the dynamic ring seat 322 provides a mounting base for the dynamic sealing ring 323. The dynamic sealing ring 323 forms a sealing surface with the static sealing ring 31. The bellows 321 supports the dynamic sealing ring 323. At the same time, the elastic deformation of the bellows 321 continuously pushes the dynamic sealing ring 323 against the static sealing ring 31, compensating for wear on the sealing surface and extending its service life. Furthermore, the bellows 321 can absorb small axial and radial displacements (e.g., ±0.5 mm), preventing the sealing surface from separating due to vibration or shaft swing.

[0079] In this embodiment, the bellows 321 is a stainless steel bellows, which allows the bellows 321 to be exposed to high temperature environments (e.g., 200° C. to 800° C.) and withstand higher pressures (e.g., above 30 MPa), thereby improving the applicability of the sealing device.

[0080] Optionally, the dynamic sealing structure 32 further includes a connecting seat 324 . The connecting seat 324 is located at one end of the bellows 321 away from the static sealing ring 31 and is connected to the bellows 321 . The connecting seat 324 is connected to the shaft sleeve 1 .

[0081] In the above implementation, the connecting seat 324 is used to fix the dynamic sealing structure 32 on the shaft sleeve 1 so as to rotate along with the shaft sleeve 1 and the pump shaft 203 .

[0082] The connecting seat 324 is fixed to the shaft sleeve 1 by means of a set screw. To improve sealing, a sealing ring (such as an O-ring) is sandwiched between the connecting seat 324 and the shaft sleeve 1. A sealing ring (such as an O-ring) is also sandwiched between the shaft sleeve 1 and the pump shaft 203.

[0083] In the disclosed embodiment, the dynamic sealing structure 32 adopts laser welding 316L stainless steel bellows (wall thickness 0.2mm±0.01mm) integrated molding technology, and the axial length of the two-stage sealing assembly is compressed through topological optimization design, which greatly reduces the installation space compared with the traditional spring compensation structure.

[0084] On the other hand, an embodiment of the present disclosure also provides a marine deep well pump, which includes a pump head, a liquid cargo pipe and a lubricating oil pipe. The liquid cargo pipe and the lubricating oil pipe are separated and both are connected to the pump head, which is the pump head mentioned above.

[0085] The above-mentioned marine deep well pump has the same beneficial effects as the aforementioned pump head, which will not be described in detail here.

[0086] The working process of the pump head provided by the embodiment of the present disclosure is described below:

[0087] First, two sealing assemblies 3 are installed between the base 2 and the shaft sleeve 1 at intervals, and the dynamic sealing ring 323 of each sealing assembly 3 is connected to the shaft sleeve 1, and the static sealing ring 31 of each sealing assembly 3 is connected to the base 2.

[0088] Then, the entire sealing device is sleeved on the pump shaft 203 through the shaft sleeve 1, and the base 2 is connected to the pump housing 201. In this way, the sealing device can be installed.

[0089] During operation, the two sealing surfaces formed by the two sealing assemblies 3 seal the lubricating oil and the liquid cargo medium, respectively. Simultaneously, the detection cavity 207 can be used to monitor seal leakage, facilitating subsequent and timely mechanical seal maintenance. The upper sealing assembly 3 effectively flushes the sealing surface via the pumping ring 208 on the pump shaft 203, preventing overheating. The lower sealing assembly 3 utilizes the pressure differential generated by the back vanes 2051 and balancing holes 2050 to achieve self-flushing, allowing the liquid cargo medium to effectively flush the sealing surface and prevent overheating.

[0090] The pump head provided in the disclosed embodiments utilizes an integrated sealing device to physically isolate the lubricating oil on the pump shaft 203 from the liquid cargo medium, ensuring the long-term, stable operation of the marine deep-well pump under complex media conditions. Furthermore, by providing a modular assembly design for the sealing device, assembly and disassembly time is greatly reduced, and the clearance between the sealing surfaces within the sealing device can be adjusted without specialized tooling.

[0091] The above description is merely an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. A pump head for a marine deep well pump, characterized in that: The pump head comprises a pump housing (201), a pump shaft (203), an impeller (205) and a sealing device, wherein one end of the pump shaft (203) is connected to the impeller (205) and both are located in the pump housing (201); The sealing device comprises a shaft sleeve (1), a base (2) and two sealing assemblies (3); the shaft sleeve (1) is sleeved outside the pump shaft (203) and is sealed with the pump shaft (203); the base (2) is located inside the pump housing (201) and sleeved outside the shaft sleeve (1); the base (2) is sealed with the pump housing (201) and forms an annulus with the shaft sleeve (1); The two sealing assemblies (3) are arranged in the annulus at intervals along the axial direction of the shaft sleeve (1); each of the sealing assemblies (3) comprises a static sealing ring (31) and a dynamic sealing structure (32); the static sealing ring (31) is connected to the base (2); the dynamic sealing structure (32) is located on the side of the static sealing ring (31) in the sealing assembly (3) away from the other sealing assembly (3); the dynamic sealing structure (32) is connected to the shaft sleeve (1); the dynamic sealing structure (32) contacts the static sealing ring (31) and forms a sealing surface perpendicular to the axis of the shaft sleeve (1).

2. The pump head according to claim 1, characterized in that The base (2) comprises a cylinder (21), an inner ring plate (22) and two pressure plates (23), wherein the inner ring plate (22) is located at one end of the cylinder (21) and is connected to the cylinder (21); The two pressing plates (23) are respectively located at opposite ends of the inner ring plate (22), and each pressing plate (23) is connected to the inner ring plate (22); The two static sealing rings (31) are arranged between the inner ring plate (22) and the shaft sleeve (1) at intervals along the axial direction of the cylinder (21), and a portion of each static sealing ring (31) is located between the two pressure plates (23) and abuts against one of the pressure plates (23).

3. The pump head according to claim 2, characterized in that A detection cavity (207) is provided on the outside of the pump housing (201), and the inner ring plate (22) has a plurality of first channels (220) spaced apart along its circumference, each of the first channels (220) extending radially along the inner ring plate (22), one end of the first channel (220) communicating with the space defined between the two static sealing rings (31), and the other end of the first channel (220) communicating with the detection cavity (207) through a gap between the outer peripheral wall of the inner ring plate (22) and the inner wall of the pump housing (201).

4. The pump head according to claim 2, characterized in that Of the two pressure plates (23), the one closer to the impeller (205) is a first pressure plate (231), and the first pressure plate (231) has a plurality of flow holes (2310) spaced apart along its circumference. The side wall of the cylinder (21) has a plurality of second channels (211) distributed at intervals along its own circumference, and the plurality of second channels (211) correspond one-to-one to the plurality of circulation holes (2310), and one end of each second channel (211) is connected to the corresponding circulation hole (2310), and the other end is connected to the outside of the cylinder (21).

5. The pump head according to claim 4, characterized in that The impeller (205) is provided with a plurality of balancing holes (2050) spaced apart along its circumference near the center thereof, the balancing holes (2050) passing through both ends of the axial direction of the impeller (205), one end of the balancing hole (2050) is connected to the interior of the cylinder (21), and the other end is connected to the exterior of the impeller (205).

6. The pump head according to claim 5, characterized in that A first gap (101) is formed between an end surface of the cylinder (21) away from the inner ring plate (22) and the impeller (205), and a second gap (102) is formed between the pump housing (201) and an end of the impeller (205) facing the inner ring plate (22); The base (2) further comprises an outer ring plate (24), the outer ring plate (24) being located outside one end of the cylinder (21) away from the inner ring plate (22) and connected to the cylinder (21), and the outer ring plate (24) being connected to the pump housing (201); A storage cavity (105) for accommodating a liquid medium is defined between the outer ring plate (24), the outer wall of the cylinder (21), the pump casing (201), and the impeller (205), and the storage cavity (105) is communicated with the first gap (101) and the second gap (102), respectively.

7. The pump head according to claim 5, characterized in that The impeller (205) includes a plurality of back blades (2051) and an impeller body (2052), wherein the plurality of back blades (2051) are located on a side of the impeller body (2052) facing the base (2) at circumferential intervals along the impeller body (2052) and are connected to the impeller body (2052), and each of the back blades (2051) extends radially along the impeller body (2052).

8. The pump head according to any one of claims 1 to 7, characterized in that The dynamic sealing structure (32) comprises a bellows (321), a dynamic ring seat (322) and a dynamic sealing ring (323), wherein the dynamic ring seat (322) is located at one end of the bellows (321) facing the static sealing ring (31) and is connected to the bellows (321); The dynamic sealing ring (323) is embedded in the dynamic ring seat (322) and is partially located outside the dynamic ring seat (322). The dynamic sealing ring (323) contacts the static sealing ring (31) and forms the sealing surface.

9. The pump head according to claim 8, characterized in that The dynamic sealing structure (32) further includes a connecting seat (324), which is located at one end of the bellows (321) away from the static sealing ring (31) and is connected to the bellows (321), and the connecting seat (324) is connected to the shaft sleeve (1).

10. A deep well pump for marine use, characterized in that: The marine deep well pump comprises a pump head, a liquid cargo pipe and a lubricating oil pipe. The liquid cargo pipe and the lubricating oil pipe are spaced apart and are both connected to the pump head. The pump head is the pump head according to any one of claims 1 to 9.

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