Vertical coaxial double impeller self-priming pump with integrated liquid ring vacuum wheel

Abstract

This invention discloses a vertical coaxial dual-impeller self-priming pump with an integrated liquid ring vacuum wheel, comprising: a housing, a drive motor, a vertical main shaft, and a pump body assembly. The drive motor is connected to the vertical main shaft. The pump body assembly includes a liquid ring vacuum wheel and a centrifugal pump impeller coaxially assembled and arranged from top to bottom along the vertical main shaft. The housing contains an eccentric chamber for accommodating the liquid ring vacuum wheel and a centrifugal chamber for accommodating the centrifugal pump impeller, with the eccentric chamber and the centrifugal chamber connected by an air passage. The central axis of the eccentric chamber is eccentrically positioned relative to the axis of the vertical main shaft, and a liquid storage tank is located within the eccentric chamber. The liquid ring vacuum wheel is divided into an upper liquid ring forming section and a lower water intake section by an axial separator. The liquid ring forming section is equipped with a suspension structure, and the water intake section is equipped with a water intake structure, which is placed within the liquid storage tank. This invention features a compact structure and can replace traditional long-shaft submersible pumps in situ, reducing modification costs. It eliminates the need for repeated priming and has strong self-priming stability. The segmented design of the vacuum wheel effectively reduces the overall operating power consumption.

Description

Technical Field

[0001] This invention relates to the field of self-priming pump technology, and more specifically, to a vertical coaxial double impeller self-priming pump. Background Technology

[0002] In the field of chemical hazardous materials, traditional vertical long-shaft submersible pumps have long been used for conveying Class A and B flammable and explosive media. These pumps rely on the lubrication and support of the medium through the multi-sleeve bushing of the long shaft. Impurities and crystals in the medium can easily cause wear on the bushing, leading to rotor sway, dry friction of the main shaft, and sparks. This can easily induce flash explosions and fires, posing a significant inherent safety hazard. In response, the Ministry of Emergency Management issued a document in 2025 that explicitly prohibits the use of traditional vertical long-shaft submersible pumps for conveying Class A and B flammable and explosive media. The industry urgently needs compliant alternative pump types.

[0003] Currently, the industry mainly uses conventional vertical self-priming pumps as replacement equipment. However, the existing self-priming pump structure design has obvious technical defects and cannot meet the usage requirements of safe, energy-saving, and convenient replacement of hazardous chemical media. On the one hand, conventional self-priming pumps do not have a built-in integrated vacuum priming structure. During operation, they must be equipped with an external long suction pipe to achieve negative pressure self-priming. The overall pipeline structure is complex and has low integration. Not only is the installation and modification workload large and the old pump body cannot be replaced in situ, but the external suction pipe is also prone to blockage and air leakage, leading to self-priming failure, air accumulation in the pump chamber, and dry friction leakage of the seal, resulting in poor operational reliability.

[0004] On the other hand, existing self-priming pumps with liquid ring vacuum impellers mostly adopt an integrated vacuum impeller structure without functional segment design. The integrated impeller rotates at high speed, and the entire impeller blade is immersed in and agitated by the medium throughout the process. This results in large ineffective liquid disturbance, extremely high liquid resistance loss, high overall energy consumption, and poor operating economy.

[0005] Therefore, there is an urgent need for a vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel to solve the technical pain points of existing self-priming pumps that rely on external suction pipes, are difficult to modify, and have high operating energy consumption, so as to meet the requirements of safe and compliant, energy-saving and efficient, and in-situ replacement for the transportation of Class A and B flammable and explosive hazardous media. Summary of the Invention

[0006] The purpose of this invention is to provide a vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum impeller. The main objective is to eliminate the need for an external long suction pipe through the integrated coaxial double impeller structure, resulting in a compact structure that can replace traditional long-shaft submersible pumps in situ, reducing modification costs. It eliminates the need for repeated priming and provides strong self-priming stability. At the same time, the segmented vacuum impeller structure distinguishes between the water intake and liquid ring forming functional areas, reducing media agitation losses and overall power consumption, and improving the stability of liquid ring forming.

[0007] To achieve the above objectives, the present invention provides the following solution: This invention provides a vertical coaxial dual-impeller self-priming pump with an integrated liquid ring vacuum wheel, comprising: a housing, a drive motor, a vertical main shaft, and a pump body assembly. The drive motor is connected to the vertical main shaft. The pump body assembly includes a liquid ring vacuum wheel and a centrifugal pump impeller coaxially assembled and arranged from top to bottom along the vertical main shaft. The housing contains an eccentric chamber for accommodating the liquid ring vacuum wheel and a centrifugal chamber for accommodating the centrifugal pump impeller, respectively. The eccentric chamber and the centrifugal chamber are connected by an air passage. The central axis of the eccentric chamber is eccentrically positioned relative to the axis of the vertical main shaft, and a liquid storage tank for storing a medium is formed within the eccentric chamber. The liquid ring vacuum wheel is divided into an upper liquid ring forming section and a lower water intake section by an axial separator. The liquid ring forming section is provided with a suspension structure, and the water intake section is provided with a water intake structure, which is placed within the liquid storage tank.

[0008] Preferably, the suspension structure is configured as arc-shaped protrusions evenly arranged along the circumference of the wheel body; the concave surface of the arc-shaped protrusions faces the rotation direction of the main shaft; the water intake structure is configured as continuous spiral blades, and the blade segments of the spiral blades are arranged axially in sequence along the axis.

[0009] Preferably, the axial separator is an annular partition, and the annular partition has the same outer diameter as the liquid ring forming section.

[0010] Preferably, the centrifugal pump is provided with a first air inlet channel, and the low-pressure suction zone in the eccentric chamber is provided with a second air inlet channel and an overflow channel. The first air inlet channel and the second air inlet channel are connected in an air passage. An air inlet hole is opened at the hub of the suspension structure, and the air inlet hole is connected in an air passage to the second air inlet channel. The opening of the overflow channel is flush with the bottom end face of the axial separator. The overflow channel and the air inlet hole are respectively connected to a guide pipe provided on the outside of the housing, and the guide pipe extends to the equipment pit.

[0011] Preferably, the system further includes a bearing housing, which is divided into an upper oil reservoir and a lower oil reservoir. The upper and lower oil reservoirs are located at the upper and lower ends of the radial bearing, respectively, and are in liquid communication with each other. An oil supply pipeline connecting the upper and lower oil reservoirs is provided on the outside of the housing. The oil supply pipeline is provided with an oil replenishment port and a valve body, which is used to control the opening and closing of the oil supply pipeline. An oil supply ring is provided at the bottom of the lower oil reservoir. The oil supply ring is sleeved on the outer circumference of the vertical spindle, and a spiral guide groove is provided on the oil supply ring. When the vertical spindle rotates, the spiral guide groove transports the lubricating medium in the lower oil reservoir to the oil supply pipeline.

[0012] Preferably, a heat-insulating cavity is provided between the eccentric chamber and the lower oil chamber.

[0013] Preferably, a first thrust ring is assembled between the lower oil chamber and the heat insulation chamber, and a second thrust ring is assembled between the heat insulation chamber and the eccentric chamber. The first and second thrust rings are coaxially sleeved on the outer periphery of the vertical spindle. Spiral guide grooves are formed on the surface of both the first and second thrust rings. When the vertical spindle rotates, the spiral guide grooves apply a downward axial thrust to the upward-moving medium, inhibiting the upward leakage of the medium.

[0014] Preferably, it further includes a sealing and isolation component, which is a mechanical seal fixed to the bottom of the lower oil storage chamber.

[0015] Preferably, the pump body assembly is provided with a liquid inlet suction pipe located at the bottom end of the centrifugal pump impeller, and the liquid inlet suction pipe adopts any one of the three structures of bottom liquid inlet, side liquid inlet, or top liquid inlet.

[0016] Preferably, the liquid ring vacuum wheel is made of any one of aluminum alloy, copper alloy, or high-strength non-metallic antistatic material.

[0017] The present invention achieves the following technical effects compared to the prior art: This invention employs a coaxial dual-impeller integrated structure, where the liquid ring vacuum impeller and centrifugal pump impeller operate synchronously and their chambers are interconnected. It can autonomously complete air extraction and media pressurization and delivery, eliminating the need for external long suction pipes and independent vacuum equipment. The structure is compact and can replace traditional long-shaft submersible pumps in situ, reducing modification costs. It also avoids the risk of dry friction in the pump chamber due to gas accumulation, making it suitable for the safe delivery of flammable and explosive media. The eccentrically arranged chambers, combined with the built-in liquid storage tank, can stably form a liquid ring and establish negative pressure, ensuring no liquid loss during shutdown and eliminating the need for repeated pump priming. It exhibits strong self-priming stability. Furthermore, the liquid ring vacuum impeller uses an axially segmented structure, separating the water intake and liquid ring forming functions. This avoids the high loss defects of integrated impellers that agitate the entire liquid flow, effectively reducing overall power consumption. The liquid ring forming is uniform and stable, allowing the equipment to be continuously transported under conditions containing impurities and crystalline hazardous chemicals, ensuring high operational reliability. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A cross-sectional view of a vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel; Figure 2 This is a front view of the liquid ring vacuum wheel; Figure 3 This is a cross-sectional view of the liquid ring vacuum wheel; Figure 4 This is a top view of the liquid ring vacuum wheel; Figure 5 This is a schematic diagram of gas flow during vacuuming by the liquid ring vacuum wheel; Figure 6 This is a temperature curve diagram of the heat insulation cavity and the vertical spindle.

[0020] Explanation of reference numerals in the attached drawings: 1. Housing; 2. Drive motor; 3. Vertical spindle; 4. Liquid ring vacuum wheel; 4-1. Suspension structure; 4-2. Water intake structure; 5. Centrifugal pump impeller; 5-1. First air inlet; 6. Eccentric chamber; 6-1. Second air inlet; 6-2. Overflow channel; 6-3. Air inlet; 7. Centrifugal chamber; 8. Liquid storage tank; 9. Axial separator; 10. Upper oil storage chamber; 11. Lower oil storage chamber; 11-1. Oil delivery ring; 12. Oil delivery pipeline; 13. Oil replenishment port; 14. Valve body; 15. Heat insulation chamber; 16. First thrust ring; 17. Second thrust ring; 18. Mechanical seal; 19. Liquid inlet suction pipe. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] like Figure 1-4As shown, this invention discloses a vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel, comprising: a housing 1, a drive motor 2, a vertical main shaft 3, and a pump body assembly. The drive motor 2 is connected to the vertical main shaft 3. The pump body assembly includes a liquid ring vacuum wheel 4 and a centrifugal pump impeller 5 coaxially assembled and arranged from top to bottom along the vertical main shaft 3. The housing 1 has an eccentric chamber 6 for accommodating the liquid ring vacuum wheel 4 and a centrifugal chamber for accommodating the centrifugal pump impeller 5, respectively formed therein. Chamber 7, the eccentric chamber 6 is connected to the centrifugal chamber 7 by air passage; the central axis of the eccentric chamber 6 is eccentrically arranged with respect to the axis of the vertical spindle 3, and a liquid storage tank 8 for storing the medium is formed in the eccentric chamber 6; the liquid ring vacuum wheel 4 is divided into an upper liquid ring forming section and a lower water intake section by an axial separator 9; the liquid ring forming section is provided with a suspension structure 4-1, and the water intake section is provided with a water intake structure 4-2, which is placed in the liquid storage tank 8.

[0024] By setting up a coaxial fixed structure for the two impellers, the liquid ring vacuum wheel 4 and the centrifugal pump impeller 5 rotate at completely synchronized speeds, and the air passage inside the cavity is unobstructed. The upper liquid ring vacuum wheel 4 can actively extract air from the pump cavity before the centrifugal pump impeller 5 establishes its head. The gas-liquid mixture can directly flow downwards into the centrifugal cavity to complete pressurized delivery. This completely eliminates the structure of traditional self-priming pumps that require an independent external long suction pipe and external vacuum auxiliary equipment. It can autonomously complete exhaust and self-priming by relying on the coaxial integrated air extraction of the machine. The whole machine has no extra external piping structure, and its shape and installation interface can be matched with traditional vertical long-shaft submersible pumps, achieving in-situ replacement without modification. An eccentric cavity is adopted. The central axis of chamber 6 is eccentrically positioned relative to the vertical main shaft 3. The eccentric structure of the chamber causes the gap between the liquid ring vacuum wheel 4 and the chamber to change periodically when the wheel rotates. This continuously squeezes and flings the medium inside the chamber, thereby stabilizing and forming a closed rotating liquid ring, establishing negative pressure suction capability. At the same time, the dedicated liquid storage tank 8 can retain a fixed volume of working medium after shutdown, preventing all the medium from flowing back and being drained. It achieves active self-priming by relying on the eccentric ring negative pressure principle, and the working fluid is always retained in the pump before each start-up, eliminating the need for repeated manual pre-priming. This solves the problems of liquid loss during shutdown and restart failure of conventional self-priming pumps, greatly improving the self-priming stability and continuous operation capability under intermittent start-stop conditions.

[0025] The axial separator 9 enables functional partitioning of the liquid ring vacuum wheel 4, separating the water intake and liquid replenishment processes from the liquid ring forming process. Only the lower water intake section extends into the liquid storage tank 8 to draw a small amount of working medium as needed, eliminating the need for continuous agitation of a large amount of stored liquid. The liquid in the liquid storage tank 8 reaches approximately 2 / 3 of the overall height of the liquid ring vacuum wheel 4. The upper liquid ring forming section is free from the large-scale disturbance of the stored liquid, maintaining a sealed liquid ring by retaining a small amount of medium through the suspension structure 4-1. This significantly reduces the agitation range and frictional contact area of ​​the medium, reducing ineffective liquid resistance loss at the source. It effectively avoids the high resistance and high energy consumption defects caused by the continuous agitation of the integrated liquid ring vacuum wheel 4, significantly reducing the ineffective work done during the rotation of the vacuum wheel, greatly reducing the overall power consumption of the machine, and improving the energy efficiency of the equipment. At the same time, the segmented independent working mode can achieve precise water intake and stable ring formation. The two working conditions do not interfere with each other, the liquid ring formation is uniform and continuous, and the negative pressure output is stable, ensuring that the equipment always has excellent self-priming performance under the premise of low power consumption operation.

[0026] The suspension structure 4-1 is configured as an arc-shaped protrusion evenly arranged along the circumference of the wheel body; the arc-shaped protrusion has a convex surface and a concave surface, and the convex surface and the concave surface are arranged opposite to each other; the concave surface of the arc-shaped protrusion faces the rotation direction of the main shaft; the water intake structure 4-2 is configured as a continuous spiral blade, and the blade segments of the spiral blade are arranged axially in sequence along the axis. When the liquid ring vacuum wheel 4 rotates at high speed, the medium is thrown out towards the wall of the eccentric chamber 6 under the action of centrifugal force and forms a liquid ring. Utilizing the liquid-collecting effect of the arc-shaped concave surface rotating in the same direction, the arc-shaped concave surface actively faces the medium during the rotation of the wheel, forming a wrapping, retention and buffering effect on the liquid flowing against the wall in the chamber, which greatly suppresses the tangential escape and splashing of the liquid. At the same time, the evenly arranged arc-shaped protrusions can uniformly comb the circumferential liquid, so that the medium continuously and evenly accumulates against the wall in the gap of the eccentric chamber. It can maintain a continuous, uniform and sealed complete liquid ring in the eccentric chamber 6 for a long time, avoiding problems such as liquid ring tearing, gaps and fluctuations under high-speed rotation conditions. This ensures that the negative pressure of the liquid ring vacuum wheel is established quickly and the pumping pressure is stable, which greatly improves the pump body's self-priming success rate and self-priming continuity.

[0027] The lower water intake section of the liquid ring vacuum wheel 4 uses continuous spiral blades as the water intake structure 4-2. The entire continuous spiral blade has axial conveying capability. When rotating, it can continuously lift the medium at the bottom of the liquid storage tank 8, providing stable working liquid replenishment for the upper liquid ring forming section. At the same time, the axial segmented structure of the blade breaks the disadvantage of the continuous blade stirring the fluid throughout the entire area. The blade only forms a directional liquid lifting channel in the segmented area, and the non-blade area is an empty pressure relief area. During the rotation, only the effective liquid replenishment flow of vertical lifting is generated, and there will be no lateral turbulence, whole-area stirring and forced disturbance to the medium in the large area of ​​the liquid storage tank 8.

[0028] The axial separator 9 is an annular baffle, and the outer diameter of the annular baffle is equal to that of the liquid ring forming section. The large-flow turbulence and a large amount of upward-rushing liquid generated by the agitation of the spiral blades in the water intake section are blocked by the solid surface of the annular baffle and cannot directly flow into the upper liquid ring forming area. Only a very thin layer of medium and a trace amount of gas can flow through the outer edge gap, without impacting or breaking up the upper forming liquid ring, thus achieving a large-flow liquid isolation. The upper and lower sections can have a trace amount of medium and gas exchanged, balancing the pressure in the upper and lower areas, eliminating the additional rotational resistance caused by the pressure difference, and further reducing the power consumption of the equipment while stabilizing the self-priming performance.

[0029] like Figure 5 As shown, the centrifugal pump is provided with a first air inlet duct 5-1, and the low-pressure suction zone in the eccentric chamber 6 is provided with a second air inlet duct 6-1 and an overflow channel 6-2. The first air inlet duct 5-1 and the second air inlet duct 6-1 are connected in an air passage. An air inlet hole 6-3 is opened at the hub of the suspension structure 4-1, and the air inlet hole 6-3 is connected in an air passage to the second air inlet duct. The opening of the overflow channel 6-2 is flush with the bottom end face of the axial separator 9. The overflow channel 6-2 and the air inlet hole 6-3 are respectively connected to a guide pipe provided on the outside of the housing 1, and the guide pipe extends to the equipment pit. The centrifugal pump is equipped with a first air inlet duct 5-1 and a second air inlet duct 6-1 arranged in the low-pressure suction area of ​​the eccentric cavity. The two air passages are connected. At the same time, the suspension structure 4-1 has an air inlet hole 6-3 that communicates with the second air inlet duct 6-1. The three form a multi-point connected air extraction passage. During operation, it can simultaneously extract air accumulated in the centrifugal cavity, suction pipe and dead corner of the wheel body. Multi-point exhaust has no gas retention, and it can quickly establish a self-priming negative pressure, effectively avoiding the mechanical seal dry running problem caused by air accumulation in the pump cavity. The opening of the overflow channel 6-2 is flush with the bottom end face of the axial partition 9. After the accumulated liquid collects on the bottom surface of the axial partition 9, it can all be discharged through the overflow channel 6-2. -2 output, precisely control the working fluid level inside the eccentric cavity, which not only avoids excessive liquid accumulation being continuously stirred by the spiral blades, resulting in additional liquid resistance and increased operating power consumption, but also prevents insufficient liquid level from causing liquid ring breakage and negative pressure failure; the air inlet 6-3 and the overflow channel 6-2 are respectively connected to independent closed guide pipes and led to the equipment pit. The oil-gas mixture extracted from the pump and excess hazardous waste liquid are transported and collected centrally through closed pipelines, so that the medium will not directly volatilize and diffuse into the outside space, avoiding the safety risk of Class A and B flammable and explosive media volatilizing to form an explosive mixture. At the same time, the waste liquid is uniformly recycled, reducing medium loss and on-site corrosion pollution.

[0030] It also includes a bearing housing, which is divided into an upper oil reservoir 10 and a lower oil reservoir 11. The upper oil reservoir 10 and the lower oil reservoir 11 are located at the upper and lower ends of the radial bearing, respectively, and the upper and lower oil reservoirs 11 are in liquid communication. An oil supply pipeline 12 connecting the upper oil reservoir 10 and the lower oil reservoir 11 is provided on the outside of the housing 1. An oil supply port 13 and a valve body 14 are provided on the oil supply pipeline 12. The valve body 14 is used to control the opening and closing of the oil supply pipeline 12. An oil supply ring 11-1 is provided at the bottom of the lower oil reservoir 11. The oil supply ring 11-1 is sleeved on the outer circumference of the vertical spindle 3. A spiral guide groove is provided on the oil supply ring 11-1. When the vertical spindle 3 rotates, the spiral guide groove transports the lubricating medium in the lower oil reservoir 11 to the oil supply pipeline 12. The upper oil storage chamber 10 and the lower oil storage chamber 11 are internally interconnected, and lubrication can be achieved by gravity. An oil supply pipeline 12 connecting the upper and lower oil storage chambers 11 is added to the outside of the housing 1. The pipeline is equipped with an oil replenishment port 13 and a valve body 14. The valve body 14 is used to control the opening and closing of the oil supply pipeline 12. When the valve body 14 is opened, lubricating medium can be replenished into the oil circuit through the oil replenishment port 13. When no oil replenishment is needed, the valve body 14 is closed. The system remains closed, blocking the passage of the oil supply pipeline 12. The oil supply ring 11-1 directs the lubricating oil from the lower oil storage chamber 11 upwards to the upper oil storage chamber 10, forming a closed-loop forced circulation oil circuit. The upper and lower oil storage chambers 11 supply oil synchronously from both ends of the bearing, completely immersing the bearing friction pair and preventing localized dry friction from generating high-temperature sparks. This meets the explosion-proof requirements for transporting Class A and B flammable and explosive media. The external oil replenishment port 13 supports adding lubricating media without stopping the machine, simplifying daily maintenance. The oil supply ring 11-1 forces the lubricating oil to circulate, continuously carrying away the bearing's frictional heat. The dual-chamber structure increases the total oil storage capacity, enhances heat dissipation and buffering capabilities, stabilizes the bearing's operating temperature, and extends the service life of the bearing and lubricating oil. Simultaneously, the chambers have built-in connecting channels, allowing for basic lubrication by the oil's own weight during valve maintenance, reducing the risk of bearing wear and increasing the reliability of continuous equipment operation.

[0031] The bearing assembly inside the bearing housing includes a thrust bearing assembly and a radial bearing. The vertical spindle 3 is rotatably mounted inside the thrust bearing assembly and the radial bearing. The radial bearing can be selected as a ball bearing or a sliding bearing according to the actual operating load of the pump body, adapting to different working conditions and load requirements. The internal space of the bearing housing is divided into an upper oil chamber and a lower oil chamber. The upper oil chamber is located above the radial bearing, and the lower oil chamber is located below the radial bearing. The upper and lower oil chambers are interconnected through a connecting oil passage. The bearing housing is pre-filled with lubricating oil, which provides immersion lubrication to the thrust bearing assembly and the radial bearing.

[0032] This radial bearing structure allows for flexible selection of two types to adapt to different operating loads. The upper and lower oil chambers are interconnected through a connecting oil circuit, ensuring uniform lubrication. This allows for the formation of a complete oil-immersed lubricating film on the thrust bearing assembly and radial bearing throughout the entire process, significantly reducing spindle rotation friction loss. At the same time, the continuous flow of lubricating oil carries away the operating heat of the bearing, preventing high-temperature wear and sintering, and effectively improving the operational stability and service life of the bearing assembly.

[0033] A heat-insulating cavity 15 is provided between the eccentric chamber 6 and the lower oil chamber. Utilizing the continuous evacuation action of the eccentric chamber, the air inside the heat-insulating cavity 15 is continuously extracted, creating a near-vacuum low-pressure environment with only rarefied air remaining. This rarefied air has low density and extremely low thermal conductivity, significantly reducing heat conduction and convection heat transfer capabilities. Similar to the vacuum insulation structure of a thermos, it effectively blocks the upward transfer of heat from the high-temperature medium below, forming a reliable heat-insulating layer between the high-temperature medium side and the lubricating oil side. This prevents the lubricating oil in the lower oil chamber from overheating and deteriorating due to heat radiation and conduction from the high-temperature medium, thus maintaining the stable lubricating performance of the lubricating oil.

[0034] The insulation cavity 15 can be adapted to the working conditions of the medium and the set temperature: it can be filled with insulation and heat preservation materials, or it can be set as a cooling cavity or a heat preservation cavity. If the medium is prone to solidification and crystallization at room temperature, the insulation cavity 15 can be configured as a heat preservation cavity, using steam heat preservation or electric heat tracing for heat preservation; thus, the function of the insulation cavity 15 is not limited to cooling and temperature reduction, but can also take into account heat preservation and other derivative temperature control functions.

[0035] To intuitively quantify the heat insulation capacity of the heat insulation cavity 15 and clarify the influence of cavity height changes on the heat blocking effect, the applicant conducted a steady-state temperature test of the entire machine: a heat insulation cavity 15 with a total axial height of 85mm was selected as the test sample, and temperature measuring points were set up every 5mm along the cavity height direction. The temperature of the main shaft on the medium side and the temperature of the side wall of the heat insulation cavity 15 near the lower oil cavity were collected at each measuring point. The discrete data table of temperature gradient of the heat insulation cavity 15 was compiled. The continuous gradient data intuitively reflects the temperature decay heat insulation effect of the vacuum cavity. The test data are as follows (see Table 1 for details).

[0036] Table 1. Temperature sampling data of insulation cavity 15 at different axial heights

[0037] Through Table 1 and Figure 6As shown, the temperature measurement data shows that when the cavity height is 0mm, the temperature of both the main shaft and the heat-insulating sidewall is 200℃. As the height of the heat-insulating cavity 15 increases, the temperatures at both measurement points decrease linearly and synchronously. When the cavity height reaches 85mm, the main shaft temperature drops to 120℃, and the temperature of the sidewall of the heat-insulating cavity 15 near the lubricating oil cavity is only 50℃, with a temperature difference of 70℃ between the two points. The data proves that the near-vacuum rarefied air inside the heat-insulating cavity 15 has extremely weak thermal conductivity, which can form a continuous temperature attenuation gradient along the axial direction, effectively blocking the heat generated by the high-temperature medium below from being transferred upward to the lubricating oil cavity, significantly reducing the working temperature of the lubricating oil, and preventing the lubricating oil from deteriorating at high temperatures. Moreover, the heat insulation and cooling effect is stably linearly related to the cavity height, and the cavity height can be adjusted according to the medium temperature conditions to adapt to the transportation needs of various high-temperature corrosive media.

[0038] A first thrust ring 16 is assembled between the lower oil chamber and the heat insulation chamber, and a second thrust ring 17 is assembled between the heat insulation chamber and the eccentric chamber 6. The first thrust ring 16 and the second thrust ring 17 are coaxially sleeved on the outer periphery of the vertical spindle 3. Spiral guide grooves are formed on the surface of the first thrust ring 16 and the second thrust ring 17. When the vertical spindle 3 rotates, the spiral guide grooves apply a downward axial thrust to the upward-moving medium, inhibiting the upward leakage of the medium. The medium inside the eccentric cavity is prone to upward leakage along the main shaft gap under the action of pressure difference. When the main shaft rotates, it drives the thrust ring to operate synchronously. The spiral guide groove generates a downward axial pumping thrust on the medium rising in the gap, which counteracts the upward force of the medium and achieves dynamic leakage prevention. The two-stage thrust ring forms two layered interception barriers, which doubly inhibit the upward leakage of the medium and prevent hazardous media from entering the bearing oil cavity and contaminating the lubricating oil, thus ensuring stable bearing lubrication. The spiral guide groove is designed so that there is no contact friction loss during operation, which is suitable for long-term transportation of media containing impurities and crystals. At the same time, it prevents flammable and explosive media from entering the high-temperature area of ​​the bearing, eliminates the risk of flash explosion and fire, and improves the safety and service life of the equipment.

[0039] It also includes a sealing and isolation assembly, which is a mechanical seal 18 fixed to the bottom of the lower oil reservoir 11. The mechanical seal 18 adopts a single-end-face sealing structure or a double-end-face sealing structure. When the mechanical seal 18 adopts a single-end-face sealing structure, the end face of the mechanical seal 18 is immersed in the lubricating oil in the lower oil reservoir 11, relying on the lubricating oil for continuous lubrication and cooling. When the mechanical seal 18 adopts a double-end-face sealing structure, lubrication and cooling are achieved by pre-filling isolation fluid. The sealing friction pair of the mechanical seal 18 is permanently immersed in the lubricating oil in the lower oil reservoir 11. A dry-running seal structure is formed, relying on the lubricating oil to continuously generate a complete oil film on the sealing end face, realizing the physical isolation between the bearing-side lubricating oil and the medium conveyed in the eccentric vacuum chamber. It is not affected by the liquid level of the medium below or the vacuum negative pressure state. There is no risk of dry running during the entire vacuuming process, effectively avoiding sealing ring burning, leakage and damage, and extending the service life of the seal. At the same time, the lubricating oil layer isolates corrosive media from direct contact with the sealing friction pair, reducing the chemical corrosion and erosion damage of the medium. The stability of the seal operation is significantly improved, and it can be adapted to various corrosive media conveying conditions, solving the pain points of easy damage and frequent replacement of traditional self-priming pump mechanical seals.

[0040] The pump body assembly is equipped with a liquid inlet suction pipe 19 located at the bottom end of the centrifugal pump impeller 5. The liquid inlet suction pipe 19 can adopt any one of three structures: bottom inlet, side inlet, or top inlet. This pump has three differentiated liquid inlet layout structures, corresponding to high, medium, and low tank liquid levels and different on-site pipeline installation space conditions. The three liquid inlet pipelines are only distinguished by the front-end connection structure. The impeller, eccentric chamber 6, heat insulation chamber 15, lubricating oil chamber, and pump casing core structure inside the pump body are completely interchangeable. The layout can be switched without disassembling or modifying the main pump body components. The low-level liquid inlet layout is suitable for low-level tanks and low installation platforms. The medium-level liquid inlet layout is suitable for conventional standard tanks and open pipeline installation sites. The high-level liquid inlet layout is suitable for high-level tanks and installation scenarios with dense bottom pipelines and limited lateral space. It can match various working conditions such as different tank liquid levels, plant pipeline routes, and equipment installation space limitations. The entire set of equipment can be adapted to different working conditions by simply replacing the front-end connecting pipeline. The mounting base, fixing flange, and main body dimensions of the whole machine do not need to be adjusted. There is no need to produce multiple specifications of pump bodies for different working conditions, which effectively reduces the number of equipment models and categories and lowers the production and storage costs of spare parts. When adjusting the working conditions on site or modifying the pipeline, there is no need to disassemble the core components inside the pump. The modification and commissioning cycle is short, and the overall versatility and adaptability of the equipment are significantly improved.

[0041] The liquid ring vacuum wheel 4 is made of any one of aluminum alloy, copper alloy, or high-strength non-metallic antistatic material. Aluminum alloy and copper alloy are soft and do not easily generate sparks when rubbing or impacting with media impurities. Antistatic non-metallic materials can eliminate the accumulation of static electricity during operation, thus avoiding the risk of fire and explosion of flammable and explosive media. All three types of materials have good corrosion resistance and wear resistance, making them suitable for long-term transportation of hazardous chemical media containing crystals and impurities. At the same time, the materials have low density, reducing the weight of the vacuum wheel, lowering the bearing load and the overall power consumption of the machine. Furthermore, the material can be flexibly selected according to the on-site media conditions, making the equipment highly versatile.

[0042] This invention discloses multiple technical solutions, but does not provide any contrary technical teachings. The contents not covered in this invention are applicable to existing technologies. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention; at the same time, for those skilled in the art, based on the ideas of this invention, there will be changes in specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum impeller, comprising: The system comprises a housing, a drive motor, a vertical spindle, and a pump assembly, wherein the drive motor is connected to the vertical spindle for transmission. The pump assembly includes a liquid ring vacuum wheel and a centrifugal pump impeller coaxially mounted and arranged from top to bottom along the vertical spindle. The housing contains an eccentric chamber for accommodating the liquid ring vacuum wheel and a centrifugal chamber for accommodating the centrifugal pump impeller, with the eccentric chamber and the centrifugal chamber connected by an air passage. The central axis of the eccentric chamber is eccentrically positioned relative to the axis of the vertical spindle, and a liquid storage tank for storing a medium is formed within the eccentric chamber. The liquid ring vacuum wheel is divided into an upper liquid ring forming section and a lower water intake section by an axial separator. The liquid ring forming section has a suspension structure, and the water intake section has a water intake structure, which is placed within the liquid storage tank.

2. The vertical coaxial double impeller self-priming pump with integrated liquid ring vacuum wheel according to claim 1, characterized in that, The suspension structure is configured as arc-shaped protrusions evenly arranged along the circumference of the wheel body; the concave surface of the arc-shaped protrusions faces the rotation direction of the main shaft; the water intake structure is configured as continuous spiral blades, and the blade segments of the spiral blades are arranged axially in sequence along the axis.

3. A vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel according to claim 1, characterized in that, The axial separator is an annular partition, and the outer diameter of the annular partition is equal to that of the liquid ring forming section.

4. A vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel according to claim 1, characterized in that, The centrifugal pump is provided with a first air inlet channel, and the low-pressure suction zone of the eccentric chamber is provided with a second air inlet channel and an overflow channel. The first air inlet channel and the second air inlet channel are connected in an air passage. An air inlet hole is opened at the hub of the suspension structure, and the air inlet hole is connected in an air passage to the second air inlet channel. The opening of the overflow channel is flush with the bottom end face of the axial separator. The overflow channel and the air inlet hole are respectively connected to a guide pipe provided on the outside of the housing, and the guide pipe extends to the equipment pit.

5. A vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel according to claim 1, characterized in that, It also includes a bearing housing, which is divided into an upper oil reservoir and a lower oil reservoir. The upper and lower oil reservoirs are located at the upper and lower ends of the radial bearing, respectively, and are in liquid communication with each other. An oil supply pipeline connecting the upper and lower oil reservoirs is provided on the outside of the housing. The oil supply pipeline is provided with an oil replenishment port and a valve body. The valve body is used to control the opening and closing of the oil supply pipeline. An oil supply ring is provided at the bottom of the lower oil reservoir. The oil supply ring is sleeved on the outer circumference of the vertical spindle. A spiral guide groove is provided on the oil supply ring. When the vertical spindle rotates, the spiral guide groove transports the lubricating medium in the lower oil reservoir to the oil supply pipeline.

6. A vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel according to claim 5, characterized in that, A heat-insulating cavity is provided between the eccentric chamber and the lower oil chamber.

7. A vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel according to claim 6, characterized in that, A first thrust ring is assembled between the lower oil chamber and the heat insulation chamber, and a second thrust ring is assembled between the heat insulation chamber and the eccentric chamber. The first and second thrust rings are coaxially sleeved on the outer circumference of the vertical spindle. Spiral guide grooves are formed on the surface of both the first and second thrust rings. When the vertical spindle rotates, the spiral guide grooves apply a downward axial thrust to the upward-moving medium, inhibiting the upward leakage of the medium.

8. A vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel according to claim 5, characterized in that, It also includes a sealing and isolation component, which is a mechanical seal fixed to the bottom of the lower oil storage chamber.

9. A vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel according to claim 1, characterized in that, The pump body assembly is provided with a liquid inlet suction pipe located at the bottom end of the centrifugal pump impeller. The liquid inlet suction pipe can be any one of three structures: bottom inlet, side inlet, or top inlet.

10. A vertical coaxial double impeller self-priming pump with an integrated liquid ring vacuum wheel according to claim 1, characterized in that, The liquid ring vacuum wheel is made of any one of aluminum alloy, copper alloy, or high-strength non-metallic antistatic material.

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