High-efficiency self-priming pump with external mixing

Abstract

The application discloses a kind of outer mixing type high-efficiency self-priming pump, belongs to self-priming pump technical field, including centrifugal pump and with centrifugal pump communication outer mixing type backflow device, the outer mixing type backflow device includes inlet pipe and gas-liquid mixing tank, the inlet pipe outlet flange is connected with centrifugal pump entrance, inlet flange is connected with self-priming pump inlet pipeline, the bottom of gas-liquid mixing tank exports is provided with the backflow valve that can self-adaptively change switch state, the bottom end of backflow valve is provided with diffusion discharge pipe assembly.Pump is stored in tank before being started certain liquid level medium, centrifugal pump outlet discharge medium is first backflowed to gas-liquid mixing tank, after gas-liquid separation, it is discharged from gas-liquid mixing tank outlet instead of being directly discharged, ensure that even if flow interruption phenomenon occurs, air is mixed into inlet pipeline even without medium suction, centrifugal pump is still full of medium, can normally operate.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of self-priming pumps, and particularly relates to an external mixing type high-efficiency self-priming pump. BACKGROUND

[0002] With the progress of industry, the process of the petroleum and petrochemical industry is constantly updated, and the working condition is more and more complex and changeable, which brings great challenges to the self-priming pump industry. The self-priming pump is often used in the end of the chemical process and is used for discharging process waste and wastewater. Generally, the medium is discharged for a long time and quantitatively. The self-priming pump is always running without stopping, or the medium is uniformly discharged into a liquid storage tank. The self-priming pump is intermittently operated. When the liquid storage tank is filled with medium, the pump is started to discharge the medium. When the medium in the liquid storage tank is exhausted, the pump is stopped to store water again for the next operation.

[0003] In recent years, a kind of working condition appears. The working condition cannot discharge a certain amount of medium at a certain time, and requires the self-priming pump to be continuously operated without stopping when the entire process is running. The medium is discharged and cannot be accumulated. The working condition often requires a high suction height. The existing ordinary self-priming pump is not suitable for this kind of working condition which is long-term running, but the discharge is not at a certain time and the amount is very small, and the suction height is high. Once this situation occurs, the medium cannot be sucked or the flow is interrupted, and the mechanical seal in the pump is dry and damaged.

[0004] Therefore, there is an urgent need for a self-priming pump with a high suction height, which can continuously operate without stopping the pump during the self-priming and discharging process, and can continuously discharge the medium at any time. The self-priming pump can ensure the continuity of work and meet the requirements of the process flow on the site. SUMMARY

[0005] The purpose of the application is to provide a self-priming pump suitable for the above-mentioned working condition, so as to solve the problem that the existing self-priming pump cannot normally operate in the working condition of high suction height and medium discharging at a certain time.

[0006] To achieve the above-mentioned purpose, the application provides the following technical scheme: an external mixing type high-efficiency self-priming pump, comprising a centrifugal pump and an external mixing type reflux device communicated with the centrifugal pump. The external mixing type reflux device comprises an inlet pipe and a gas-liquid mixing tank. The outlet flange of the inlet pipe is connected with the inlet of the centrifugal pump, and the inlet flange is connected with the inlet pipeline of the self-priming pump. One side of the gas-liquid mixing tank is communicated with the outlet of the centrifugal pump through a reflux pipe. A reflux valve capable of self-adaptively changing the switching state is arranged at the bottom outlet of the gas-liquid mixing tank. A diffusion discharge pipe assembly is arranged at the bottom end of the reflux valve. The diffusion discharge pipe assembly is communicated with the inlet pipe. The gas-liquid mixing tank, the reflux valve and the diffusion discharge pipe assembly are connected into an integrated body through bolts B.

[0007] Further, the backflow valve comprises a sealing adjusting block mounted at the bottom end of the gas-liquid mixing tank, a bolt A arranged in the middle of the sealing adjusting block, and a nut, a sealing plate, a spring and a jet plate successively sleeved on the outer wall of the bolt A from top to bottom; the jet plate is installed in the lower part of the inner cavity of the sealing adjusting block through external threads; the threaded end of the bolt A extends out of the center of the inner wall of the jet plate, penetrates into the spring and leads out of the center of the inner wall of the sealing plate through the threaded connection with the nut, and can move up and down in the central hole of the jet plate under the spring elastic force and the medium pressure.

[0008] Further, the top surface of the jet plate is a conical surface, and a plurality of through holes perpendicular to the conical surface are uniformly distributed on the conical surface, and the center lines of the plurality of through holes converge at a point.

[0009] Further, the gas-liquid mixing tank comprises a tank body, a partition plate arranged in the inner cavity of the tank body, and a baffle arranged below the partition plate; a water injection pipe is arranged at the bottom of one side of the outer wall of the tank body, and a water injection cover is mounted at the top of the water injection pipe; a backflow pipe is arranged at the bottom of the other side of the tank body and is in communication with the output port of the centrifugal pump.

[0010] Further, a circular hole is arranged in the middle of the partition plate, and the partition plate divides the tank body into two parts; the tank body is communicated with the two parts through the hole in the middle of the partition plate; the baffle is in a spiral shape and is in the form of an open arc; the medium discharged from the outlet of the centrifugal pump enters the gas-liquid mixing tank through the backflow pipe and flows along the spiral flow channel formed by the tank body, the partition plate and the baffle; the gas in the medium is separated from the liquid during the flowing process and is collected in the upper part of the tank body from the hollow part of the partition plate and discharged.

[0011] Further, the partition plate is lower than the bottom of the topmost pipeline of the inlet pipe to ensure that there is enough medium in the centrifugal pump; even if the medium in the inlet pipeline is cut off, the centrifugal pump can still operate normally.

[0012] Further, the diffusion discharge assembly comprises a diffusion discharge pipe and a suction pipe; the diffusion discharge pipe is in the form of a pear-shaped structure with a wide upper part and a narrow lower part, and the bottom part is in communication with the outlet end of the inlet pipe; one end of the suction pipe is in communication with the upper part of the diffusion discharge pipe, and the other end is in communication with the top of the inlet pipe.

[0013] The beneficial effects of the present application are as follows:

[0014] 1. Before starting the pump, a certain liquid level of medium is stored in the tank body; the medium discharged from the outlet of the centrifugal pump is first backflowed to the gas-liquid mixing tank, and then discharged from the outlet of the gas-liquid mixing tank after gas-liquid separation, instead of being directly discharged, so that even if the cut-off phenomenon occurs, the centrifugal pump is still full of medium when air is mixed into the inlet pipeline or even there is no medium to be sucked, and the centrifugal pump can operate normally.

[0015] 2. The baffle and the partition form a spiral flow channel in the tank, the medium discharged from the centrifugal pump outlet enters the gas-liquid mixing tank along the reflux pipe, and flows along the spiral baffle, which prolongs the flow time of the medium in the tank, makes the gas-liquid separation more sufficient, the impact force of the flow liquid passing through the baffle is buffered, the medium flows smoothly, and the performance of the pump is more stable and reliable;

[0016] 3. Compared with a single nozzle, the multiple nozzles form a higher vacuum degree, the vacuum formed by the two nozzles and the centrifugal pump impeller inlet sucks the medium, the suction capacity in the inlet pipeline is stronger, and the problem of low suction height of the original external mixing type and internal mixing type self-priming pump is solved;

[0017] 4. After the vacuum pumping and air suction process is completed, the reflux device is automatically closed, the reflux loss in the normal working state is reduced, and the high-efficiency and energy-saving operation of the self-priming pump is ensured.

[0018] 5. The diffusion discharge pipe is in a pear-shaped structure of thickening upwards and thinning downwards, the medium entering the diffusion discharge pipe can be further pressurized and accelerated through the contraction of the pipe diameter, so that the suction of the gas at the top of the inlet pipe by the suction pipe is enhanced, the medium suction capacity is improved, and the deficiency of low suction height of the ordinary self-priming pump is made up.

[0019] 6. The reflux valve is in a split structure, the injection plate and the sealing adjusting block are connected by threads, the height of the gathering point of each through hole on the injection plate in the diffusion discharge pipe is adjusted, so that a higher vacuum degree is formed in the diffusion discharge pipe, a nut is arranged on the top of the bolt, the nut is adjustable, the distance between the top opening of the sealing plate and the sealing adjusting block (i.e. the flow area) is ensured not to become too small due to the up-down adjustment of the injection plate, so that the insufficient medium reflux amount is avoided, and the equipment operation is affected.

[0020] 7. The reflux valve can be replaced as a whole, and the equipment maintenance time is saved.

[0021] 8. A group of nozzles are arranged on the injection plate which supports and adjusts the spring, the free falling of the original medium is changed into the injection of the nozzles, the medium reflux speed is accelerated, the suction force of the self-priming pump is stronger, and the suction height is higher. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a structure diagram of the external mixing type high-efficiency self-priming pump of the application;

[0023] Figure 2 It is a partial diagram of the external mixing type high-efficiency self-priming pump of the application;

[0024] Figure 3 It is an A-A cross-sectional view of the application;

[0025] Figure 4 It is a schematic view of the injection plate of the application;

[0026] In the diagram: 1. External mixing reflux device; 11. Inlet pipe; 12. Gas-liquid mixing tank; 121. Water injection pipe; 1211. Water injection cover; 122. Tank flange; 123. Tank body; 124. Baffle; 125. Baffle; 126. Reflux pipe; 13. Reflux valve; 131. Bolt A; 132. Nut; 133. Sealing plate; 134. Sealing adjustment block; 135. Spring; 136. Spray plate; 14. Diffusion discharge pipe assembly; 141. Suction pipe; 142. Diffusion discharge pipe; 15. Bolt B; 2. Centrifugal pump; 3. Inlet pipeline. Detailed Implementation

[0027] 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.

[0028] like Figures 1-4 As shown, this invention discloses an external mixing high-efficiency self-priming pump, comprising a centrifugal pump 2 and an external mixing reflux device 1 connected to the centrifugal pump 2. The external mixing reflux device 1 includes an inlet pipe 11 and a gas-liquid mixing tank 12. The outlet flange of the inlet pipe 11 is connected to the inlet of the centrifugal pump 2, and the inlet flange is connected to the inlet pipeline 3 of the self-priming pump. One side of the gas-liquid mixing tank 12 is connected to the outlet of the centrifugal pump 2 through a reflux pipe 126. A reflux valve 13 with adaptively changeable switching state is provided at the bottom outlet of the gas-liquid mixing tank 12. A diffusion discharge pipe assembly 14 is provided at the bottom end of the reflux valve 13, and the diffusion discharge pipe assembly 14 is connected to the inlet pipe 11. The gas-liquid mixing tank 12, the reflux valve 13, and the diffusion discharge pipe assembly 14 are connected by a screw... Bolt B15 is integrated into one unit; the reflux valve 13 includes a sealing adjustment block 134 installed at the bottom of the gas-liquid mixing tank 12, a bolt A131 set in the middle of the sealing adjustment block 134, and a nut 132, a sealing plate 133, a spring 135 and a spray plate 136 sequentially fitted on the outer wall of the bolt A131 from top to bottom. The spray plate 136 is installed in the lower part of the inner cavity of the sealing adjustment block 134 through external threads. The threaded end of the bolt A131 extends out of the center position of the inner wall of the spray plate 136, enters the spring 135, and then exits through the center position of the inner wall of the sealing plate 133 to be threadedly connected to the nut 132. It can move up and down along the middle hole of the spray plate 136 under the action of the elastic force of the spring 135 and the medium pressure.

[0029] The top surface of the spray plate 136 is a conical surface, with several through holes evenly distributed on the conical surface, and the center lines of the several through holes converge at a point.

[0030] The gas-liquid mixing tank 12 comprises a tank body 123, a partition plate 124 arranged in the inner cavity of the tank body 123, and a baffle plate 125 arranged below the partition plate 124. The outer wall of the tank body 123 is provided with a water injection pipe 121 at the bottom of one side, and the top of the water injection pipe 121 is provided with a water injection cover 1211. The tank body 123 is provided with a return pipe 126 at the bottom of the other side, which is communicated with the output port of the centrifugal pump 2.

[0031] A circular hole is arranged in the middle of the partition plate 124, and the tank body 123 is divided into upper and lower two parts by the partition plate 124. The upper and lower two parts of the tank body 123 are communicated through the hole in the middle of the partition plate 124. The baffle plate 125 is in a spiral shape and in the form of an open arc. The medium discharged from the outlet of the centrifugal pump 2 enters the gas-liquid mixing tank 12 along the return pipe 126, and flows along the spiral flow channel formed by the tank body 123, the partition plate 124 and the baffle plate 125. The gas in the medium is separated from the liquid during the flowing process and is collected in the upper part of the tank body 123 from the hole in the partition plate 124 and discharged.

[0032] The diffusion discharge assembly 14 comprises a diffusion discharge pipe 142 and a suction pipe 141. The diffusion discharge pipe 142 is in the form of a pear-shaped structure with a wide upper part and a narrow lower part, and the bottom of the diffusion discharge pipe 142 is communicated with the outlet end of the inlet pipe 11. One end of the suction pipe 141 is communicated with the upper part of the diffusion discharge pipe 142, and the other end is communicated with the top of the inlet pipe 11.

[0033] The partition plate 124 is lower than the bottom of the topmost pipeline of the inlet pipe 11 to ensure that there is enough medium in the centrifugal pump 2. Even if the medium in the inlet pipeline 3 is cut off, the centrifugal pump 2 can still operate normally.

[0034] Working process: before the new pump is put into use, open the water injection cover 121 to inject water into the gas-liquid mixing tank 12, when water comes out of the water injection pipe 121, it indicates that the liquid level in the gas-liquid mixing tank 12 has reached the predetermined position, cover the water injection cover 121, start the self-priming pump, at this time the centrifugal pump 2 is full of medium, the self-priming pump inlet pipeline 3, the gas-liquid mixing tank 12 and the top of the inlet pipe 11 are all full of air, the nut of the bolt A 131 is attached to the bottom of the jet plate 136, and the sealing plate 133 is kept a certain distance from the top of the sealing adjusting block 134 under the elastic force of the spring 135 to ensure the water flow; the centrifugal pump 2 operates, the medium stored in the pump and the inlet pipe 11 is discharged from the pump outlet, and enters the channel isolated by the baffle 125 and the partition plate 124 in the tank body 123, the medium flows to the middle of the tank body 123 under the guidance of the spiral baffle 125, and then enters the diffusion discharge pipe 142 through the backflow valve 13 to flow back to the outlet end of the inlet pipe 11 and re-enter the centrifugal pump 2, because the medium originally stored in the centrifugal pump 2 and the inlet pipe 11 is injected into the gas-liquid mixing tank 12, a vacuum is formed in the inlet pipe 11 and the pump, the gas in the centrifugal pump 2 inlet pipeline 3 is sucked into the centrifugal pump 2 under the action of the vacuum and mixed with the residual medium in the pump, and then enters the gas-liquid mixing tank 12, the gas-liquid mixture entering the gas-liquid mixing tank 12 rotates along the partition plate 124 after entering the channel isolated by the baffle 125 and the partition plate 124, the gas in the gas-liquid mixture floats up and the liquid sinks down, when they flow to the outlet, the gas flows from the hole in the middle of the partition plate 124 to the top of the tank body 123 and flows from the tank flange 122 to the pump outlet pipeline, the liquid flows down from the opening between the sealing plate 124 and the sealing adjusting block 134, and flows back to the inlet pipe 11 and the centrifugal pump 2 through the diffusion discharge pipe assembly 14; in this way, the cycle is repeated until the gas in the pump body and the inlet pipeline 3 is discharged, the gas-liquid mixing tank 12 is filled with high-pressure medium, at this time the sealing plate 133 falls under the pressure difference between the vacuum degree of the centrifugal pump 2 inlet and the high-pressure medium in the gas-liquid mixing tank 12 to cover the hole in the sealing adjusting block 134, the backflow valve 13 is closed, and the pump works normally; when the medium in the storage tank is exhausted and the self-priming pump cannot suck the medium, the liquid level in the gas-liquid mixing tank 12 decreases due to no subsequent medium supplement, the pressure of the medium in the tank decreases, the backflow valve 13 opens, and because the inlet of the inlet pipe 11 is higher than the partition plate 124, a part of the medium in the gas-liquid mixing tank 12 will remain, the centrifugal pump 2 keeps normal operation by the medium stored in the gas-liquid mixing tank 12, until the storage tank is full of medium again.

[0035] The top side wall of the diffusion discharge pipe 142 is provided with a suction pipe 141 which communicates with the top of the inlet pipe 11. The top of the diffusion discharge pipe 142 is provided with a spray plate 136 having a conical surface and a plurality of through holes which are perpendicular to the conical surface and are uniformly distributed on the conical surface. The center lines of all the through holes converge at a point. When the medium flows through the through holes on the spray plate 136, the medium is sprayed from the through holes and converges at the point, forming a very strong impact force. A vacuum is formed in the diffusion discharge pipe 142. The vacuum brings the gas which converges at the top of the inlet pipe 11 and in the inlet pipe line 3 of the centrifugal pump 2 into the diffusion discharge pipe 142 through the suction pipe 141. The medium which flows down from the spray plate 136 is mixed with the gas and is discharged from the discharge end of the inlet pipe 11 by the centrifugal pump 2. The original circuit and the suction pipe 141 together enhance the capacity of the gas-liquid mixed transportation and generate a greater pressure difference, which makes up for the deficiency of the existing external mixing type self-priming pump that the suction height is too low.

[0036] While the embodiments of the application have been illustrated and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the spirit and scope of the application, which is defined by the appended claims and their equivalents.

Claims

1. An external-mixing high-efficiency self-priming pump, characterized by: The centrifugal pump and the external mixing backflow device connected with the centrifugal pump are provided, the external mixing backflow device comprises an inlet pipe and a gas-liquid mixing tank, the outlet flange of the inlet pipe is connected with the inlet of the centrifugal pump, the inlet flange of the inlet pipe is connected with the inlet pipeline of the self-priming pump, one side of the gas-liquid mixing tank is communicated with the outlet of the centrifugal pump through a backflow pipe, the backflow valve capable of changing the switch state adaptively is arranged at the bottom outlet of the gas-liquid mixing tank, the diffuser discharge pipe assembly is arranged at the bottom end of the backflow valve, the diffuser discharge pipe assembly is communicated with the inlet pipe, and the gas-liquid mixing tank, the backflow valve and the diffuser discharge pipe assembly are connected into an integrated whole through the bolt B. The backflow valve comprises a sealing adjusting block arranged at the bottom end of the gas-liquid mixing tank, a bolt A arranged in the middle of the sealing adjusting block and a nut, a sealing plate, a spring and a jet plate which are sequentially sleeved on the outer wall of the bolt A from top to bottom, the jet plate is arranged in the lower part of the inner cavity of the sealing adjusting block through external threads, the threaded end of the bolt A extends out of the center position of the inner wall of the jet plate, penetrates the center position of the inner wall of the sealing plate and is connected with the nut through threads, and the bolt A can move up and down along the middle hole of the jet plate under the action of the spring elastic force and the medium pressure, the relative position of the sealing plate and the sealing adjusting block can be changed, so that the change of the switch state of the backflow valve is realized. The top surface of the jet plate is a conical surface, a plurality of through holes perpendicular to the conical surface are uniformly distributed on the conical surface, and the center lines of the plurality of through holes converge at a point. The diffuser discharge pipe assembly comprises a diffuser discharge pipe and a suction pipe, the diffuser discharge pipe has a pear-shaped structure with a thick upper part and a thin lower part, and the bottom part of the diffuser discharge pipe is communicated with the outlet end of the inlet pipe, one end of the suction pipe is communicated with the upper part of the diffuser discharge pipe, and the other end of the suction pipe is communicated with the top part of the inlet pipe near the inlet pipeline of the self-priming pump.

2. The outer-mixing type high-efficiency self-priming pump according to claim 1, characterized in that: The gas-liquid mixing tank comprises a tank body, a baffle arranged in the inner cavity of the tank body and a blocking plate arranged below the baffle, a water injection pipe is arranged at the bottom of one side of the outer wall of the tank body, a water injection cover is arranged at the top of the water injection pipe, and the blocking plate is arranged at the bottom of the other side of the tank body and communicated with the outlet of the centrifugal pump.

3. The outer-mixing type high-efficiency self-priming pump according to claim 2, characterized in that: A circular hole is arranged in the middle of the baffle, the baffle divides the tank body into two parts, and the two parts of the tank body are communicated through the hole in the middle of the baffle.

4. The outer-mixing type high-efficiency self-priming pump according to claim 2, characterized in that: The baffle is a spiral type and has an open circular arc shape.

5. The outer-mixing type high-efficiency self-priming pump according to claim 3, characterized in that: The baffle is lower than the bottom of the topmost pipeline of the inlet pipe to ensure that there is enough medium in the centrifugal pump, and the centrifugal pump can still operate normally even if the medium in the inlet pipeline is cut off.

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