CN106837887B - Liquid ejector with adjustable ejection parameters - Google Patents

Abstract

The invention discloses a liquid injection device with adjustable injection parameters. The centrifugal pump comprises a centrifugal pump body, an inlet flange pipe, an injection part, a throat pipe, an incidence cavity shell, a drainage pipeline, an injection angle adjusting mechanism and an injection length adjusting mechanism, wherein the centrifugal pump body, the inlet flange pipe, the injection part, the throat pipe, the incidence cavity shell, the drainage pipeline, the injection angle adjusting mechanism and the injection length adjusting mechanism are coaxially connected in sequence, the drainage pipeline comprises a flow adjusting valve, a horizontal drainage pipe and a flexible drainage pipe, the upper part of the centrifugal pump body is connected with the centrifugal pump diffusion pipe, the side part of the centrifugal pump diffusion pipe is connected with one end of the horizontal drainage pipe, the other end of the horizontal drainage pipe is connected with the incidence cavity shell through the flexible drainage pipe, the flexible drainage pipe is provided with the flow adjusting valve, the incidence cavity shell is connected to the injection part through the injection angle adjusting mechanism, and the throat pipe is connected with a pump inlet of the centrifugal pump body through the injection length adjusting mechanism. The invention can freely adjust the distance between the fluid injected by the injection device and the inlet of the impeller, the injection flow and the injection angle of the fluid, effectively avoid the occurrence of cavitation and improve the cavitation resistance of the centrifugal pump.

Description

Liquid injection device with adjustable injection parameters

technical field

The invention relates to the technical field of liquid conveying power equipment, in particular to a liquid ejection device with adjustable ejection parameters.

Background technique

The centrifugal pump is a kind of general-purpose machinery with a wide range of applications. During its operation, the absolute pressure at the impeller inlet will decrease. When the local pressure is lower than the local vaporization pressure, cavitation may occur. Cavitation not only degrades the performance of the centrifugal pump, but also causes a series of problems such as vibration and noise. In the past, the cavitation of centrifugal pumps was often avoided at the expense of speed, but the development of modern industry has made people have higher requirements for centrifugal pumps - high speed, low energy consumption, and economy, which inevitably caused the occurrence of cavitation .

In the prior art, one way to improve the anti-cavitation performance of the centrifugal pump is to install an ejector device at the outlet of the centrifugal pump, and use the ejector device to divert the high-pressure fluid at the outlet of the pump to the inlet of the impeller. The fluid supplements the low-pressure fluid with energy, so that the fluid pressure at the inlet of the impeller rises to avoid the occurrence of cavitation.

However, the length of the axial pipeline from the injection hole to the impeller inlet and the injection angle of the fluid in the existing centrifugal pump injection device are fixed, and under different working conditions, due to the different pressure compensation required, the distance from the injection hole to the impeller inlet The optimal length of the axial duct and the injection angle of the fluid are different. The inability to freely adjust the length and the injection angle of the fluid results in a small change in the pressure compensation of the high-pressure fluid entering the impeller inlet to the low-pressure fluid, which cannot effectively avoid the occurrence of cavitation and reduces the anti-cavitation performance of the centrifugal pump.

Contents of the invention

In view of the technical problems mentioned above in the background art, the present invention proposes a liquid injection device with adjustable injection parameters.

Technical scheme of the present invention is as follows:

The invention includes a centrifugal pump body, an inlet flange pipe, an injection part and a throat pipe connected in sequence coaxially, and an injection chamber shell installed outside the inlet flange pipe, a drainage pipeline, an injection angle adjustment mechanism and an injection length adjustment Mechanism, the drainage pipeline includes a flow regulating valve, a horizontal drainage tube and a flexible drainage tube. The upper part of the pump body of the centrifugal pump is connected to a centrifugal pump diffusion tube, and the side of the centrifugal pump diffusion tube is connected to one end of the horizontal drainage tube. The other end of the horizontal drainage tube passes through a flexible The drainage tube is connected to the injection cavity shell, and the flexible drainage tube is provided with a flow regulating valve. The injection cavity shell is connected to the injection part through the injection angle adjustment mechanism, and the throat is connected to the pump inlet of the centrifugal pump body through the injection length adjustment mechanism.

The injection angle of the fluid can be precisely adjusted and fixed through the injection angle adjustment mechanism of the present invention. The injection angle of the fluid can be flexibly adjusted through the injection angle adjustment mechanism of the present invention.

The pump body of the centrifugal pump is fixedly installed by the centrifugal pump base, and the impeller is arranged in the pump body of the centrifugal pump, and the impeller, the inlet flange pipe and the throat pipe are coaxially arranged.

The ejection length adjustment mechanism includes a pipe thread arranged on the outer peripheral surface of the throat, a connecting flange connected between the throat and the pump inlet of the centrifugal pump body, and a pump inlet casing, and the connecting flange is threaded on the Outside the pipe thread of the throat pipe, the connecting flange is fixedly connected to the flange end on the pump inlet so that the throat pipe is installed on the pump inlet of the centrifugal pump body. The inner peripheral surface of the pump inlet has a stepped hole, and the steps of the stepped hole and There is a pump inlet casing between the throat pipes for smooth connection between the inner wall of the pump inlet pipe and the inner wall of the throat pipe of the injection device; the installation position between the connecting flange and the throat pipe is adjusted through the thread, and then the throat pipe extends into the pump inlet The distance between the injection part connected to the back end of the throat and the pump inlet can be adjusted to achieve the injection length.

The injection part is a movable nozzle, and the movable nozzle includes a ring part and a plurality of straight pipes evenly distributed around the ring part, and the ring part is divided into a plurality of fixed segments uniformly distributed along the circumference and hinged between adjacent fixed segments The fixed section is fixedly connected between the inlet flange pipe and the throat pipe, and the two ends of the fixed section are respectively fixed and sealed with the end faces of the inlet flange pipe and the throat pipe. out into the throat.

The injection angle adjustment mechanism includes a rotating sleeve handle, a set screw, a nozzle support frame, a rotating sleeve, a threaded sleeve and a flange, and the other end of the straight pipe communicates with the injection cavity in the injection cavity shell through a flexible injection tube. , there is a threaded sleeve outside the inlet flange pipe, the front end of the threaded sleeve is connected to the other side of the straight pipe of the movable nozzle through the nozzle support frame; the rear end of the threaded sleeve is provided with a rotating sleeve through the threaded sleeve, and the inlet flange pipe The outer peripheral surface is provided with a flange for axially limiting and fixing the rotating sleeve. The rear end of the rotating sleeve is embedded with the flange through a hook groove so that it does not move in the axial direction but can rotate in the circumferential direction. Limiting rotating sleeve handle and set screw, the rotating sleeve handle is fixed on the outer peripheral surface of the rotating sleeve, used for the control of rotating the rotating sleeve, the set screw passes through the through hole on the side wall of the rotating sleeve to rotate the rotating sleeve The swivel sleeve is fixed.

The rotating sleeve and the threaded sleeve are connected by thread fit, and the threaded sleeve can only move axially along the pipe axis, while the rotating sleeve is installed on the flange and rotates around the center of the pipe, but cannot move axially. By rotating the rotating sleeve, the threaded sleeve is driven to move axially along the inlet flange tube, and then the straight tube of the movable nozzle is driven to change the direction of injection inward, so as to realize the adjustment of the injection angle.

Both the flexible incident tube and the flexible drainage tube are made of flexible materials, so that they can freely adapt to any injection angle of the fluid.

The movable nozzle is connected with the flexible injection pipe, and the outer surface of the movable nozzle is marked with scales, so that the size of the angle can be known conveniently.

The present invention adjusts the installation position between the connecting flange and the throat through threads, and then adjusts the distance from the throat to the pump inlet, so as to realize the adjustment of the ejection length between the ejection part connected to the rear end of the throat and the pump inlet; By rotating the rotating sleeve, the threaded sleeve is driven to move axially along the inlet flange pipe, and then the straight pipe of the movable nozzle is driven to change the direction of the inward ejection, so as to realize the adjustment of the ejection angle; the flow rate of the ejected fluid is changed by adjusting the flow regulating valve. In this way, the incident effect of the high-pressure fluid entering the impeller inlet is adjusted, so that the high-pressure fluid brought back can supplement the energy of the low-pressure fluid at the impeller inlet, fully ensuring that the liquid pressure is higher than the vaporization pressure of the liquid itself, and avoiding the occurrence of cavitation. Effectively improve the anti-cavitation performance of the centrifugal pump.

The beneficial effects of the present invention are:

The invention can freely adjust the distance between the fluid ejected by the ejector device and the inlet of the impeller, the ejected flow rate and the ejected angle of the fluid, can effectively avoid the cavitation phenomenon, and improve the anti-cavitation performance of the centrifugal pump.

Description of drawings

Fig. 1 is the structural representation of the embodiment of the present invention;

Fig. 2 is the cross-sectional structure schematic diagram of the embodiment of the present invention;

Fig. 3 is a structural schematic diagram of the ejection angle adjustment mechanism;

Fig. 4 is a schematic cross-sectional structure diagram of the ejection angle adjustment mechanism.

Fig. 5 is a schematic diagram of the state of ejection length adjustment.

In the figure: inlet flange tube 1, injection cavity shell 2, rotating sleeve handle 3, movable nozzle 4, ring part 41, straight pipe 42, fixed section 43, movable section 44, pipe thread 5, pump inlet 6, centrifugal pump Base 7, centrifugal pump body 8, centrifugal pump diffuser tube 9, centrifugal pump outlet 10, horizontal drainage tube 11, flow regulating valve 12, connecting flange 13, flexible incident tube 14, flexible drainage tube 15, set screw 16, Pump inlet casing 17, throat pipe 18, incident cavity 19, nozzle support frame 20, rotating sleeve 21, threaded sleeve 22, flange 23, impeller 24.

Detailed ways

The specific embodiments of the present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1, the specific implementation of the present invention includes a centrifugal pump body 8, an inlet flange pipe 1, an injection part and a throat pipe 18, and an entrance chamber shell 2 installed outside the inlet flange pipe 1, which are sequentially connected coaxially. Drainage pipeline, injection angle adjustment mechanism and injection length adjustment mechanism, the centrifugal pump body 8 is fixedly installed through the centrifugal pump base 7, the centrifugal pump body 8 is provided with an impeller 24, the impeller 24, the inlet flange pipe 1 and the throat pipe 18 coaxial arrangement. The inlet end of the inlet flange pipe 1 is connected to the liquid, the outlet end is connected with the inlet end of the throat pipe 18 through the injection part, and the outlet end of the throat pipe 18 is connected with the pump inlet 6 of the centrifugal pump body 8 through the connecting flange 13 .

As shown in Figure 1, the drainage pipeline includes a flow regulating valve 12, a horizontal drainage pipe 11 and a flexible drainage pipe 15. The upper part of the centrifugal pump body 8 is connected with a centrifugal pump diffusion pipe 9, and the side of the centrifugal pump diffusion pipe 9 is connected with a horizontal drainage pipe. One end of the horizontal drainage tube 11 and the other end of the horizontal drainage tube 11 are connected to the injection cavity shell 2 through the flexible drainage tube 15. The flexible drainage tube 15 is provided with a flow regulating valve 12, which regulates the ejection flow by controlling the valve. The incident cavity shell 2 is connected to the injection part through the injection angle adjustment mechanism, and the throat pipe 18 is connected to the pump inlet 6 of the centrifugal pump body 8 through the injection length adjustment mechanism.

As shown in Figures 1 and 2, the ejection length adjustment mechanism includes a pipe thread 5 arranged on the outer peripheral surface of the throat pipe 18, a connecting flange 13 connected between the throat pipe 18 and the pump inlet 6 of the pump body 8 of the centrifugal pump, and The pump inlet casing 17, the connecting flange 13 is threaded on the outside of the pipe thread 5 of the throat pipe 18, and the connecting flange 13 is fixedly connected with the flange end on the pump inlet 6 so that the throat pipe 18 is installed on the pump body of the centrifugal pump 8. The pump inlet 6 has a stepped hole on the inner peripheral surface of the pump inlet 6, and a pump inlet casing 17 is provided between the step of the stepped hole and the throat pipe 18; the installation between the connecting flange 13 and the throat pipe 18 is adjusted by thread Position, and then adjust the distance from the throat pipe 18 to the pump inlet 6, so as to realize the adjustment of the ejection length between the ejection part connected to the rear end of the throat pipe 18 and the pump inlet 6.

As shown in Figure 3, the injection part is a movable nozzle 4, and the movable nozzle 4 includes a ring portion 41 and a plurality of straight pipes 42 that are evenly distributed around the ring portion 41. The outer surface of the ring portion 41 is marked with scales, and the ring portion 41 points It is a plurality of fixed sections 43 uniformly distributed along the circumference and a movable section 44 hinged between adjacent fixed sections 43. The fixed section 43 is fixedly connected between the inlet flange pipe 1 and the throat pipe 18. The two ends of the fixed section 43 are respectively It is fixed and sealed with the end faces of the inlet flange pipe 1 and the throat pipe 18. The movable section 44 can rotate around its own axis (that is, the tangential direction of its circumference). One end of the straight pipe 42 is fixedly inserted into the movable section 44 and passes through the movable section 44. Out into the throat pipe 18, the straight pipe 42 is fixedly connected with the movable section 44.

As shown in Figures 3 and 4, the injection angle adjustment mechanism includes a rotating sleeve handle 3, a set screw 16, a nozzle support frame 20, a rotating sleeve 21, a threaded sleeve 22 and a flange 23, and the other end of the straight pipe 42 The flexible incident tube 14 is connected to the incident cavity 19 in the incident cavity shell 2, and the incident cavity 19 is fixedly installed outside the inlet flange tube 1 through a mounting bracket. The front end of the barrel 22 is connected to the other side of the straight pipe 42 of the movable nozzle 4 through the nozzle support frame 20; One end is fixedly connected with the threaded sleeve 22 . The rear end of the threaded sleeve 22 is threaded with a rotating sleeve 21, and the outer peripheral surface of the inlet flange pipe 1 is provided with a flange 23 for axially limiting and fixing the rotating sleeve 21. The edge 23 is embedded to realize that the axial direction does not move but the circumferential direction can rotate. The rotating sleeve handle 3 and the set screw 16 for rotation and rotation limit are installed outside the rotating sleeve 21, and the rotating sleeve handle 3 is fixed on the rotating sleeve 21. The outer peripheral surface is used to control the rotation of the rotating sleeve 21 , and the set screw 16 passes through the through hole of the side wall of the rotating sleeve 21 to fix the rotating sleeve 21 after rotation.

Working process of the present invention is as follows:

The conveyed fluid medium passes through the inlet flange pipe, flows through the throat pipe and the pump inlet, and is sucked into the pump body. The high-speed rotation of the impeller in the pump body acts on the fluid, and the high-pressure fluid with high energy characteristics is transmitted in the diffuser pipe, and passed through the centrifugal pump. The pump outlet delivers to the destination.

Specifically, by rotating the screw thread and installing a pump inlet sleeve 17 with different lengths at the pump inlet, the distance of the injection part extending into the pump inlet 6 is controlled to realize the adjustment of the distance between the fluid ejected by the injection part and the impeller inlet, as shown in the figure 2 adjusted to Figure 5.

By turning the rotating sleeve 21 to drive the threaded sleeve 22 to move axially along the inlet flange tube 1, and then driving the straight tube 42 of the movable nozzle 4 to change the direction of the inward emission, the adjustment of the injection angle is realized.

When the injection angle of the fluid needs to be changed, the rotating handle can make the rotating sleeve 21 drive the threaded sleeve 22 to move axially, so that the nozzle support frame 20 drives the straight pipe 42 on the movable nozzle 4 to rotate, and the flexible injection pipe 14 can Adapt to meet the angle adjustment of movable nozzle 4 at any time.

When the position of the movable nozzle 4 is at the desired angular position, tighten the set screw 16 on the rotating sleeve 21 to prevent the angle of the nozzle from changing, and the flexible incident tube 14 can meet the angle adjustment of the movable nozzle 4 at any time to realize fluid flow. Precise adjustment of the ejection angle.

A flow regulating valve 12 is designed on the horizontal drainage pipe 11. By controlling the flow regulating valve 12, the injection flow can be adjusted to compensate the low-pressure and low-energy fluid at the inlet of the impeller, so as to avoid the occurrence of cavitation and improve the flow rate as much as possible. Anti-cavitation performance of centrifugal pumps.

The drainage pipe in the ejection device of the present invention guides a part of the high-pressure fluid in the diffusion pipe through the horizontal drainage pipe, the flow regulating valve and the flexible drainage pipe in turn, and then leads it back into the injection cavity, and passes through the evenly arranged fluid connected to the injection cavity. A plurality of flexible injection pipes lead the high-pressure fluid to the movable nozzle, and the high-pressure fluid is sprayed to the throat through the movable nozzle, and the flow of the high-pressure fluid is stabilized through the throat, and finally the high-pressure fluid reaches the impeller inlet of the pump body stably, thereby controlling the inflow The low-pressure fluid at the inlet of the impeller supplements energy, eliminates or weakens the cavitation phenomenon at the inlet of the impeller, and improves the anti-cavitation performance of the centrifugal pump.

When it is necessary to change the working conditions of the centrifugal pump, such as increasing the speed of the centrifugal pump, by adjusting the ejection length between the ejection part connected to the rear end of the throat and the pump inlet; by adjusting the ejection angle of the fluid; by adjusting the flow rate The regulating valve varies the flow of ejected fluid. The incident effect when the high-pressure fluid enters the impeller inlet can be adjusted, and the anti-cavitation performance of the centrifugal pump can be improved more effectively.

Claims (6)

1. A liquid injection device with adjustable injection parameters, characterized in that: it includes a centrifugal pump body (8), an inlet flange (1), an injection component and a throat (18) connected coaxially in sequence And the entrance chamber shell (2), the drainage pipe, the injection angle adjustment mechanism and the injection length adjustment mechanism installed outside the inlet flange pipe (1), the drainage pipeline includes a flow regulating valve (12), a horizontal drainage tube (11) and the flexible drainage tube (15), the centrifugal pump body (8) top is connected with a centrifugal pump diffusion tube (9), the side of the centrifugal pump diffusion tube (9) is connected to one end of the horizontal drainage tube (11), and the horizontal drainage tube ( 11) The other end is connected to the injection cavity shell (2) through the flexible drainage tube (15). The flexible drainage tube (15) is provided with a flow regulating valve (12), and the injection cavity shell (2) is connected to the injection cavity through the injection angle adjustment mechanism. The ejection part, the throat pipe (18) is connected with the pump inlet (6) of the pump body (8) of the centrifugal pump through the ejection length adjustment mechanism; Described injection part is movable shower head (4), and movable shower head (4) comprises ring portion (41) and a plurality of straight pipes (42) that are evenly connected around ring portion (41), and ring portion (41) divides It is a plurality of fixed segments (43) uniformly distributed along the circumference and a movable segment (44) hinged between adjacent fixed segments (43), the fixed segment (43) is fixedly connected between the inlet flange pipe (1) and the throat pipe (18), the two ends of the fixed section (43) are respectively fixed and sealed with the end faces of the inlet flange (1) and the throat (18), and one end of the straight pipe (42) is fixedly inserted into the movable section (44). The active section (44) passes through the throat (18); The injection angle adjustment mechanism includes a rotating sleeve handle (3), a set screw (16), a nozzle support frame (20), a rotating sleeve (21), a threaded sleeve (22) and a flange (23), The other end of the straight pipe (42) is connected to the incident cavity (19) in the incident cavity shell (2) through the flexible incident tube (14). The front end of the sleeve (22) is connected to the other end side of the straight pipe (42) of the movable nozzle (4) through the nozzle support frame (20); the rear end of the threaded sleeve (22) is threaded with a rotating sleeve (21), The outer peripheral surface of the inlet flange pipe (1) is provided with a flange (23) for axially limiting and fixing the rotating sleeve (21), and the rear end of the rotating sleeve (21) is embedded with the flange (23) through a hook groove , a rotating sleeve handle (3) and a set screw (16) for rotation and rotation limiting are installed outside the rotating sleeve (21). 2. A liquid injection device with adjustable injection parameters according to claim 1, characterized in that: the centrifugal pump body (8) is fixedly installed by the centrifugal pump base (7), and the centrifugal pump body (8) is provided with impeller (24) inside, and impeller (24), inlet flange pipe (1) and throat pipe (18) are coaxially arranged. 3. A liquid ejection device with adjustable ejection parameters according to claim 1, characterized in that: said ejection length adjustment mechanism includes pipe threads (5) arranged on the outer peripheral surface of the throat (18) ), the connecting flange (13) connected between the throat pipe (18) and the pump inlet (6) of the centrifugal pump body (8), and the pump inlet sleeve (17), the connecting flange (13) passes through the threaded sleeve Outside the pipe thread (5) of the throat (18), the connecting flange (13) is fixedly connected with the flange end on the pump inlet (6) so that the throat (18) is installed on the pump body (8) of the centrifugal pump At the pump inlet (6), there is a stepped hole on the inner peripheral surface of the pump inlet (6), and there is a gap between the step of the stepped hole and the throat (18) for smoothly connecting the inner wall of the pump inlet pipe and the inner wall of the throat of the ejector device. The pump inlet casing (17); adjust the installation position between the connecting flange (13) and the throat (18) through threads, and then adjust the distance between the throat (18) and the pump inlet (6), so that the throat (18) The ejection length adjustment between the ejection part connected to the rear end and the pump inlet (6). 4. A liquid injection device with adjustable injection parameters according to claim 1, characterized in that: by rotating the rotating sleeve (21), the threaded sleeve (22) is driven along the axis of the inlet flange tube (1). To move, and then drive the straight pipe (42) of the movable nozzle (4) to change the direction of the inward emission, so as to realize the adjustment of the injection angle. 5. The liquid injection device with adjustable injection parameters according to claim 1, characterized in that: the flexible incident tube (14) and the flexible drainage tube (15) are both made of flexible materials. 6. A liquid injection device with adjustable injection parameters according to claim 1, characterized in that: the movable nozzle (4) is connected to the flexible injection pipe (14), and the outer surface of the movable nozzle (4) Marked with scale.

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