RU2621193C2 - Submersible grounding centrifugal pump - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: precoat submersible centrifugal pump comprises an impeller with blades, provided with a drive housing (3) with attached thereto the main outlet pipe (5) and the additional output pipes (6, 7) provided with flaps (8). The housing (3) includes an impeller with minimal radial clearance. At its inlet (15) mounted inlet oriented in the meridional cross section in the main pipe (5). Additional nozzles (6, 7) are arranged in a first of the main pipe (5) half shell (9) of the housing (3) according to the rotational direction of the impeller 1.

EFFECT: increase of the pump upon removing the soil by increasing the intensity of the loosening process.

5 cl, 12 dwg

Description

The invention relates to pump engineering and can be used in centrifugal low-pressure soil pumps used in the treatment, land reclamation, for the extraction of sapropel, non-metallic building materials, etc., that is, work performed by a hydromechanized method.

A known pump with a centrifugal wheel made in the form of a flat disk with radial working channels of cylindrical shape, made partially open along the generatrix on one of the sides of the disk, the second wall of the outlet channel being located tangent to the generatrices of working channels (A. S. USSR No. 620674, C. F04D 29/18, publ. 08/25/1978., bull. No. 31). The centrifugal pump design under consideration, due to the use of a half-open impeller, additionally has a radial fluid twist, which leads to an increased head coefficient in the local annular part of the outlet covering the wheel in the plane where the peripheral speed of the rotating wheel coincides in the direction and the peripheral speed of the fluid in the radial channel of the wheel . However, due to the complex configuration of the impeller, difficulties in carrying out the necessary cleaning measures for the flow part of the wheel, this pump is unsuitable for work on soils with lumpy inclusions and vegetation.

The closest technical solution to the claimed is a centrifugal pump for the preparation and pumping of suspensions, containing an impeller, a housing with a pressure head and at least one additional tangentially located nozzle, equipped with a nozzle and a gate, providing an intensification of the process of preparing the suspension due to the recirculation action of the jet from mixtures for the initial product (A. p. No. 511435, class F04D 7/04, publ. 04/25/1975., bull. No. 15).

The ripping jets from the mixture have a higher density with respect to water, and hence greater kinetic energy, which provides a high loosening ability. However, the speed of this jet does not exceed the value of the peripheral component of the velocity at the exit of the wheel, that is, the pressure in the ripping nozzles does not exceed the value of the pressure in the discharge, which is a limitation of a further increase in the ripping ability of this ripping device.

Under the conditions of performing sewage treatment works on land reclamation systems and utility structures, as well as when extracting sapropel in the form of a mixture from the bottom of natural reservoirs, a reasonable and sufficient pressure value for transportation is 8-14 meters of water column. The required pressure in the ripping pipes for the effective impact of the jet on the ground should be at least 20 meters of water column.

The increase in pressure in the rip nozzles by increasing the speed of the impeller leads to a decrease in efficiency and an increase in power consumption, which forces either to unreasonably increase the drive power, or if there is a limitation on the installed power, to separate the functions of loosening and discharge in time, which reduces the productivity of the overall process.

The installation of an additional special pump or several pumps with the required performance for working on the loosening pipes significantly complicates the design, reduces reliability, increases the cost, weight of the device.

Moreover, in the prototype, all nozzles work simultaneously, which leads to a significant drop in the specific energy of the loosening liquid on each nozzle - in this case, the principle of energy compaction is not observed and the necessary level of loosening ability of each of the jets will not be obtained.

In addition, each of the jets moves in its own independent direction, in this case the effect of interaction of the jets is not used, that is, there is a shortfall in the performance of the device.

The aim of the invention is to increase the productivity of a submersible soil centrifugal pump on the recoverable soil by increasing the intensity of the process of cultivation.

To achieve this goal in a known centrifugal pump for the preparation and pumping of suspensions containing an impeller with blades, equipped with a drive, a housing with a central inlet, as well as with a main and several additional outlet pipes equipped with dampers, the housing covers the impeller with minimum radial clearance, an inlet pipe is installed on its inlet, oriented in the meridional section in the direction of the main outlet, and additional nozzles are placed in the first from the main half of the shell shell in the direction of rotation of the impeller;

wherein:

- the impeller blades are made radial;

- the inlet pipe is rotatable relative to the axis of the inlet and is provided with a rotary drive connected by negative feedback to the impeller drive, made, for example, in the form of a hydraulic cylinder fed from a discharge branch of the impeller drive hydraulic motor and a counteracting return spring;

- each of the dampers is made in the form of a cantilever swinging part of the shell of the housing, and they are interconnected by levers through the hydraulic cylinder of the drive.

The implementation of the pump housing covering the impeller with a minimum radial clearance ensures the exclusion of the meridional flow on most of the outer circumference of the impeller and, therefore, its significant amplification on a smaller arc covered by the main discharge pipe (Fig. 1). The liquid dispersed in this sector of the housing has a speed comparable to the flow rate. At the next moment, that is, when the tongue formed by the inner surface of the shell of the body and the main outlet pipe passes through the interscapular channel, the flow moving through the wheel grill is blocked on five sides. There is a water hammer and an increase in pressure proportional to the density of the liquid and the value of the flow rate. This pressure is an increment to the pressure from the impact on the same interscapular volume of the liquid of the impeller blades, as a result, a pressure greater than the pressure in the main outlet pipe occurs at the local point of the shell shell.

The execution of the impeller blades radial, firstly, does not allow each of them to be located across the flow at the time of passage of the discharge pipe. Secondly, in this case, there is still an additional flow due to flow separation from the back of the blade when it rotates in the flow (meridional) flow after it passes through the sector covered by the main outlet pipe (Fig. 2). In the separation zone behind the blade, a return flow forms, which, as the blade moves behind the tongue, increases its volume and increases the intensity from friction against the flow rate. Thirdly, the locked interscapular volume in this case is closer to the spherical shape, therefore, the fragment above the marked flow at the moment of passage of the body language will continue to move along circular paths, and at the periphery in the direction of rotation of the impeller.

These circumstances cause the addition of peripheral speeds in the area of the first half of the shell of the housing from the main outlet pipe in the direction of rotation of the impeller. The first vector is due to the rotation of the impeller and is its peripheral speed, the second is the rotation of the interscapular volume itself in the form of a satellite vortex, which causes a pressure peak in this part of the shell.

At the same time, the organization of the input flow in the direction of the main outlet pipe (Fig. 3), as well as its orientation, by turning the inlet pipe in the plane of rotation of the impeller, towards the movement of the blades (Fig. 4, Fig. . 5).

As a result of the proposed measures, a pulsating pressure can be created in the indicated section of the housing, the value of which will exceed the pressure in the main discharge pipe, and also control its value.

The established facts will allow, on the basis of a low-pressure pump (H = 14 m), to create a high-pressure (N = 20 m) hydrotreating system by installing an additional outlet pipe in the indicated zone.

It is advisable to install not one additional output pipe, but two interconnected ones, which will allow, firstly, to use the effect of the interaction of the jets (Fig. 6). That is, the first stream loosens in its direction, producing a face, the second stream, turning on with a time delay, develops its face and for a long range parallel to the line of action of the first jet, etc. .. At the same time, the whole pillar of soil located between the lines of action of the jets , each time breaking off, it is absorbed by a piece into the pump, and additional erosion power is not expended on its grinding.

Secondly, the alternate operation of the additional outlet pipes does not cause a significant drop in the specific energy of the loosening liquid on each nozzle, therefore, the necessary level of loosening ability of each of the jets will be obtained.

Thirdly, the inclusion of each subsequent pipe assumes its maximum approximation to the front of loosening, which leads to the use for loosening of a more active and more concentrated initial portion of the jet of loosening liquid.

Fourth, in this case, the effect of impact on the array of the underwater soil under development is used, which implies its instant destruction into lump fragments.

The degree of saturation of the mixture with soil determines the torque on the impeller shaft of the pump, and the saturation itself is determined by the intensity of the ripping jets from the additional outlet pipes, which in turn depends, for example, on the orientation of the inlet pipe (Fig. 4). This set of circumstances is a prerequisite for the creation of an adaptive hydraulic loosening system. It is tuned to a predetermined level of productivity on the ground by making the inlet pipe rotatable relative to the axis of the inlet and supplying it with a rotary drive connected by negative feedback to the impeller drive, made, for example, in the form of a hydraulic cylinder fed from the discharge branch of the pump impeller hydraulic motor and counteracting return spring.

In this case, the mixture that is excessively saturated with soil will entail an increase in pressure in the discharge branch of the impeller drive hydraulic motor, and hence on the swing hydraulic cylinder, which will turn the inlet pipe relative to the housing, overcoming the force of the counteracting return spring * following the moving blades. The intensity of the ripping jets will weaken, the mixture formation process will slow down, the density of the mixture will decrease to the required limit, which will exclude the possibility of clogging the slurry pipeline.

When the mixture is lean, the opposing return spring, overcoming less pressure in the hydraulic cylinder, rotates the inlet pipe relative to the housing towards the movement of the blades and the intensity of the jets from the additional output pipes increases. Therefore, with a constant power rating, its entire resource is completely redistributed between the loosening and transporting abilities of the working body, and its adaptation can occur under changing operating conditions.

The design of each of the dampers in the form of a cantilever swinging part of the shell of the housing:

- provides movement of the loosening fluid from the body along smooth paths and therefore low hydraulic resistance of each of the loosening jets;

- helps to restore the passage sections of the channel of each of the additional output pipes in the open-close mode when clogging with lumpy inclusions;

- simplifies the design of the pipe.

The establishment of communication between the closing elements of the additional outlet pipes, that is, the cantilever swinging parts of the shell, through levers and a hydraulic cylinder provides an alternative mode of operation of the pipes, which is expressed in the mandatory opening of one pipe with the second closed and vice versa.

The proposed technical solution is illustrated by the drawings:

FIG. 1. Scheme of the meridional flow in the area of the housing, covered by the main outlet pipe.

FIG. 2. Scheme of the formation of the return flow in the separation region behind the back of the scapula passing the body language.

FIG. 3. Scheme of interaction of the input stream with the impeller blade passing through the body language.

FIG. 4. Scheme for controlling the intensity of interaction of the input stream with a blade passing through the body language.

FIG. 5. Visualization of the satellite vortex by the deviation of silk silk pasted on the disk of the impeller.

FIG. 6. Phase cycle of two alternately working jets.

FIG. 7. Front view of a submersible submersible centrifugal pump with the second auxiliary output open (the hydraulic drive cylinder of the additional output nozzles is compressed).

FIG. 8. Side view of a submersible submersible centrifugal pump (the hydraulic cylinder of the drive for additional output pipes has been removed).

FIG. 9. Axonometric image of the system of additional ripping pipes (the hydraulic cylinder of the drive of additional output pipes is conventionally removed).

FIG. 10. Front view of a submersible submersible centrifugal pump with the first additional output pipe open (the hydraulic drive cylinder of the pipe is unclenched) with the inlet pipe control system - a situation of low saturation of the pulp with soil.

FIG. 11. Front view of a submersible soil centrifugal pump with the first additional nozzle open (the hydraulic drive cylinder of the nozzles is unclenched) with the inlet nozzle control system - a situation of high saturation of the pulp with soil.

FIG. 12. A prototype submersible soil centrifugal pump.

Submersible soil centrifugal pump consists of an impeller 1 with radial blades 2, housing 3 in the form of a hollow cylinder with inlet 4, main outlet 5, and two 6, 7 additional outlet pipes.

The peripheral wall 8 (Fig. 8, Fig. 9) of each of the additional outlet pipes 6 and 7 (Fig. 7, Fig. 10, Fig. 11) is made in the form of a triangular part of the shell 9 of the housing 3 cantilever swinging on a hinged cylindrical support 10 s the ability to occupy fixed positions: the first - coinciding with the shell, and the second - deflected outward with the formation of a selective channel for flow q. Ensuring fixation in the second position of the peripheral wall and the completion of each selective channel is carried out by an edge 11, which is installed along the cut line of the movable peripheral wall 8 on the shell 9 of the housing 3, perpendicular to it. Each of the peripheral walls 8 is provided with a lever 12 or 13, which are interconnected by an actuating hydraulic cylinder 14 (Fig. 7, Fig. 10, Fig. 11, not shown in Fig. 9). In addition, diffuser-type nozzles can be installed on the end of each of the movable peripheral walls or on the front surface of the housing to give direction to the ripping flow (not shown in the figures).

The inlet pipe 4 at the inlet Central hole 15 in the front wall of the housing 3 is mounted pivotally (Fig. 8), for which its mating part is equipped with a flange 16 and a sleeve clip 17, mounted on the pump housing 3, for example, with pins. In this case, the inlet pipe 4 through the lever 18 is connected to the drive, made in the form of a hydraulic cylinder of rotation 19 and the return spring 20 opposing it (Fig. 11, Fig. 10). The discharge cavity of the turning cylinder 19 is connected with the discharge line 21 of the hydraulic motor 22 of the impeller 1. The drain branches of the hydraulic motor 22 and the turning cylinder 19 are also combined. The hydraulic motor of the drive 22 is connected with the impeller of the pump by a shaft 23.

For the operation of a submersible soil centrifugal pump in a system with other links of the functional circuit, a slurry pipe 24 is connected to the main output pipe 5 of the pump.

The operation of a submersible soil centrifugal pump is as follows.

The device is under water. When the impeller 1 rotates from the hydraulic motor 22 through the shaft 23 under the action of the blades 2, the water in the housing 3 comes into rotational motion, causing the appearance of a centrifugal force, which causes the creation of pressure, amplifying to the periphery of the rotating volume. Due to the pressure difference in the slurry line and the peripheral part of the wheel, the fluid moves into the slurry line 24 through the main outlet pipe 5. Due to the central volumes of the housing 3 released from the liquid, a vacuum is created in it, which also leads to a pressure difference at the inlet and outlet of the inlet pipe 4. As a result , a fluid flow is formed from the outer space into the inlet pipe 4, the impeller 1 of the pump, the main outlet pipe 5, the slurry pipe 24.

In order for the submersible soil centrifugal pump to pump the water-soil mixture, it should be prepared by exposing the ripping jets to the developed soil pool.

In this case, the execution of the housing 3 covering the impeller 1 with a minimum radial clearance eliminates the meridional overflow on most of the outer circumference of the wheel 1 and, thereby, its significant amplification on the arc covered by the main output pipe 5 (Fig. 1). Moreover, during the passage by the interscapular channel of the wheel 1 of the arc covered by the discharge pipe 5, firstly, the liquid participates in the return flow in the separation zone, from the back of the blade, due to the rotation of the blade in the flow stream (Fig. 1, position 3). Secondly, this return flow is enhanced by shielding this zone with the tongue of the main outlet pipe 5 and by increasing the flow when the working surface of the subsequent blade approaches the tongue (Fig. 2). Thirdly, on the arc after the tongue, the inlet edge of the blade 2 runs onto the input stream from the inlet pipe 4, part of which continues to move along the working side of the blade 2 with the summation of the flow rates and the blade (Fig. 3).

All these circumstances cause the formation of an intense vortex flow (Fig. 5) in the interscapular channel, and on the periphery in the direction of rotation of the impeller 1. On the arc (Fig. 3)

,

,

where z is the number of blades;

D ₁ - the diameter of the input edges of the impeller blades;

D ₂ - the outer diameter of the impeller,

housing 1 after the tongue of the main outlet 5, the fluid is ahead of the wheel 1, therefore, in this zone the pressure exceeds the pressure in the main outlet 5.

On this section of the shell are placed two alternately working additional output pipes 6 and 7 (Fig. 7, Fig. 8, Fig. 9, Fig. 10, Fig. 11), through which the flow rate of the loosening fluid is greatest with respect to the entire pump. The control drive for these pipes 6, 7, including a hydraulic cylinder 14, levers 12, 13, shutters 8 in the form of a part of the shell 9 and fastened with hinges 10 on it with the possibility of swing allows you to alternatively close and open each of them. In this case, when the hydraulic cylinder 14 is open (Fig. 9, Fig. 10, Fig. 11), the pipe 7 is open, the lower pipe 6 is closed, and vice versa, when the lower 6 is compressed, the upper 7 is closed (Fig. 7). The hydraulic cylinder 14 of the nozzles 6, 7 can be controlled either manually from the operator's cab, or using the unit relay and the electromagnetic control valve automatically. This mode of operation of the ripping, that is, additional outlet pipes, corresponds to the technological scheme depicted in FIG. 6, with the above advantages. In addition, there is a position of the hydraulic cylinder 14, in which both additional output pipes are open, which allows you to use, if necessary, the third mode with the simultaneous operation of both additional output pipes.

In this case, an increase in the rotation intensity of the interscapular volume will also be facilitated by the organization of the input flow in the direction of the main outlet pipe 5 in the meridional section (Fig. 3), as well as its orientation, by turning the outlet pipe 4, towards the movement of the blades 2 in the plane of rotation of the impeller 1 (Fig. 4). That is, in order to provide additional intensification of the loosening flows, the additional inlet pipe 4 through the lever 18 should be turned by the hydraulic cylinder 19 to the required angle 0.

However, an excessive increase in loosening capacity can redistribute the power balance to the detriment of the pumping capacity. To prevent this situation, the cylinder rod 19 is equipped with a counteracting return spring 20, the rigidity of which is selected sufficient to compensate for the pressure in the discharge branch of the hydraulic motor 22 of the impeller 1. In this case, saturation of the mixture with soil will increase the torque on the shaft 23 of the impeller 1. Therefore, it will increase and pressure in the discharge branch 21 of the hydraulic drive of the impeller 1, which is connected with the working cavity of the hydraulic cylinder 19. The increased pressure in the product by the piston area of the guide of logs 19 overcomes the force of the return spring 20 and rotates the inlet 4 via the lever 18 in a position corresponding to at ripper ability (Fig. 10). The density of the mixture decreases and the pump operates in the normal optimal mode.

When the submersible submersible centrifugal pump is running in lean mode, the density is minimal, the pressure in the drive hydraulic system, and therefore in the turning hydraulic cylinder 19, is minimal. The force of the return spring 20 through the lever 18 turns the suction pipe 4 into the high-intensity position of the ripping jets (Fig. 11).

The adjustment of the operating mode of the suction pipe 4 can also be carried out from the operator's cab, provided that additional shut-off regulatory equipment is installed on the hydraulic system of the cylinder 19 for turning the inlet pipe 4.

The proposed technical solution has significant advantages compared to many analogues and prototype: it has less energy consumption when developing soils due to the pulsed action of a concentrated water-soil jet on the array being developed, as well as using the technology of interaction of loosening jets, it has a high ability to develop dense soils due to the high discharge pressure of each of the ripping jets, achieved by installing the impeller with a minimum radial clearance rum in a cylindrical pump housing and install additional outlet connections to the high-pressure portion of the shell casing.

These advantages contribute to increasing the productivity of the solid component, due to the high consistency of the pumped water-soil mixture (the achieved soil concentration in the mixture during testing of the manufactured prototype (Fig. 12) of the device exceeded 40%), as well as improving the quality of cleaning of household reservoirs with dense caked sediment.

Claims (5)

1. A submersible soil centrifugal pump containing an impeller with vanes, equipped with a drive, a housing with a central inlet, and also with a main and several additional outlet pipes equipped with dampers, characterized in that the housing covers the impeller with a minimum radial a gap, an inlet pipe is installed on its inlet, oriented in the meridional section in the direction of the main outlet, and additional nozzles are placed in the first the main half of the shell in the direction of rotation of the impeller. 2. Submersible soil centrifugal pump according to claim 1, characterized in that the impeller vanes are made radial. 3. Submersible soil centrifugal pump according to claim 1, characterized in that the inlet pipe is made with the possibility of rotation relative to the axis of the inlet. 4. Submersible submersible centrifugal pump according to claim 1, characterized in that each of the dampers is made in the form of a cantilever swinging part of the shell of the housing and they are connected by levers through the hydraulic cylinder of the drive. 5. The submersible submersible centrifugal pump according to claim 1, characterized in that the inlet pipe is equipped with a rotary drive connected by negative feedback to the impeller drive, made, for example, in the form of a hydraulic cylinder, fed from the discharge branch of the impeller drive hydraulic motor and an opposing return spring .

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