WO2020013729A1

WO2020013729A1 - Centrifugal pump

Info

Publication number: WO2020013729A1
Application number: PCT/RU2019/000331
Authority: WO
Inventors: Andrey Yurievich YAZYKOV
Original assignee: Yazykov Andrey Yurievich
Priority date: 2018-07-10
Filing date: 2019-05-13
Publication date: 2020-01-16
Also published as: EA038211B1; EA202000217A1; RU2683062C1; EP3821131A1; EP3821131A4

Abstract

A centrifugal pump contains an impeller mounted in a housing, inlet and discharge chambers of the pumped medium, a jet ejector device with an inlet channel for supplying the medium from the chamber to the impeller, a nozzle, a tube and a channel. The nozzle is installed in alignment with the channel and connected to the chamber with its inlet. The tube is arranged in the chamber. The pump has a valve made with a seat and a spring-mounted and membrane-fixed shut-off control element. In the housing, a bypass channel is made hydraulically parallel to the nozzle. The flow-type control cavity is formed by the membrane and connected to the chamber with through holes and, and to the inlet nozzle. The valve seat is made on the edge of the bypass channel. The invention is designed to decrease the size and weight of the pump through optimum implementation of the valve and nozzle.

Description

Centrifugal pump

Field of the Invention

The invention relates to the field of the machine-building industry, in particular to the vane pumps for supplying water for domestic or industrial purposes.

Prior Art

Centrifugal pumps with a jet ejector device that provides pump start up and self-suction while running are known.

In particular, centrifugal pumps with jet ejector device SU 108211, SU 234868, SU 1021819, US 2484105, US 2524770, EP 0401670, EP 0361329 are known.

Each known centrifugal pump has a fixed head-capacity curve which is the main aspect when choosing a pump for the water supply system. However, even the most optimal selection of the pump does not exclude pressure drops at varying output, due to the inverse relationship of these parameters in the centrifugal pump. In actual practice, this results in deviations from the comfortable pressure value when opening or closing additional water points (sink and shower taps, etc.) and necessitates manual control of the comfort mode.

The closest analogous solution to the claimed device is a centrifugal pump containing the shaft-mounted impeller in the housing, inlet and discharge chambers of the pumped medium, as well as a jet ejector device with an inlet channel for supplying the pumped medium from the inlet chamber to the impeller, and with the inlet operating nozzle installed in alignment with the above inlet channel and connected to the discharge chamber with its own inlet, as well as the valve made with the seat and the spring-mounted and membrane-fixed shut-off control element for regulating the flow of the pumped medium injected through the nozzle of the ejector device (SU 108211, prototype).

The disadvantageous feature of the closest analogue is the large size and weight, as well as the significant dependence of the pressure generated by the pump on the flow rate of the pumped medium that changes the fluid intake regime when changing the consumption by consumers and thereby worsens the water supply conditions of consumers. Summary of the Inventions

The technical problem of the present invention consists in the development of a compact centrifugal pump capable of maintaining a pressure in a stable compressed range within a comfortable range at the changing flow rate certain and characteristic for a particular water supply system, as well as widening of the range of centrifugal pumps.

The technical result that allows solving the above problem is to reduce the slope of the pump head-capacity curve in a wide range of flow values, and the pump size and weight due to optimal scale integration in one device.

Short description of drawings

Figure 1 shows the cross section of JUMBO COMFORT centrifugal pump, Figure 2 - the left-side view of Figure 1, Figure 3 - the cross section of the centrifugal pump in axonometric projection, Fgure 4 - the head-capacity curves of two standard sizes of the pump claimed, Figure 5 - the left-side view of the built- in ejector, Figure 6 - the cross section of the built-in ejector; Figure 7 - axonometric projection of the built-in ejector.

Detailed Description of the Invention

The centrifugal pump contains the shaft-mounted impeller 6 in the housing 2, inlet chamber 11 and discharge chamber 10 of the pumped medium, as well as a jet ejector device with an inlet channel 12 for supplying the pumped medium from the inlet chamber 11 to the impeller 6, and with the inlet operating nozzle 13 installed in alignment with the above inlet channel 12 and connected to the discharge chamber 10 with its own inlet, as well as the valve made with the seat 24 and the spring-mounted and membrane 21 fixed shut-off control element 22 for regulating the flow of the pumped medium injected through the nozzle 13 of the ejector device.

The impeller 6 contains two disks between which the blades (not shown) of a special form are fixed: they are curved in the direction opposite to the direction of the impeller 6 rotation. The inlet chamber 11 is equipped with the inlet fitting 17, the discharge chamber 10 is connected to the outlet fitting 18. In the housing 2, the bypass channel 14 is made hydraulically parallel to the nozzle 13 of the ejector device. The ejector device is equipped with the tube 3 placed in the discharge chamber 10 inside which the inlet channel 12 is arranged connected to the inlet fitting 17. The valve (i.e. its shut-off control element 22) is arranged in the additional flow-type cavity 16 made in the housing 2 to control the shut-off control element 22 with the possibility of opening and closing the bypass channel 14.

The flow-type control cavity 16 is formed on one side by the above membrane 21 and connected to the discharge chamber 10 with several flow-type through holes 15 made in the housing 2, and to the inlet nozzle 13 of the ejector device - with several flow-type through holes 25. The valve seat 24 is made on the edge of the bypass channel 14 facing the control cavity 16 with the possibility of interaction with the shut-off control element 22 when the latter moves together with the membrane 21.

The tube 3 of the ejector device from the side of the nozzle 13 is made with the groove 26 connected with its bypass channel 14 in which the nozzle 14 is placed, and the inlet channel 12 is made in the form of a cone diffuser.

The shut-off control element 22 of the valve is made of brass, loaded with the compression coil spring 23 mounted in the removable cover 20 of the housing and supported through the washer (not indicated) on the membrane 21.

The shut-off control element 22 is provided with the integral brass rod (not indicated) installed in the guide 27 made integral with the removable cover 20 fixed with the screws 19.

The shut-off control element 22 of the valve is made with the spherical working surface to interact with the seat 24.

The valve seat 24 is made cone-shaped. The saddle 24 is made of brass and cast as an embedded part when casting the housing 2.

The bypass channel 14 is made composite of two bushings (not indicated), one of which is made integral (in one forging part 28) with the nozzle 13, and the other - aligned hole of the housing 2 with the valve seat 24.

The impeller 6 is equipped with the guide vane 4 enclosed in the housing 2 with the base 5 separating the fluid end of the pump from the electric motor. The ejector device on the side opposite to the nozzle 13 is made with the band 29 for mounting the guide vane 4 on it.

The fluid end is full plastic, made of polypropylene which is a thermoplastic polymer of propylene (propene). Polypropylene is obtained by polymerizing propylene in the presence of metal complex catalysts,

The tube 3 and the ejector device part 28 are connected by ultrasonic welding for which purpose the part 28 has a protrusion (see Fig. 6) of the annular shape (not indicated) along the perimeter of the joint with the tube 3; the protrusion is interfused in the annular groove (not indicated) of the part (tube) 3 when exposed to high frequency ultrasonic vibrations by the special-purpose equipment. In particular, this ensures the compactness of the device as a whole and its minimum weight compared with products of the same designation.

The centrifugal pump is completed with the automatic control unit 7 connected to the discharge chamber 10; the unit is attached to the pump housing 2 with the use of the connecting fitting 9 and fixed with the coupling nut 8, while the angle of the outlet fitting 18 relative to the pump axis (and the inlet fitting 17) can be arbitrary that provides additional convenience during installation. The connecting fitting 9 is connected to the high pressure chamber 10 of the pump.

The centrifugal pump has the electric motor 1 mounted in alignment with the impeller 6.

Preferred embodiment

The centrifugal pump operates as follows.

Before starting up the inlet and discharge chambers, the housings are completely filled with water.

When turning on the electric motor 1, the fluid pressure and motion arise as a result of the centrifugal force generated by the rotation of the impeller 6.

Passing into the channel 12 through the nozzle 13 with the tapered diameter, the liquid medium flow significantly accelerates that contributes to forming vacuum - decreased pressure area in the channel 12 of the pump suction side.

Due to the dilution effect in the jet flowing from the nozzle 13, the liquid medium from the chamber 11 is directly sucked into the channel 12. While the impeller 6 blades are rotating in the water-filled housing 2, the centrifugal force generated by them pushes the liquid from the center to the periphery where an increased pressure occurs displacing water through the discharge chamber 10 into the outlet pressure fitting 18.

In the central area of the impeller 6, the pressure decreases, and water flows there from the source - reservoir, well, hole, etc. through the inlet fitting 17, the chamber 11, and the channel 12. As a result, the fluid is supplied without interruption.

The automatic control unit 7 is an independent device and, when working with the proposed pump, it is designed for connecting the pump to the power supply when consuming water and disconnecting when not consuming; it prevents the pump from turning on when there is no water. The pump shutdown is determined by reducing the consumed output to the minimum value with a delay of 7-15 seconds. Subsequent starts up of the pump are performed by the unit 7 when the starting pressure is reached, after opening the tap.

The claimed automatically operated pump under the name JUMBO COMFORT with the built-in control valve allows to maintain the pressure value within a comfortable range at the changing flow rate certain and characteristic for a particular water supply system.

Pressure adjustment (maintaining the optimal head-capacity curve) of the pump within a comfortable range allows to stabilizing the mode of fluid consumption when changing the consumption by the consumers, i.e. avoid pressure drops when simultaneously opening and closing several points of water discharge. As shown in Fig. 4, the head of two standard sizes“60/35 comfort” and “70/50 comfort” of the claimed pump JUMBO COMFORT varies in the operating flow range up to 40 1/min within not more than 10 m, as opposed to the usual pump configuration "60/35" and "70/50".

This is ensured at the expense of operation of the valve embedded in the cavity 16 which regulates the flow ratio in the bypass channel 14 and the nozzle 13 which operates as follows. The pressure developed by the pump in the chamber 10 is monitored by the membrane 21 as the cavity 16 on the one side of the membrane 21 is connected by the holes 15 in the housing 2 to the discharge (high pressure) chamber 10. On the other hand, the force of the spring 23 acts on the membrane 21. The rod of the shut-off control element 22 is rigidly attached to the membrane 21 which, under the action of the spring 23, on the one hand, and the force of the pressure acting on the membrane 21 in the cavity 16, on the other hand, changes the flow area between the spherical surface of the shut-off control element 22 and the cone surface of the seat 24 (the valve opens or closes). When opening the valve seat 24, a larger volume of water is directed from the high- pressure chamber 10 through the holes (openings) 25 to the bypass channel 14 and further by the channel 12 of the ejector tube 3 back to the impeller 6 inlet; when closing the valve seat 24, the volume of water is less. Thus, the pressure is regulated in the chamber 10.

As a result, the pump sizes and weight are reduced due to the optimal scale integration of the valve and the nozzle, while the head changes insignificantly, as the slope of the pump head-capacity curve in the most used operating range of flow values is significantly reduced.

Industrial Applications

The present invention is embodied with multipurpose equipment extensively employed by the industry.

Claims

1. The centrifugal pump containing the shaft-mounted impeller in the housing, inlet and discharge chambers of the pumped medium, as well as a jet ejector device with an inlet channel for supplying the pumped medium from the inlet chamber to the impeller, and with the inlet operating nozzle installed in alignment with the above inlet channel and connected to the discharge chamber with its own inlet, as well as the valve made with the seat and the spring- mounted and membrane-fixed shut-off control element for regulating the flow of the pumped medium injected through the nozzle of the ejector device,

characterized in that in the housing, the bypass channel is made hydraulically parallel to the nozzle of the ejector device, the ejector device is equipped with the tube placed in the discharge chamber inside which the inlet channel is arranged, and the valve is arranged in the additional flow-type cavity made in the housing to control the shut-off control element with the possibility of full or partial opening and closing of the bypass channel; whereby the flow-type control cavity is formed on one side by the above membrane and connected to the discharge chamber with several flow-type through holes made in the housing, and to the inlet nozzle of the ejector device, wherein the valve seat is made on the edge of the bypass channel facing the control cavity with the possibility of interaction with the shut-off control element when the latter moves together with the membrane.

2. The centrifugal pump according to claim 1, characterized in that the tube of the ejector device from the side of the nozzle is made with the groove connected with its bypass channel in which the nozzle is placed, and the inlet channel is made in the form of a cone diffuser.

3. The centrifugal pump according to claim 1, characterized in that the shutoff control element of the valve is loaded with the compression coil spring mounted in the removable cover of the housing.

4. The centrifugal pump according to claim 3, characterized in that the shut-off control element is provided with the rod installed in the guide made integral with the removable cover.

5. The centrifugal pump according to claim 1, characterized in that the shut- off control element of the valve is made with the spherical working surface, and the valve seat is made cone-shaped.

6. The centrifugal pump according to claim 1, characterized in that the bypass channel is made composite of two bushings, one of which is made integral in one forging part with the nozzle, connected with the tube of the ejector device by ultrasonic welding.

7. The centrifugal pump according to claim 1, characterized in that the bypass channel is made composite of two bushings, one of which is made integral with the nozzle, and the other is made removable, integral with the valve seat.

8. The centrifugal pump according to claim 1, characterized in that the impeller is equipped with the guide vane.

9. The centrifugal pump according to claim 1, characterized in that the ejector device on the side opposite to the nozzle is made with the band for mounting the guide vane on it.

10. The centrifugal pump according to claim 1, characterized in that it is completed with the automatic control unit connected to the discharge chamber and the electric motor mounted in alignment with the impeller.