CN1609458A

CN1609458A - Double-priming centrifugal pump

Info

Publication number: CN1609458A
Application number: CN 200310118915
Authority: CN
Inventors: 李文广
Original assignee: Lanzhou University of Technology
Current assignee: Lanzhou University of Technology
Priority date: 2003-10-23
Filing date: 2003-10-23
Publication date: 2005-04-27

Abstract

The present invention is one kind of double attraction centrifugal pump and aims at lowering the cavitation erosion allowance of the main vane wheel, raising the cavitation erosion specific rotation speed, lowering the installation height of pump and reducing pump volume. The double attraction centrifugal pump consists of rotation shaft, pump body, pump cover, and double attraction vane wheel comprising two back-to-back installed vane wheels. There are two inducing vane wheels installed on the rotation shaft on two sides os the double attraction vane wheel and symmetrical about the geometrical central line of the extrudation chamber.

Description

A kind of double-suction centrifugal pump

Technical field

The present invention relates to the centrifugal pump in the fluid machinery, it is a kind of low net positive suction head, the double suction pump of low solid-liquid two-phase flow sand erosion, except being suitable for the various applications of original double suction pump, also be specially adapted to the net positive suction head requirement is harsh and solid-liquid two-phase flow will have cavitation and the symphyogenetic wearing and tearing occasion of silt.

Background technique

Double-suction centrifugal pump is that the impeller with two same structures is fitted together parallel operation back-to-back.The Yellow River water system is irrigated by lifting water to a higher level with a water pump, etc. pump and has been adopted double suction pump in a large number, owing to contain high concentration silt in the river, water pump is under the synergy of cavitation and silt, water pump vane has suffered heavy wear, and pump efficiency descends, and power consumption increases, the water lift amount descends, the open channel sedimentation, and economic loss is huge.

The objective of the invention is to reduce the main impeller net positive suction head, improve cavitation specific speed, reduce the setting height(from bottom) of pump, reduce the volume of pump.

Summary of the invention

The present invention is a kind of double-suction centrifugal pump, comprise rotating shaft (8), the pump housing (1), pump cover (6), 2 suction pipes (9) that are used to suck liquid are arranged on the pump housing (1), a discharge tube (10) that is used for drain, two semicircular cavities (5) on the pump housing (1), (5 '), two semicircular cavities (3) on the pump cover (6), (3 '), two impellers lean against privately and are installed together, constitute double-entry impeller (7), go up impeller (4), (4 ') that are separately installed with 1 inducing action in the both sides of double-entry impeller (7) in rotating shaft (8).Impeller (4), (4 ') are symmetrical in the geometric center lines (OO ') of delivery chamber.

Usefulness of the present invention is: impeller (4), (4 ') of playing inducing action are the low lift axial-flow blowers, be installed in main impeller-centrifugal impeller front, improved the fluid pressure at Centrifugal Impeller Inlet place, reduced the main impeller net positive suction head, cavitation specific speed brings up to 1500～5000, can significantly reduce the setting height(from bottom) of pump, improve rotating speed, reduce the volume of pump.

The present invention also has the following advantages:

(1) when rotating speed is constant, when cavitation specific speed brings up to 1500 by 850, net positive suction head will reduce by 50%; If former net positive suction head is sin, behind the installation inducer, net positive suction head then becomes 25m, so can reduce pump setting height(from bottom) 25m.This shows, behind the installation inducer, can significantly reduce the setting height(from bottom) of pump, reduce the earthwork evacuation amount.The Yellow River water system chopped-off head is irrigated by lifting water to a higher level with a water pump, etc. pumping plant, have more the meaning of particular importance.

1. widened original double suction pump application.The two inducer double suction pumps of the band that the present invention proposes can require to use under the harsh occasion at net positive suction head.

So that inducer blade and double-entry impeller blade along the circumferential direction stagger, inducer can be led the silt in the solid-liquid two-phase flow people's double-entry impeller runner middle part, avoid the collision of silt and double-entry impeller front side of vane, reduce the double-entry impeller wearing and tearing, improve impeller working life.

(4) silt in the water causes pump cavitation easily, after inducer is installed, improve double-entry impeller and gone into a day fluid pressure, when being moved, water pump is difficult for taking place cavitation under variable working condition, avoided the synergy of distinctive cavitation of solid-liquid two-phase flow and silt to make the water pump vane phenomenon of wearing and tearing fast, thereby improve pump working life, avoid rotor oscillation, increase the pump operation reliability.

Description of drawings

Fig. 1 is a plan view of the present invention, Fig. 2 be the B-B of Fig. 1 to cross sectional side view, Fig. 1 also is that the A-A of Fig. 2 is to sectional view.

Specific implementation

As shown in Figure 1 and Figure 2, the present invention is made up of three parts, and promptly rotor part, the pump housing (1) and pump cover (6) are formed.Rotor part mainly comprises rotating shaft (8), bearing support (2), there are 2 to be used to suck the suction pipe (9) of liquid, the discharge tube (10) that 1 is used for drain on the pump housing (1), can hold 2 half-cylindrical cavitys (5) and (5 ') of two impellers (4) that play to lure effect and (4 ').The pump housing is cast with cavity half on (1), and the outside of cavity is half of spirality delivery chamber.Half cavity can hold main impeller-double-entry impeller (7).Pump cover (6) has 2 half-cylindrical cavitys (3) and (3 ') that can hold two impellers (4) and (4 '), is cast with in addition half cavity on it, the outside of cavity be the spirality delivery chamber second half, half cavity can hold main impeller-double-entry impeller (7).Impeller (4), (4 ') are symmetrical in the geometric center lines (OO ') of delivery chamber.The pump housing (1) and pump cover (6) altogether after, form the complete half spiral shell shape suction chamber and the spirality delivery chamber that hold main impeller-double-entry impeller (7) jointly.(11) be the leg of centrifugal pump.

Rotor part by two bearing bracket (2) and (2 ') in two end supports.Rotating shaft (8) can be assembled separately.The set screw nut of opening pump cover (2) and taking the rigid bearing support apart just can access rotor part.Other annex, as: bearing support, packing seal and coupling etc. are all selected the standard piece of pump industry for use.

Claims

1, a kind of double-suction centrifugal pump, comprise rotating shaft (8), the pump housing (1), pump cover (6), 2 suction pipes (9) that are used to suck liquid are arranged on the pump housing (1), a discharge tube (10) that is used for drain, two semicircular cavities (5) on the pump housing (1), (5 '), two semicircular cavities (3) on the pump cover (6), (3 '), two impellers lean against privately and are installed together, constitute double-entry impeller (7), it is characterized in that going up impeller (4), (4 ') that are separately installed with 1 inducing action in the both sides of double-entry impeller (7) in rotating shaft (8);

2, double-suction centrifugal pump according to claim 1 is characterized in that impeller (4), (4 ') are symmetrical in the geometric center lines (OO ') of delivery chamber.