RU2324075C2 - Pump - Google Patents

Abstract

FIELD: engineering industry; pumps with decreased noise and vibration level.

SUBSTANCE: Pump includes frame, main and secondary rotors with screws, drive motor, and pony motor on the main and driven shafts. The screw's projection width does not equal the width of space on each rotor. Projection width on the main rotor equals the projection width of the driven rotor.

EFFECT: decreased noise and vibration level.

1 dwg

Description

The pump is designed to operate in systems and rooms where low noise levels are required when pumping water and other high-pressure liquids behind the pump.

Known multistage centrifugal pumps on bearings with reduced levels of noise and vibration (see SU 530114 A, 09/30/1976, F04D 29/66). The disadvantage of such pumps is that in case of pumping liquid into a system with high backpressure, one has to turn on several pumps in series or use a pump of large dimensions and weight. Volumetric pumps are not applicable in such systems, as they have increased requirements for fluid purity.

A multiphase pump is known for pumping contaminated liquids (see SU 1435819 A, 11/07/1988, F04C 2/16). Pumps of this design are able to develop high pressure at low peripheral speeds of the working bodies. Unlike screw pumps, where the rotation is transferred from the leading screw to the driven one by performing a special screw profile, in multiphase pumps the working bodies are made in the form of two screws with thick blades that enter into each other. The screws must rotate at the same angular speed.

The disadvantage of these pumps is the presence of a pair of gears synchronizing the rotation of the shafts. As you know, gearing is a source of increased noise and vibration.

A patent is known from the patent literature for a pump adopted as a prototype, comprising a housing, driving and driven rotors located therein, having cuts in the form of a screw, the protrusions of one of which enter the grooves of the other, a drive motor located on the drive shaft and an auxiliary electric motor located on the driven shaft (see RU 2002116380 A, 12.27.2003, F04C 2/16).

The disadvantage of this pump is increased noise and vibration.

In addition, the fundamental difference between the claimed invention and the prototype is that the synchronization task is solved without the use of a synchronization unit, and the location of the main and additional engines can be both composite and on the one hand.

The claimed invention allows, due to the choice of the width of the protrusions, to distribute the costs and power on the shafts, additionally manipulating the width of the protrusions, and by changing the resistance in the gap between the housing and the rotor, to reduce the flow rate and thereby the noise generated by the flow, the sound power level of which depends on the degree of speed .

An object of the present invention is to provide a pump with reduced noise and vibration levels.

The above problem is solved in the pump, which contains a housing, the driving and driven rotors located in it, having cuts in the form of a screw, the protrusions of one of which enter the grooves of the other, a drive motor located on the drive shaft and an auxiliary electric motor located on the driven shaft, according to According to the invention, on each pump rotor, the width of the protrusions of the screw is not equal to the width of the cavity, and on the leading rotor, the width of the protrusion is equal to the width of the cavity on the driven rotor.

The drawing shows the design of the proposed pump.

The pump consists of a housing 1, in which the drive shaft 2 and the driven shaft 3 are located. The main motor 4 is located on the drive shaft 2, and the auxiliary motor 5 is located on the driven shaft 3. The shafts are sealed by mechanical seals 6. On the drive shaft there is a screw 7 with wide cavities 8, on the driven one, a screw 9 with narrow cavities 10, which includes the protrusions (blades) 11 of the screw 7. The shafts with the parts located on them form the driving and driven rotors of the pump. On each pump rotor, the width of the protrusions (blades) of the screw is not equal to the width of the troughs, and the protrusions (blades) of the screw freely (with a gap) enter the grooves of the screw on the other rotor. Cutting augers with wide and narrow troughs allows you to redistribute power between the shafts and use an auxiliary electric motor of small power. To unload the pump rotors from axial forces, the pump is made two-flow, and the working bodies - screws on each rotor have right and left cuts.

The residual axial forces on the rotors are perceived by the thrust bearings 12. The pump can be located vertically, as shown in the drawing, or horizontally. Flanges can be arranged “in line”.

The pump operates as follows.

The fluid through the suction flange 13 enters the pump inlet, then the flow bifurcates and enters the inlet of the working bodies. Flows from working bodies are directed to a common discharge chamber 14 and then to discharge flange 15. When powered from one network and one starting device, asynchronous motors rotating in one direction are synchronized in revolutions, and the execution of rotors on sliding bearings eliminates the vibration inherent in ball bearings. This design of the pump allows you to have minimal levels of noise and vibration while ensuring the specified energy characteristics.

Claims (1)

A pump containing a housing, leading and driven rotors located therein, having screw cuts, the protrusions of one of which enter the grooves of the other, a drive motor located on the drive shaft and an auxiliary electric motor located on the driven shaft, characterized in that on each pump rotor the width of the protrusions of the screw is not equal to the width of the cavity, and on the leading rotor, the width of the protrusion is equal to the width of the cavity on the driven rotor.