RU1800121C - Method for feed control of pump plant with rigid blade pumps - Google Patents

Abstract

SUMMARY OF THE INVENTION: the hydraulic resistance of pressure pipes, pipelines is changed by transferring part of the liquid from one pipe line to another through an adjustable throttle device. The pressure drop across the device is set in accordance with a predetermined relationship. 1 ill.

Description

The invention relates to controlling the flow of pumping stations and can be used in the presence of two or more pressure pipelines.

The purpose of the invention is to increase the accuracy of regulation, increase the reliability of the pumping station and reduce energy consumption. When using the invention, the range of stepless flow control is increased, and the magnitude of the increase in pressure during water hammer decreases.

The drawing shows a diagram of the main equipment of the pumping station.

The proposed method is designed to control the flow of a pumping station, consisting of centrifugal pump units 1 with fixed-vane impellers operating in parallel. The individual threads of the pressure pipelines 2 of the pump units 1 are connected into two (or more) common pressure pipelines 3 and 3, and each of the working pumps is equipped with a butterfly valve 4.

The feed control method is carried out as follows.

Common pressure pipelines 3 and 3 are interconnected by a bypass pipe 5, which is equipped with a throttle device 6. The difference in pressure at the inlet and. the outlet of water from the throttle device is measured by a differential pressure gauge 7.

The number of pump units 1 required to provide a given flow rate is determined. The flow of these pumping units 1 when they work together and the open throttle device 6 on the bypass pipe 5 should be greater than the set flow rate, but less than the set flow rate when these pumps operate only to their individual pressure pipe 2 (with the throttle device 6 closed). Feed control is carried out by changing the hydraulic resistance of the throttle device, i.e. a change in the degree of its discovery.

Start up the pumping units 1. which should provide a given

ate

WITH

CD O O

d

Yu

feed with the open throttle device 6 on the bypass pipe 5. The feed of the pumping station will be greater than the specified one. The throttle device 6 is covered to reduce the feed. The feed is reduced. The magnitude of the change in supply is judged by the readings of the differential pressure gauge 7 by measuring the pressure difference in the common pressure pipelines 3 and 3 at the point of their connection by the bypass pipe 5.

The pressure drop across the throttle device is set in accordance with the dependence

Yes2

BEFORE

 (NZ - But)

Max

where Ne is the pressure drop across the throttle device when it is completely closed;

But - the pressure drop across the throttle device when it is fully open;

A O is a predetermined amount of change in the pumping station flow;

And Omax is the change in the supply of the pumping station when the throttle device is moved from the fully open position to the fully closed position.

Claims (1)

The claims A method of controlling the flow of a pump station with rigid vane pumps. 0 5 connected in parallel by groups to several common threads of pressure pipelines by changing the hydraulic resistance of the latter, characterized in that, in order to increase the accuracy of regulation, increase the reliability of the station and reduce energy consumption / hydraulic resistance, the bypass of a part of the liquid is changed. from one thread of the pressure pipe to another through an adjustable throttle device, and the pressure drop across the throttle device is set in accordance with the dependence N NZAO2 AO2 Max where H3 is the pressure drop across the throttle device when it is completely closed; H0 is the pressure drop across the throttle device when it is fully open; A Q is a predetermined rate of change in the pumping station flow; And in Oman, a change in the pumping station flow when the throttle device is moved from the fully open position to the fully closed position.