SU1303862A1 - Device for checking pressure - Google Patents

Abstract

This invention relates to a measurement technique. The purpose of the invention is to increase the accuracy and reliability of the device, which contains the source 1 of the auxiliary liquid pressure and the channel 2, where irregularly installed in the IV throttle 3, and the liquid through the channel 2 and the nozzles 4 is fed to the controlled point corresponding to the installation location of the nozzle 4; - flow sensors 5 and pressure 6, multiplier 7, subtractor 8, setting devices 9, 10 and indicator 11. Introducing new elements and forming new connections between the elements of the device allows to measure the parameters of flow and pressure in the hydraulic channel, and ATEM indirectly determining the pressure value in a controlled point. The increase in reliability is achieved due to the possibility of controlling the pressure in environments characterized by significant vibrations, vibrations, high temperature, because pressure and flow sensors can be sufficiently remote from the monitored point. In the second version of the device, an adjustable hydraulic resistance is introduced, allowing to establish different flow rates of the working fluid. 1 h, para. f-ly, 2 ill. (L and EjO Oh from 00 05

Description

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The invention relates to pressure control and can be used to indirectly control pressure in environments characterized by significant vibrations, oscillations, siltation or high temperature, for example, in different parts of the coal or turbo compressor station.

The aim of the invention is to increase accuracy and reliability. .

FIG. 1 shows a functional diagram of the proposed device according to the first claim; figure 2 - the same for the second.

The device according to the first embodiment (Fig. 1) contains a source of auxiliary liquid pressure 1 and a channel 2, on which an uncontrolled choke 3 is installed. Liquid is fed through channel 2 and nozzles 4 to a controlled point corresponding to the installation location of nozzle 4. On the channel in front of the choke 3 Flow sensors 5 and pressure 6 are installed. In addition, the device contains a multiplier 7, a subtractor 8, setting controls 9, 10, and an indicator 11, the output of the flow sensor being connected to the first and second inputs of the multiplier, the third input of which is connected to the output of the first adatchika and vrsod - the first input of the second subtractor whose input is connected to the output of the second set point, the third input with the pressure sensor output and output with the indicator.

The device according to the second variant (FIG. 2) contains an adjustable throttle 12 and a differential pressure gauge 13, the inputs of which are connected to the input and output of the adjustable throttle and the output connected to the fourth input of the subtractor.

The principle of operation of the device is to measure the parameters of flow and pressure in the hydraulic channel, and then to indirectly determine the value of pressure P at a controlled point. The hydraulic channel includes channel 2, throttle 3 and nozzles 4 At the entrance of the hydraulic channel pressure (ratio of P (the upper index indicates

by physical quantity; - the measured value of P will characterize

wed

electrical equivalent of P). Under the action of the pressure difference in the channel

ten

038622

a T) the flow rate of the auxiliary fluid is established, the larger, the larger the difference. Then, by the magnitude of P and the measured 5 value of the flow rate, it is possible to indirectly judge PJ,.

The value of the channel hydraulic resistance can be determined either experimentally or by calculation. The measured flow rate a allows determination of the channel loss:

   (1) 15 where p is the density of the working fluid;

g - free fall acceleration. The pressure value at the controlled point can be determined from

20 RK RO - Drel ± P-, (2) where h is the level of exceedance (prien.

marrying) pressure points P Fo

and RK, in order to reduce (or stabilize) the flow rate Q, the hydraulic channel according to the second variant contains adjustable (manual or automatic) hydraulic resistance 12. The pressure drop on the PDA on it depends

30 both on the magnitude of the flow rate and on the magnitude of its resistance. In this case, control of P is possible if

measure iPg.

35

RK P „- LRy - lRl ± R g- hr, (3)

where 1Rd p-a is the constant hydraulic resistance of line 3 and nozzle 4.

The device in the first embodiment works as follows.

The value of Q from the sensor 5 is fed to the input of the multiplier 7, which forms the value of dRd, according to the formula (1). For this setting device 9 generates a value

45 SZD p- g. The value of P from sensor 6 is fed to subtractor 8, which forms the value of P, according to the formula (2). Unit 10 forms the value of p, g, h, the value of P is reflected by the indicator 11,

50 The device according to the second variant works in the same way, with the only difference that the subtractor 8 generates the value P. According to the formula (3), and the value of the LRD is formed by a differential meter 13. All blocks and elements of the proposed device can be implemented on well-known manufactured tools. For example, a valve with a stem lock can be used as a hydraulic resistance. A manual gate valve or automatic flow controller can be used as the adjustable resistance 12. B as a flow sensor can be used, for example, inductive or ultrasonic, and as sensors 6 pressure and differential pressure gauge - direct measurement sensors

Expansion of the field of application of the proposed device is achieved due to the possibility of controlling the pressure at various points of the coal sump of the hydraulic mine station and other objects, the technology of which is not disturbed by the additional introduction of the working flow rate

fluid. Increase reliability up to -20 with the output of the flow sensor connected

This is due to the possibility of controlling pressures in environments characterized by significant vibrations, oscillations, silting, or high temperatures, since the pressure and flow sensors can be quite remote from the point to be monitored.

In addition, an increase in the field of application and reliability of the device according to the second variant is achieved by introducing adjustable hydraulic resistance, which makes it possible to establish different flow rates of the working fluid depending on changing conditions at the controlled point.

which prevents the process from being affected by the working fluid.

Claims (2)

1. A device for monitoring pressure, containing an indicator, a channel, an input connected to a pressure source of an auxiliary medium: and an output communicated with the measured medium, a throttle installed in the channel, a flow sensor and a pressure sensor, characterized in that, in order to improve accuracy, it is equipped with a multiplier with two inputs, a subtracting unit with four inputs and the first and second sensors of hydraulic loss coefficients and increase in the height of the channel input installation below its output. with the first input of the multiplier, the second input of which is connected to the output of the first setter, and the output, to the first input of the subtracting unit, the second input which is connected to the output of the second unit, the third input is connected to the output of the pressure sensor, and the output is connected to the indicator. 2. The device according to claim 1, of which is, in order to increase reliability, it is equipped with a differential manometer, connected by inputs to the input and output of the throttle, and output to the fourth input subtraction unit. Editor E. Sligan Order 1298/41. Circulation 777 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 Compiled by .A.Sokolovsky Tehred A. Kravchuk Proofreader A.Zimokosov