SU1051486A2 - Probe for measuring space charge in dielectric liquid - Google Patents

Abstract

PROBE OF VOLUME ELECTRIC CHARGE IN DIELECTRIC FLUID at author. St. No. 879514, I distinguish 14 Ices by the fact that in order to increase the accuracy of measurements, the three-way valve body is electrically connected to the case of the receiving tank and isolated from the main line of the test liquid.

Description

The invention relates to measuring technique, in particular to measuring the space charge in dielectric liquids, and can be used for periodic monitoring of the space charge of liquids, as well as for calibrating sensors for continuous monitoring of this charge in the chemical, oil industry and other sectors of the national economy. ; To control the safety of technological operations with dielectric liquids from the point of view of the possible accumulation of electric charge, it is necessary to control the volume charge in liquids flowing through pipelines.

According to the main author. St. No. 879514, a volumetric electric charge probe in a dielectric fluid is known, consisting of a receiving reservoir that is electrically insulated from the earth, placed in a shielded housing and connected to a potential meter, in which the receiving reservoir is made in the form of a cylindrical vessel, inside which a piston is installed, the vessel being connected to the main the test fluid through the introduced three-way valve {1).

However, this probe is characterized by insufficient measurement accuracy due to the fact that during its operation additional electrification of the liquid in the tap occurs.

The purpose of the invention is to improve the accuracy of measurements. 35

This goal is achieved by the fact that in the probe of the volumetric electric charge in the dielectric fluid, the body of the three-way valve is electrically connected to the housing of the receiving reservoir and isolated from the line of the liquid under investigation.

, The drawing shows a structural diagram of the proposed probe.

The probe consists of a receiving rod, a tank 1, made in the form of a metal vessel electrically insulated from the ground, a screen 2, electrically connected to the ground and one of the inputs of the potential meter 3, the other input of which is connected to the receiving tank, and a three-way valve 4, through which the receiving tank is connected to the pipeline 5. The three-way valve is electrically connected to the receiving 55 of the tank * and connected to the flange 6 of the pipeline through an insulating spacer 7. Crane controls, max the eggs, as well as the drain pipe 8, are brought out through the screen using electrical insulating spacers 9. The screen covers both the tank and the tap.

Inside the tank is placed a piston 10 with a rod 11 made of insulating material. The rod passes through the hole in the bottom of the tank and the screen and is equipped with a trigger device 12. The vessel of the receiving tank with a piston and rod is a sample dispenser,

The probe works as follows.

In the initial position, the valve 4 blocks the access of fluid to the tank 1 and the side outlet. The piston 10 is in its highest position and is held by the trigger device 12. When the test fluid flows through the pipe ·, wire 5 creates hydrostatic pressure in it. After the valve 4 is moved to the sampling position 2θ, in which the pipe is connected to the receiving tank, the same pressure is created above the piston as in the pipe. Using the trigger device 12, the piston rod 11 is released. Liquid, moving the piston 10 to the bottom, fills the reservoir 1. The charge introduced into the reservoir 1 together with the liquid creates a potential, which is measured by the meter 3 after filling the reservoir 1. When the fluid flows in the valve 4, the liquid acquires additional charge, which is also introduced into the tank 1. The acquisition of a charge by the liquid in the tap occurs due to the separation of the double layer on the walls of the passage opening of the tap. In this case, charges of one sign are carried away by the liquid and enter the reservoir 1, and charges of another sign of the same magnitude remain on the tap. Due to the fact that the tap 4 is electrically connected to the tank 1, the total charge of the tap-tank system remains unchanged regardless of the degree of electrification of the liquid in the tap and the measured potential is created only by the charge introduced by the liquid from the pipeline main. Electrical insulating spacers 9 protect against leakage of this charge when handling the crane.

As laboratory studies show, the charges acquired by the liquid in the valve during one sampling can reach 0.01 μC, which corresponds to a space charge density of ^ 20 μC / m;

This amounts to an additional reduced measurement error of up to 20% at. slag 100 µC / m? Therefore, the proposed probe in comparison with the known reduces the additional error by 3-4 times.

ВНИИПИ Order 8661/46 Circulation 511 Subscription

Branch of PPP ^ Patent *, Uzhgorod, Project 4,

Claims (1)

VOLUME OF A VOLUME ELECTRIC CHARGE IN A DIELECTRIC LIQUID by author. St. No. 879514, characterized in that, in order to improve the accuracy of measurements, the body of the three-way valve is electrically connected to the body of the receiving tank and is isolated from the line of the test fluid.