SU806987A1 - Apparatus for locating leak in pipeline - Google Patents

Description

t

The invention relates to devices for remote monitoring of the state of pipelines and is intended to detect damage in long-distance pipeline transport systems.

A device for detecting leaks in liquid pipelines, a coaxial cable with capillaries in a dielectric and an outer conductor serving as a leak detector that is connected to a pulse generator and a receiver with a secondary device, is known to be contained in the heat insulation. When the capillaries are filled with liquid in place of the pipeline leak, the impedance of the coaxial cable changes, and in this area the probe pulses reflected by the generator are reflected. The time of arrival of the reflected pulse determines the location of the leak l.

.

; The known device provides high accuracy in determining the location of a pipeline leak. However, with a rather complicated constructive performance (including the manufacture and laying of a special cable)

accuracy depends on climatic conditions.

It is also known a leak location device containing an insulated cable laid in an electrically conducting pipeline, connected at the end of a pipeline with an insulated conductor embedded in a pipe wall. At the beginning of the pipeline, the ends of the insulated cable and the insulated conductor are connected to the location recorder, those .4i, which is played by the DC measuring bridge. A galvanometer is installed in one diagonal of the measuring bridge, to the ends of which the cable and conductor ends are connected, forming the two arms of the measured resistances. The power supply of the other diagonal of the measuring bridge is permanently connected by one pole to the engine of the balancing resistor, and the other pole is connected to the grounding conductor. If damage occurs in the pipeline, the insulation of the conductor embedded in the wall is broken and it is grounded. Locks the power supply circuit of the measuring bridge. The distance to the injury is determined by

Know the lengths of the insulated cable and conductor and the measured resistance 2.

This device cannot be used in pipelines of hydro-transport systems of great plausibility, since during transportation of pulp (for example, water-coal mixture). Having abrasive properties, insulated cable / laid inside the pipeline will often fail to lead to numerous failures in the operation of the device. Therefore, the reliability of such a device will be low.

In addition, the manufacture of special pipes with an insulated conductor built into the walls and the subsequent installation of such a pipeline with a gasket inside its insulated cable significantly complicate the construction of the whole; The aim of the invention is to increase the reliability of the device and simplify its design. ; The goal is achieved by the fact that in a known device for detecting a leak in a pipeline with an electrical conductor, a tapping fluid, provided with an insulated conductor, laid along the pipeline and connected to one of the clips of the leak detector, covers the outer surface of the pipeline, the wall of which is connected to another clamp the recorder of the leak location; in this case, the conductor may be wound onto the pipeline in a spiral and placed between the layers of paper waterproofing poured on top with bitumen.

. When a pipeline ruptures, the electrically conductive liquid flowing out will close the pipeline wall and the conductor laid along its surface into the electrical circuit, and the leak detector registers the resistance of this conductor to the point of contact with the pipeline, i.e. distance to meta leaks.

H4 of the drawing shows schematically a device for detecting a leak in a pipeline, a general view.

The device comprises a pipeline 1 with an electrically conductive liquid 2, on the outer surface of which is a layer of paper waterproofing layers.

3 high-resistance (for example, constants) conductor 4. End of conductor

4 and the wall of the pipeline 1 are connected

with the clips of the recorder 5, the leak is a single-line DC measuring bridge of the leak points in the pipeline.

If pipeline 1 is damaged in place of leakage of an electrically conductive fluid (slurry) 2, conductor A and wall of pipeline 1 are closed into an electrical circuit. This electrical circuit becomes the measurement arm of the leakage recorder 5, and its resistance is measured after balancing the measuring bridge to the point of leak 6 is defined by the expression ng S

and.

e

where r

measured resistance;

high resistance conductor section;

p is the resistivity of the high-resistance conductor; k - coefficient of step of winding

wire.

In fact, the recorder .5 leakage location 6 measures the total resistance of the conductor 4 to the point of leakage b, the resistance of the steel pipe of pipeline 1 and the transitional resistance of electrically conducting fluid 2. However, when laying high-resistance constantan wire, the values of the resistance of the pipeline and the electric

common fluid in size

can

Ls practically neglected.

The use of the proposed device has a number of advantages. First of all, the use of the conductor wall of an electric circuit practically not subject to wear and the high-resistance wire wound on its outer surface greatly increases the reliability of the device and simplifies its design. In addition, the laying of the high-resistance conductor is well combined with the insulating technology of trunk pipelines developed and implemented in production, therefore the costs of laying are minimal and are determined mainly by the cost of the high-conductor.

Claims (2)

1. A device for detecting a leak in a pipeline with an electrically conducting fluid, including an insulated conductor laid along the pipeline to the connected g {. One of the clips of the leak recorder, characterized in that, in order to increase the reliability and simplify the construction, the insulated conductor covers the outer surface of the pipeline, the wall of which is connected to another clip of the leak recorder. 2. The device according to Clause 1, that is, the conductor is wound on the pipeline in a spiral and placed between the layers of paper waterproofing poured on top with bitumen. Sources of information taken into account in the examination 1. The USSR author's certificate 612102, cl. F 17 D 5/02, 1972. 2. German Patent No. 1940872, cl. F 17 D 5/06, published 1971. 3