SU1710929A1 - Method of automated location of defective section in piping systems - Google Patents

Abstract

Invention m. Used for automated detection of the damaged area in dead-end pipelines in all engineering networks of the city economy. The circuit of the invention is to increase the reliability, efficiency and accuracy of determining the moment and place of damage while reducing the number of monitored nodes. Pressure sensors are installed at monitored sites. The sequence and discreteness of the polling of the sites are determined and the damaged area is determined by the magnitude of the pressure change. The sensors are installed in the nodes that are most sensitive to leakage, for which, prior to operative detection of damage, the hydraulic network is analyzed using a computer by constructing a matrix using a predetermined formula. On the basis of a survey of sensors and statistical analysis of a series of consecutive pressure measurements at each monitored node, a group of sections is selected, for which the largest number of nodes that are most sensitive to leakage for the tested section coincides with nodes, in which pressure. From this group, the area with the highest likelihood of the site considered to be damaged is selected. 1 il. WITH "%

Description

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This invention relates to a technique for detecting damage to pipelines and can be used in all engineering networks of an urban community.

A known method for determining leaks in pipeline networks is based on capturing the leading edge (impulse) of the pressure drop wave. At known wave propagation speeds, lengths of sections and differences in the time of arrival of the leading front of the wave to the control points, determine the place of damage.

This method is expensive and complicated. Its application places high demands on technical support, since it requires high-speed non-switched communication channels. The method is also distinguished by low noise immunity, which complicates its practical implementation (1),

Of the known methods for detecting damaged sections of pipelines, the closest in technical essence is a method based on detecting a decrease in pressure, where, in order to determine the damaged section, a sequence of interrogation of pressure sensors and allowable rates of pressure decrease are determined, pressure is measured at monitored sites, its changes between measurements, compare it with the allowable one and determine the damaged area by exceeding the latter.

The disadvantage of this method is the high cost, the difficulty of technical implementation and the low efficiency 1 of determining the damaged area.

In order to detect damaged areas, it is required that each network node (the point of flow merging and separation) is controllable, i.e. It was equipped with a pressure sensor and telemechanics equipment, which requires a large distance of communication channels.

The difficulty of the technical implementation of this method in practice is due to the need to install telemetry equipment in underground chambers and manholes due to the predominantly underground installation of utilities.

The aim of the invention is to increase the reliability, efficiency and accuracy of determining the moment and place of damage while reducing the number of monitored nodes.

The goal is achieved by the method of automated detection of a damaged section in pipeline systems, which includes installing pressure sensors at monitored units, setting the sequence and discreteness of polling them, and determining the damaged area according to the magnitude of the pressure change. leakage sensitivity, for which, before operative detection of damages, a hydraulic network is analyzed using a computer to compare h node performance

by constructing a sensitivity matrix using the formula:

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where Stj - elements of the sensitivity matrix;

Oki. GJI - estimated costs for the section, between nodes K and i. J and 1;

Рк, PI, PJ - design pressure in nodes

K, I, j;

then nodes are selected that are most sensitive to leakage in this area according to:

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where OK, okni is the mean square measurement error at K and Kt nodes, and then based on a survey of sensors and a statistical analysis of a series of consecutive pressure measurements at each monitored node, a group of sections for which the largest number of monitored nodes with the highest leakage sensitivity for of the tested area coincides with the nodes in which the pressure has changed, and from this group choose the area with the highest probability of assessing the area considered damaged.

The formula provides for the calculation of matrix elements for three cases: a) non-adjacent nodes; b) adjacent nodes; c) matching nodes.

When analyzing the patent and scientific and technical literature, no technical solutions were found, in which there are signs similar to the set of distinctive features of the claimed technical solution.

Therefore, the proposed technical solution has the criterion of significant differences.

The drawing shows a device that implements the proposed method.

The device comprises pressure sensors 1, a computing device 2, a pressure to electric signal converter 3, an information transmission unit 4, a communication channel 5, an information receiving unit 6, a matching device 7, a printing device 8 and information display systems 9.

The method is carried out as follows.

With an interval of 1-5 minutes, the computing device 2 through the device 7 of the agreement, the information receiving unit 6 and the pressure transducer 3 interrogate the pressure sensors 1.

For each monitored node, a series of consecutive measurements of pressure is stored. After the next value is obtained, static characteristics (average, variance, etc.) are calculated for the first and second half of this series of measurements.

If the average value calculated from the second half of the measurement range is statistically significantly different from the middle first half, and other characteristics are statistically stable, the fact of a sudden change in pressure in this node is recognized.

After localization of the damaged area, the computing device 2 again starts regular polling of the pressure sensors 1. The detection algorithm to damage localization functions continuously.

The selection of control points for the protection of the pipeline system is made on the basis of the technical feasibility and sensitivity matrix analysis. The total number of sensors is determined by a feasibility study and can be significantly less than the total number of network nodes.

After that, the transition to operational damage detection.

According to the conducted technical and economic calculations, the annual economic effect from the introduction of the proposed method for an area with an installed source capacity of 250 Gcal / h exceeds 185.0 thousand rubles.

Claims (1)

The invention method of automated detection of a damaged area in pipeline systems, including the installation pressure sensors in monitored nodes, setting the sequence and discreteness of their interrogation and determining the damaged area according to the magnitude of the pressure change, characterized in that, in order to increase the reliability, efficiency and accuracy of determining the moment and location of damage while reducing the number of monitored nodes, the sensors are installed in nodes that are most sensitive to leakage, for which, prior to operative damage detection, a hydraulic network is analyzed using a computer to compare the sensitivity of the nodes by constructing a sensitivity matrix using the formula: 20 Sr, -one. where Sij is the element of the sensitivity matrix: Oy, GJI - estimated costs at the site:, Pk, PI, PJ - design pressures at the nodes, then select the nodes that are most sensitive to leakage at the site according to j Syx SyKmj Ok CTKm Where SyK, SyKm is the element of the sensitivity matrix of the control node Km to the site y: OK, 0km is the root mean square measurement error at K and Km nodes, and then, based on a survey of sensors and statistical analysis of a series of consecutive pressure measurements at each monitored node, a group of areas for which the largest number of monitored nodes with the highest leakage sensitivity for the tested section coincides with the nodes in which the pressure has changed, and from This group chooses a site with the highest probability of estimating the area considered damaged.