Method and a system for detecting rod pumped well polish rod suspension center dead point

Abstract

The invention discloses a method and system for detecting a rod pumped well polish rod suspension center dead point. The detecting method comprises the steps that a rod pumped well electric work diagram X(i) in one stroke period is collected based on a synchronous indicator diagram; a time series x(i) is set based on the electric work diagram X(i), y'(i) is calculated according to a mean filteringformula, a corrected time series is obtained, and a filtered output signal y(i) is obtained based on the corrected time series; a variance Qd(i) of the time series x(i) and the filtered output signaly(i) is obtained; and the suspension center dead point is obtained based on the variance Qd(i). The method and system have the advantages that online correction of the electric work diagram and the indicator diagram of a rod pumped well can be achieved, real-time detection of the suspension center dead point is helpful for judging whether a displacement sensor of the indicator diagram is normal or not, the monitoring capability of the rod pumped well working condition is improved, and the method is high in safety and convenient in actual application installation, operation and maintenance.

Description

technical field [0001] The invention relates to the field of oil pumping well working condition monitoring and liquid volume measurement, and more particularly relates to a method and system for detecting the dead point of the polished rod of the pumping well. Background technique [0002] In order to improve the production efficiency and management level of oil and gas production enterprises, oil wells in various oil fields generally use dynamometer diagrams to measure oil well fluid volume online and monitor oil well working conditions. The dynamometer monitoring diagnostic measurement system consists of three parts: perception layer, transmission layer and application layer. Data such as pumping well indicator map and well start and stop information are collected through on-site sensor equipment, and the data is transmitted to the data processing unit RTU. The RTU transmits the data to the server through a wireless or wired network, and the server calculates and processes...

AI Technical Summary

Problems solved by technology

For the displacement detection method, the most commonly used method is to measure the position indirectly by measuring the acceleration, which can realize the wireless test of the displacement, simplify the test procedure, improve the reliability of the dynamometer measuring instrument and the accuracy of the displacement test data, However, there is a problem in the acceleration sensor measuring the displacement that the dead point drifts due to the acceleration oscillation of the dead point, which affects the displacement detection accuracy; for the dead point switch method, the dead point switch installed at the suspension point is easily damaged by collision

In summary, the current dead point detection method for the suspension point of pumping wells has problems such as high investment and maintenance costs, poor implementability, and unguaranteed accuracy.

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