Gas well production string leakage detection method based on gas tracer agent

Abstract

The invention relates to a gas well production string leakage detection method based on a gas tracer agent. The gas well production string leakage detection method is characterized by comprising the following steps: 1) relieving the pressure of an annulus to be in a stable state where the pressure is not changed before testing; 2) injecting the tracer agent mixed gas, and monitoring the temperature, the pressure, the flow rate and the concentration of the injected gas in real time; (3) calculating the flow time t1 of the tracer agent in the annulus, namely the part from the well mouth to the leakage position; 4) calculating the flow time t2 of the tracer agent in an oil string, namely the part from the leakage position to the well mouth; 5) calculating the depth of the leakage point of the oil string according to the detected total flow time of components of the tracer agent from the injection part to the lower part of the oil string; 6) calculating the production string leakage degree according to the leakage concentration. The gas well production string leakage detection method can be widely applied to gas well production string leakage detection.

Description

technical field [0001] The invention relates to a method for detecting gas well production string leakage based on a gas tracer, and relates to the technical field of gas well production string leakage detection. Background technique [0002] Gas well production string leakage will cause high-pressure natural gas to leak into the annulus, and the annulus is pressurized. Since the internal pressure resistance level of the casing is lower than that of the tubing, there is a major safety hazard of blowout caused by casing failure. Many high-pressure gas wells in offshore my country have shut down due to severe annular pressure. Gas well production string leakage detection can locate the location of the string leakage and detect the degree of leakage, which is of great significance to the safety assessment of well killing in the annulus zone, the formulation of a reasonable workover plan, and the improvement of the production safety level of gas wells. [0003] At present, the...

AI Technical Summary

Problems solved by technology

[0003] At present, the existing production string leakage detection method is to use downhole logging instrument detection, whether it is downhole temperature logging or flow logging, etc., it is necessary to lower the logging instrument to the bottom of the well, and then carry out the whole well detection, which is unavoidable Cause gas well shutdown, complicated operation and high cost

Images