Seal-examining testing method

Abstract

The invention discloses a seal-examining testing method. The method comprises the steps that a seal-examining tester is lowered into a water distributor working barrel located in a casing pipe; wateris continuously injected into an oil pipe at a constant pressure, wherein the duration of continuous water injection is not less than 24 hours; and the first pressure and the second pressure are continuously detected in the water injection period. If sealing of a packer to be detected fails, the injected water can directly enter an upper annular space through the packer to be detected, so that thesecond pressure is basically the same as the first pressure in the water injection period, and the difference value between the first pressure and the second pressure does not exceed the preset threshold value all the time; and if tight sealing of the packer to be detected is achieved, the injected water cannot enter the upper annular space through the packer to be detected, when water injectionis started, the pressure in the stratum is relatively large, the difference value between the first pressure and the second pressure is relatively small, along with water injection, the stratum continuously absorbs the water, then the stratum pressure is gradually reduced, the second pressure is gradually reduced, and the difference value between the first pressure and the second pressure gradually exceeds the preset threshold value.

Description

technical field [0001] The invention relates to the field of oil and gas exploitation, in particular to a sealing test method. Background technique [0002] In oil production engineering, packers can be used to stratify formations. An annular space is formed between the casing and the tubing in the water well, and a packer is arranged between the casing and the tubing, and the tightly sealed packer can isolate the annular space. [0003] In order to ensure normal production, it is usually necessary to conduct a seal test, that is, to detect the tightness of the packer. At present, during the seal test, the seal tester will be lowered into the water distributor mandrel located in the casing. The seal tester has two pressure sensors, one of which can detect the casing protection packer (referred to as the most The pressure of the annular space between the packer near the wellhead) and the packer to be tested, and another pressure sensor can detect the pressure of the annular...

AI Technical Summary

Problems solved by technology

[0004] For some water wells, the long-term water injection in the production process leads to higher and higher formation pressure, and the formation water absorption effect is getting worse and worse. The pressure of the space is basically kept constant, making it difficult to judge the tightness of the packer to be tested

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