Treatment method for casing channeling and casing leakage of oil and gas production well

Abstract

The invention discloses a treatment method for casing channeling and casing leakage of an oil and gas production well. The treatment method comprises the following steps that S1, a first plugging agent, a second plugging agent and a third plugging agent are configured correspondingly; S2, clear water is injected into a casing to measure the water absorbing index, and the using quantity of the plugging agents is predicted preliminarily according to the water absorbing capacity of a stratum; S3, a casing gate is closed, an oil well pipe string or a polished wellbore are trapped in, the first plugging agent and the second plugging agent are extruded and injected into the casing successively, and after injecting is completed, still standing is conducted for four hours; S4, the third plugging agent is injected into the casing, then the clear water is injected into the casing so as to jack the third plugging agent to the leakage point of the casing, and a reserved mortar face is located on the leakage point of the casing; S5, the well is shut down for waiting on cement setting for 72 hours; and S6, after the process of waiting on cement setting is completed, an unloading well opening adopts the pipe string to detect a mortar plugged face, and then plug drilling is conducted. According to the treatment method for casing channeling and casing leakage of the oil and gas production well,the one-time success rate for treatment of casing channeling and casing leakage caused by damage of the oil and gas production well, especially the shallow casing, reaches 90% or above, the types andthe using quantity of treatment agents are less, and the cost is reduced.

Description

technical field [0001] The invention relates to the technical field of oilfield chemistry, in particular to a method for controlling the channeling and leakage of oil and gas production well pipes. Background technique [0002] With the continuous deepening of oilfield development and production and long-term mining, the service life of some old well oil layer casings is too long, and the cementing cement has not completely sealed the oil layer casings. Corrosion causes perforation, coupled with special and complex geological conditions, the development of salt-gypsum layer, and the movement of the earth's crust, resulting in casing deformation, damage to the formation of mud, water, oil, and long-term water injection development, especially pressurized water injection, Oil and water well casing damage is very common, and the problem of well condition deterioration is becoming more and more prominent, which affects the normal production of oil and water wells, not only reduc...

AI Technical Summary

Problems solved by technology

Resin-based plugging agents are used to control pipe channeling and leakage. The curing time is not easy to adjust, the application range is limited, and the construction safety risk is relatively high; It is difficult for the plugging agent to stay, and the amount of plugging agent used in the plugging operation is large, the success rate is low, and the cost of resin plugging agent is relatively high

Images