Treatment method of cement sheath outside the screen after cement injection

Abstract

The invention discloses a method of processing a cement sheath outside a screen pipe after cementing well completion. The method includes crushing the cement sheath outside the screen pipe without perforating to greatly reducing production cost. The method is particularly suitable for horizontal wells. The method includes closing a sleeve pipe valve and a blowout preventer on a wellhead after a cement sheath extrusion pickling string outside the screen pipe is tripped to the design position of the screen pipe, utilizing a cement sheath expulsion device of the cement sheath expulsion pickling string outside the screen pipe to seal a annulus between an oil tube and the screen pipe, expulsing and crushing the cement sheath outside the screen pipe outside the cement sheath expulsion device from the front of the oil tube to finish lower probing segment by segment to an artificial bottom of a well, utilizing the cement sheath expulsion pickling string outside the screen pipe to open a well washing valve at the artificial bottom of the well to build a reverse circulation well washing tunnel, pickling a near wellbore formation with flushing fluid, and conveying disintegrating slag and dirt of the cement sheath outside the screen pipe out of the well to the ground. The processing method is capable of reaching purposes that the next string can finish crushing cement sheath outside screen pipes and utilize pickling solution to wash a well, so that production and construction cost can be greatly reduced.

Description

technical field [0001] The invention relates to a cementing well completion method in the field of oil exploitation, in particular to a method for treating the cement sheath outside the screen pipe after cementing well completion, which can squeeze and break the cement sheath outside the screen pipe without perforating, greatly reducing production cost, especially for horizontal wells. Background technique [0002] With the continuous maturity of horizontal well technology, the scale of application has also expanded rapidly, and it has become an important means for the adjustment and tapping of potentials in old oilfield areas to improve oil recovery and the efficient development of production capacity in new areas. During the completion of cement injection at the top of the horizontal well screen, due to tool reasons or special downhole conditions, the screen section will leak into the cement slurry and the oil layer will be solidified. The existing technical solution is t...

AI Technical Summary

Problems solved by technology

The shortcoming that existing technical scheme exists is: During the process of drilling the cement plug, the drill bit is likely to cause eccentric wear on the base pipe of the screen pipe, which affects the strength of the screen pipe; After the small filter sand pipe is suspended in the screen pipe, the inner diameter becomes smaller, and the size of the running tool is limited in the later operation, which brings inconvenience to the construction; The treatment cycle is long, and the cost of well completion after secondary sand control in the pipe is greatly increased

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