Method for implementing branch well window seal by using metal expansion tube

Abstract

The invention relates to a method for realizing window sealing of a multilateral well by utilization of a metallic expansion tube, which is used for completion window sealing of an oil gas well. The method is mainly realized through a window sealing structure of the multilateral well, a positioning and orienting feeding device and a running system of a branched metallic expansion tube. The method comprises the following steps: firstly, drilling of a main wellbore is completed by the drilling method of the multilateral well, and a main wellbore pipe column is run into the ground; and secondly, a whipstock is run into a designed windowing position, drilling of a branched wellbore is completed through side tracking windowing, a completion pipe column of the branched wellbore is hung on the upper part of a hollow wedge deflection tool through a pre-opening suspension device, a predeformed branched sealer is run into the window position by utilization of the feeding device, and shape recovery and inflatable seal of the hermetical metallic expansion tube are realized through the feeding system of the branched metallic expansion tube. The method solves the problems in the prior art of poor cementing quality on a joint of the multilateral well due to large difficulty of branched completion and particularly the problem of sealing of a windowing position of the multilateral well. The method can be widely used in completion window sealing operation of the multilateral well of the oil gas well.

Description

Technical field: [0001] The invention relates to a method for sealing the windows of oil, gas and water wells, which uses metal expansion tubes to seal windows of branch wells. Background technique: [0002] At present, the multilateral well technology at home and abroad is becoming more and more mature, but the drilling and completion methods below the fourth level are mainly used. The method commonly used in the existing branch well drilling method is to first use the whipstock to open a window on the casing wall to sidetrack, and after the branch hole is drilled, run the branch well completion string, and use the pre-drilling The casing realizes the penetration and mechanical support of the branch wellbore and the main wellbore at the branch well window. However, due to the difficulty in completion of branch wells, the quality of cementing at the joints of branch wells is poor, especially there is no reliable solution to the sealing problem at the window openings of bran...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a method for sealing the windows of branch wells with metal expansion tubes, which solves the problems in the prior art that the completion of branch wells is difficult and the quality of cementing at the joints of branch wells is poor, especially Sealing Problems at Window of Branch Wells

Images