Well completion sand prevention process and sand prevention strings thereof

Abstract

Disclosed are a well completion sand prevention process and sand prevention strings thereof. The process comprises the following steps of assembling an inner string and an outer ring; mounting a hydraulic rotation device; connecting a top packer and a setting tool; performing function testing; drilling down to a set position; performing completion fluid replacement, gel breaking fluid replacement, gel breaking and well flushing; performing ball feeding, setting the top packer and examining the sealing performance; pulling out a feeding drill and the inner string. The sand prevention strings comprise the outer string and the inner string, the inner string is arranged inside the cavity of the outer string and comprises an insertion seal, a positioning head and a flushing pipe, and the outer string comprises a sealing bore, a screen pipe and a blank tubing; the tops of the blank tubing and the flushing pipe are connected with the top packer, and the top packer is connected with the feeding drill through the setting tool; the outside of the outer string is also provided with the hydraulic rotation device, and the inside of the inner string is provided with a fluid path for the driving fluid of the hydraulic rotation device to pass through; the hydraulic rotation device is connected with a surface pump through the fluid path.

Description

technical field [0001] The invention relates to a well completion technology in oil exploitation, in particular to a well completion sand control technology and a sand control pipe string. Background technique [0002] In the prior art, the sand control pipe string of the well completion sand control technology relies on the self gravity of the pipe string to overcome the buoyancy and the frictional resistance in the casing and the open hole to run in. see figure 1 , figure 1 It is a schematic diagram of the structure of the sand control string in the prior art. The bottom of the sand control pipe string in the prior art is a floating shoe 10 with a round head. The outer pipe string mainly includes the floating shoe 10, the well cleaning sealing cylinder 20, the screen pipe 30, the blind pipe 40, etc., which play the role of sand control and isolation; The pipe string mainly includes insertion seal 50, positioning head 60, flushing pipe 70, etc., to establish a circulatio...

AI Technical Summary

Problems solved by technology

[0014] a) Before the sand control string is drilled to the design position, in case of complicated situations, the treatment measures are single, and can only be lifted by lifting, lowering the active string, and small displacement circulation. Since the setting tool is not allowed to withstand torque, or only Can withstand very limited torque, can't handle complex situations, and the effect is not ideal

[0015] b) The operation is risky and the one-time success rate is low. Once rework or accident occurs, the operation progress will be seriously affected and huge economic losses will be caused.

Images