An intelligent well completion downhole hydraulic reversing device

Abstract

An intelligent well completion downhole hydraulic reversing device, the upper end of the valve body is provided with an upper joint, the lower end is provided with a lower joint, the lower end of the upper joint in the valve body is provided with a piston and a positioning center pipe, the lower end of the piston is connected with a valve core, and the valve core is located at the positioning In the center pipe, between the positioning center pipe and the inner wall of the valve body, the main valve core positioning locking mechanism and the auxiliary valve core positioning locking mechanism are sleeved on the positioning center pipe. A valve core reset mechanism is arranged between the side wall of the valve body and the upper end surface of the lower joint. The invention adopts the positioning and locking mechanism of the main valve core and the positioning and locking mechanism of the auxiliary valve core to form a double lock structure, which improves the reliability of identifying hydraulic signals. The invention has the advantages of compact structure, simple operation, long service life and simplified ground hydraulic operation. Advantages of the program.

Description

technical field [0001] The invention belongs to the technical field of equipment for extracting oil, gas, water, dissolvable or meltable substances or mineral mud from wells, and particularly relates to an intelligent well completion downhole hydraulic reversing device. Background technique [0002] After years of development, domestic intelligent completion technology has been widely used in nearly 1,000 oil and water wells in more than 10 domestic oil fields. The hydraulic sliding sleeve reversing movement of the downhole flow control valve of the hydraulically controlled intelligent completion system to open and close the valve holes at all levels is the key core technology to realize the downhole fluid control. [0003] At present, the domestic hydraulically controlled intelligent completion systems all use the N+1 method to directly control N downhole flow control valves, that is, N downhole flow control valves require N open oil inlet hydraulic pipelines and 1 common c...

AI Technical Summary

Problems solved by technology

This kind of hydraulic decoder has the following problems: First, due to the pressure loss on the long hydraulic pipeline in the well, the actual hydraulic force of the low-pressure unlocking hydraulic force loaded on the wellhead is less than the unlocking hydraulic force after being transmitted to the downhole hydraulic decoder, causing the lock The unlocking groove on the sleeve has not moved to the center of the locking ball, and the locking ball is still stuck in the slot on the spool to lock the spool so that the unlocking fails, and the spool cannot move under high-pressure hydraulic force; when the wellhead is loaded The hydraulic force is greater than the unlocking hydraulic force. After being transmitted to the downhole hydraulic decoder through the downhole long hydraulic pipeline, the actual hydraulic force is greater than the unlocking hydraulic force, so that the unlocking groove on the lock sleeve moves beyond the center position of the locking ball, and the locking ball remains Locking the spool in the card slot stuck on the spool makes the unlocking invalid. The spool cannot move under the high-pressure hydraulic force. It is very likely that the unlocking failure is caused by the hydraulic operation error on the ground. Therefore, the single lock sleeve structure requires accurate loading at the wellhead The low-pressure unlocking hydraulic value can ensure that the unlocking groove on the lock sleeve moves to the center of the locking ball, and the hydraulic operation on the ground is more difficult. Secondly, due to the unlocking hydraulic channel of the lock sleeve and the opening or closing hydraulic force of the flow control valve The passages are connected, and the opening or closing hydraulic force of the flow control valve is much greater than the unlocking hydraulic force of the lock sleeve. The lock sleeve has no positioning structure and cannot effectively protect the lock sleeve spring. The lock sleeve moves directly under the opening or closing hydraulic force of the flow control valve. Compress the spring of the lock sleeve to the bottom. After repeated compression, the spring of the lock sleeve is over-fatigued and prone to elastic failure. As a result, the lock sleeve cannot be reset to the initial position, causing the valve core to fail to lock, and the downhole hydraulic decoder loses the function of identifying the hydraulic signal. Three, in the process of identifying the hydraulic signal, the lock sleeve spring needs to undergo two-stage compression repeatedly. During the long-term underground work, the lock sleeve spring is extremely easy to fatigue and fail to cause the valve core to lock and fail. Fourth, use another hydraulic pipeline to suppress the pressure. The way to assist the lock sleeve to reset the initial position increases the surface hydraulic operation procedure, and these problems reduce the reliability of the overall work of the downhole hydraulic decoder

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