Deep sea oil well unidirectional and bidirectional well flushing conversion tool

Abstract

The invention provides a deep sea oil well one or two-way well washing conversion tool which includes an upper connection joint. The lower end of the upper connection joint is connected to a hanging cover, and an elastic locking claw is placed at the outside of the hanging cover, and a sliding sleeve is connected below the elastic locking claw. A lower connection joint is connected to the lower end of the hanging cover. The hanging cover and the lower connection joint are provided with well washing conversion sleeves, and the sliding sleeve can drive the well washing conversion sleeves to synchronously move up and down through the hanging cover. A median septum with circulation holes thereon can ensure that the liquid in the operation tube can not form throttle pressure difference. The disclosure can change the flow direction of the liquid in the conversion tool, and ensure the mud cakes and gravel in the operation tube flow into the wellbore again after the well washing finishes. In addition, the conversion tool can realize the connections of oil sleeves, and can realize positive and negative well washing operation, and can further realize well control operation under high pressure in the pit.

Description

technical field [0001] The invention belongs to the field of petroleum engineering, and in particular relates to a conversion tool for single- and double-direction well flushing of deep sea oil wells, which is used for downhole operations in oil exploitation. Background technique [0002] After the deep-sea oil and gas well completion process is implemented, formation sand will enter the wellbore in the later stage of production, resulting in serious consequences such as production decline, production equipment damage, and sand-buried wellbore. method, the current cleaning method has the following problems: [0003] 1. Run in the one-way ball seat tool to wash the well in reverse circulation, but because the ball seat is a one-way structure, it is impossible to kill the well in the operation pipe when the downhole pressure is high; [0004] 2. The two-way ball valve can be lowered to realize one-way and two-way well flushing, but there is no locking mechanism, and the one-w...

AI Technical Summary

Problems solved by technology

[0003] 1. Run in the one-way ball seat tool to wash the well in reverse circulation, but because the ball seat is a one-way structure, it is impossible to kill the well in the operation pipe when the downhole pressure is high;

[0004] 2. The two-way ball valve can be lowered to realize one-way and two-way well flushing, but there is no locking mechanism, and the one-way and two-way conversion can only be realized by stretching or compressing the pipe string, and the reliability cannot be guaranteed in highly deviated wells and horizontal wells;

[0005] 3. Lower the fishing basket and wash the well in positive circulation. However, due to the large annular space, the mud cake and gravel in the wellbore are not easy to clean, and the operation time is long, so the ideal effect cannot be achieved.

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