Bit pressure controlled type downhole circulating pup joint and continuous pipe drilling plug dynamic flushing process

Abstract

The invention discloses a bit pressure controlled type downhole circulating pup joint and a continuous pipe drilling plug dynamic flushing process. The circulating pup joint comprises an upper joint body and a lower joint body which are in sliding fit through an elastic element. Flow passing holes are formed in the lower end of the side wall of the upper joint body. A front spraying passageway anda side spraying passageway are arranged between the lower joint body and the upper joint body, and the lower joint body can slide in the axial direction of the upper joint body, so that one of the flow passing holes communicates with the front spraying passageway or the side spraying passageway. Side spraying holes are formed in the side wall of the lower joint body, and the side spraying holes are arranged obliquely upwards. The circulating pup joint is mainly adopted in a drilling and grinding process, and drilling and grinding operation is carried out after reasonable bit pressure parameters are determined; and the speed is increased through an optimized lateral jet flow structure, delivery capacity and tubular columns, dynamic flushing and upward grinding returning are carried out, and finally drilling and grinding circulation is repeated until all work is completed. The pup joint is ingenious in overall structure, long in service life and convenient to operate; and according to the process, the grinding flushing effect can be improved, the continuous pipe drilling plug benefits can be increased, and popularization and application of the technology can be promoted.

Description

technical field [0001] The invention relates to the technical field of oil and gas well development, in particular to a pressure-on-bit control type downhole circulation short connection and continuous pipe drilling plug dynamic flushing technology. Background technique [0002] In recent years, with the large-scale development of shale gas and tight low-permeability oil and gas reservoirs at home and abroad, staged multi-cluster fracturing with drillable bridge plugs in horizontal wells has been widely used. This technology forms a complex fracture network system through clustered perforation and layered fracturing, improves reservoir seepage rate, and has obvious effects on stimulation of shale gas and tight low-permeability oil and gas reservoirs. After completing the fracturing operation in all intervals, using coiled tubing to carry milling tools to drill and grind the residual bridge plugs in the wellbore can not only improve the construction efficiency and save produc...

AI Technical Summary

Problems solved by technology

Even so, in many cases, especially in highly deviated well sections, there will still be some abrasive debris that cannot be returned normally, resulting in the site being forced to lift and lower the pipe string many times, increasing the fatigue damage of the pipe string, deformation, and pipe sticking risk, or use strong magnetic tools to salvage, increasing operation time and cost

As a result, the application and promotion of coiled tubing drilling and grinding bridge plug technology is greatly restricted

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