Uninterrupted circulating valve

Abstract

The invention discloses an uninterrupted circulating valve. The uninterrupted circulating valve comprises a casing, a main channel and a bypass channel, wherein the casing is cylindrical, threads are formed in the upper end and the lower end of the casing, a through hole A and hole channels A are axially formed in the casing, and a hole channel B is radially formed in the casing; a spring seat, a spring, a valve element and a valve seat are mounted in the through hole A from top to bottom; a through hole B is processed in the axial center of the spring seat, and axial through holes C are formed in the outside part of the through hole B; the middle of the valve element adopts a conical structure and forms a taper angle seal with a conical chamfer at the upper part of the valve seat. The uninterrupted circulating valve has the advantages that with the adoption of a manure one-way valve seal form, the fluid sealing reliability of the uninterrupted circulating valve is improved. Through continuous circulation in the drill pipe connection period, pressure fluctuation of a wellbore due to drill pipe connection operation is effectively avoided, the wellbore quality and cleanness are improved, the probability of leakage, well kick, pipe sticking and other complicated problems is reduced, the non-productive time is reduced, and a stratum which cannot be drilled previously is drilled.

Description

technical field [0001] The invention relates to the field of petroleum exploration and development tools, in particular to an uninterrupted circulation valve used in continuous circulation drilling. Background technique [0002] When a single connection is required for conventional drilling, the circulating drilling medium (mud or gas) must be interrupted. Interruption of circulation can have many adverse effects on drilling operations. Mainly include: when the circulation is stopped, the dynamic pressure drop of the annulus disappears, and the bottom hole pressure decreases, sometimes causing a well kick; when the circulation is re-established, the bottom hole pressure increases, which may lead to lost circulation. These two effects are more prominent when working in a narrow density window. In the highly deviated section and horizontal drilling of extended-reach wells, cuttings will fall on the lower side of the wellbore to form a cuttings bed, which reduces the effectiv...

AI Technical Summary

Problems solved by technology

These adverse effects are likely to cause drilling complications such as wellbore instability, wellbore collapse, stuck pipe, drilling tool failure, overflow or lost circulation.

Images