PLUG FOR WELL DRILLING PROVIDED WITH RING-SHAPED RATCHET STRUCTURE

摘要

A plug for well drilling comprising a mandrel and members attached on an outer circumferential surface orthogonal to an axial direction of the mandrel, wherein at least one of the members or the mandrel is formed from a degradable material; a ring-shaped ratchet structure formed from a plurality of interlocking parts that allows movement of the member in one direction along the axial direction of the mandrel and restricts movement in the opposite direction is provided on an inner circumferential surface of the member and the outer circumferential surface of the mandrel; preferably further comprising a pushing jig including a ratchet structure and a ring-shaped plate adjacent to the axial direction leading side of the pushing jig. Additionally, a well drilling method using the plug for well drilling, comprising degrading a part or all of the plug after blocking a borehole.

主权项

1. A plug for well drilling comprising:
a mandrel; and members attached on an outer circumferential surface orthogonal to an axial direction of the mandrel; a) at least one of the members or the mandrel being formed from a degradable material, and b) a ring-shaped ratchet structure orthogonal to the axial direction of the mandrel being provided on an inner circumferential surface of at least one of the members and the outer circumferential surface of the mandrel, the ring-shaped ratchet structure being formed from a plurality of interlocking parts that allow movement of the member in one direction along the axial direction of the mandrel and restrict movement in the opposite direction.