Downhole Milling Tool

摘要

A downhole milling tool (100) operable to remove unwanted debris from an interior wall of a pipeline, well casing or other tubular in which the tool (100) is deployable. The tool (100) comprises a hollow tool body (1, 11) mountable on a drill string and an annular element (8) mountable about an outside surface of the tool body (1). The annular element (8) houses at least one elongate milling blade (12). The at least one milling blade (12) is configured such that it always projects from an outside surface of the annular element (8) and includes an elongate cutting face (36). The annular element (8) is configured to be rotatably coupled to the tool body (1) in an active state and rotatably decoupled from the tool body (1) in an inactive state such that the annular element (8) and the tool body (1) are rotationally dependent when coupled and rotationally independent when decoupled. The cutting faces (36) are each configured to be operable to remove unwanted debris only when the annular element (8) and the tool body (1) are rotationally dependent, such that, in use, rotation of the tool body (1) effects operation of the milling blades (12) to remove unwanted debris and to be inoperable to remove unwanted debris when the annular element (8) and the tool body (1) are rotationally independent.

主权项

1. A downhole milling tool, comprising:
a hollow tool body mountable on a drill string; an annular element mountable about an outside surface of the tool body, wherein the annular element houses a at least one elongate milling blade, wherein the at least one milling blade projects from an outside surface of the annular element; each milling blade includes an elongate cutting face; wherein the annular element is configured to be rotatably coupled to the tool body in the active state and rotatably decoupled from the tool body in an inactive state; wherein the annular element and the tool body are rotationally dependent when coupled and rotationally independent when decoupled; wherein the cutting faces are each configured to remove unwanted debris only when the annular element and the tool body are rotationally dependent, such that, in use, rotation of the tool body effects operation of the milling blades to remove unwanted debris; and wherein the cutting faces are inoperable to remove unwanted debris when the annular element and the tool body are rotationally independent.