The disclosure of this application is directed to a downhole tool comprising a central element/member and a sleeve that is rotatably and orbitally disposed around the central element/member. The sleeve rotates and orbits around the central element/member responsive to fluid flowing through the downhole too. The disclosure is also related to a method of advancing the downhole tool in a well by flowing fluid through the tool.

The disclosure of this application is directed to a downhole tool comprising a central element/member and a sleeve that is rotatably and orbitally disposed around the central element/member. The sleeve rotates and orbits around the central element/member responsive to fluid flowing through the downhole too. The disclosure is also related to a method of advancing the downhole tool in a well by flowing fluid through the tool.

The disclosure of this application is directed to a downhole tool comprising a central element/member and a sleeve that is rotatably and orbitally disposed around the central element/member. The sleeve rotates and orbits around the central element/member responsive to fluid flowing through the downhole too. The disclosure is also related to a method of advancing the downhole tool in a well by flowing fluid through the tool.

The disclosure of this application is directed to a downhole tool comprising a central element/member and a sleeve that is rotatably and orbitally disposed around the central element/member. The sleeve rotates and orbits around the central element/member responsive to fluid flowing through the downhole too. The disclosure is also related to a method of advancing the downhole tool in a well by flowing fluid through the tool.

A tool assembly (10) comprises a casing section (12), and a downhole tool (14) comprising a rotary drive (16) and a cutting member (18). In use, the tool assembly (10) is disposed in a well borehole (B) and the rotary drive (16) operated to drive rotation of the cutting member (18) to cut the borehole (B). The downhole tool (14) comprises a tubular housing (20) and a cartridge assembly (36), the cartridge assembly (36) disposed within the housing (20) of the downhole tool (14) and comprising the rotary drive (16) of the downhole tool (14). A clutch (78) is provided to enable free movement of the cutting member (18) during normal operation, engagement of the clutch (78) preventing rotation of the cutting member (18) and the housing (20).

The present invention relates methods and apparatus for lining a wellbore. In one aspect, a drilling assembly having an earth removal member and a wellbore lining conduit is manipulated to advance into the earth. The drilling assembly includes a first fluid flow path and a second fluid flow path. Fluid is flowed through the first fluid flow path, and at least a portion of which may return through the second fluid flow path. In one embodiment, the drilling assembly is provided with a third fluid flow path. After drilling has been completed, wellbore lining conduit may be cemented in the wellbore.

A completion system comprises tubular components coupled together to form a completion string. In-flow control devices are provided to permit selective fluid communication between an internal bore of the completion string and the annulus. A reaming tool is provided at a leading end of the completion string and the reaming tool is run into the borehole with the completion string. The reaming tool comprises a fluid-powered drive unit, a reaming body and a reaming nose. In use, the completion string is located in the borehole and fluid is directed to the reaming tool to facilitate reaming of the borehole. A second tubular in the form of a washpipe may extend through an internal bore of the completion string for providing fluid to the reaming tool. The reaming tool is operable at a fluid pressure below a pressure which would activate the in-flow control devices.