08602115 is referenced by 9 patents and cites 51 patents.

A tractor configured for grip locking during advancement to avoid slippage, particularly in open-hole wells. The tractor is equipped with a grip lock mechanism for independently locking an anchor grip in a radially outward direction. This locking occurs sequentially in advance of the power stroke of a reciprocating drive piston associated with the anchor. Thus, radial outward expansion and gripping are ensured at the time pulling of a load in an axial downhole direction is pursued. Such grip locking may be employed throughout tractoring or intermittently, depending upon well characteristics such as formation hardness and well diameter.

Title
Grip enhanced tractoring
Application Number
12/628380
Publication Number
8602115 (B2)
Application Date
December 1, 2009
Publication Date
December 10, 2013
Inventor
Derek Copold
Sugar Land
TX, US
Mark Holly
Sugar Land
TX, US
Wade D Dupree
Sugar Land
TX, US
Franz Aguirre
Missouri City
TX, US
Agent
Jody DeStefanis
John Vereb
Trevor Grove
Assignee
Schlumberger Technology Corporation
TX, US
IPC
E21B 4/18
E21B 23/01
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