Pantograph underreamer
AssigneeCDX Gas, LLC
InventorsMonty H. Rial, Lawrence W. Diamond, Harold E. Payne
Life of this patent
Estimating the term…
Abstract
An underreamer for forming a cavity within a well bore is provided. The underreamer may include a housing rotatably disposed within the well bore. The underreamer may also include an actuation rod slidably positioned in the housing. The underreamer may further include a plurality of cutter sets where each cutter set is pivotally coupled to the housing and the actuation rod. The cutter sets are also pivotally coupled together. An axial force applied to the actuation rod operates to slide the actuation rod relative to the housing and extend the cutter sets from a retracted position radially outward relative to the housing to form the cavity when the housing is rotated.
Claims21
An underreamer for forming a cavity within a well bore, comprising:
- a housing adapted to be rotatably positioned within the well bore;
- an actuation rod slidably positioned in the housing;
- at least one first cutter, each first cutter having a first end and a second end, each first end pivotally coupled to the housing;
- and
- at least one second cutter, each second cutter pivotally coupled to a respective first cutter, each second cutter having a first end and a second end, the first end of each second cutter pivotally coupled to the actuation rod, wherein an axial force applied to the actuation rod is operable to slide the actuation rod relative to the housing and extend the second ends of the first and second cutters radially outward relative to the housing from a retracted position to form the cavity when the housing is rotated relative to the well bore.
A method for forming a cavity within a well bore, comprising:
- positioning an underreamer within the well bore, the underreamer having a housing and an actuation rod, the actuation rod slidably positioned in the housing, the underreamer further having at least one first cutter and at least one second cutter, each of the first and second cutters having a first end and a second end, the first end of the first cutter coupled to the housing and the first end of the second cutter coupled to the actuation rod, the second end of the first cutter pivotally coupled to the second cutter proximate the second end of the second cutter;
- applying an axial force to the actuation rod;
- extending the first and second cutters radially outward from a retracted position relative to the housing in response to movement of the actuation rod relative to the housing from the applied force;
- and
- rotating the underreamer within the well bore to form the cavity.
Dependencies are inferred from the claim text.