| 摘要 |
Expandable reamers are configured to operate in a first, retracted state in which a plurality of blades is in a retracted position when a sliding sleeve is in a first sleeve position and a seat is in a first seat position, to operate in a second, extended state in which the plurality of blades is movable to an extended position when the sliding sleeve is in at least a second sleeve position and the seat is in the first seat position, and to operate in a third, retracted state in which the plurality of blades is returned to the retracted position when the sliding sleeve is in the at least a second position and the seat is in a second seat position. |
| 主权项 |
1. An expandable reamer for use in a borehole in a subterranean formation, comprising:
a housing defining a central bore; a plurality of blades carried by the housing and movable between a retracted position and an extended position responsive to flow of drilling fluid; a sliding sleeve disposed within the central bore and coupled to the housing, defining an axial fluid passageway, and comprising at least one port in a sidewall of the sliding sleeve, the sliding sleeve being movable between a first sleeve position and at least a second sleeve position to alter flow of drilling fluid; a seat disposed within and coupled to the sliding sleeve, the seat being movable between a first seat position and a second seat position to alter flow of drilling fluid; and at least one sealing member configured to form a seal between the housing and the sliding sleeve and to inhibit fluid flow in a space defined between the housing and the sliding sleeve between a first side of the at least one sealing member and a second, opposing side of the at least one sealing member when the at least one sealing member is engaged with the housing and the sliding sleeve, the at least one port in the sidewall of the sliding sleeve being located on the first side of the at least one sealing member in the first sleeve position and movable to the second, opposing side of the at least one sealing member when the sliding sleeve is in the at least a second sleeve position, wherein the expandable reamer is configured to operate in a first, retracted state in which the plurality of blades is in the retracted position when the sliding sleeve is in the first sleeve position and the seat is in the first seat position, to operate in a second, extended state in which the plurality of blades is movable to the extended position when the sliding sleeve is in the at least a second sleeve position and the seat is in the first seat position, and to operate in a third, retracted state in which the plurality of blades is returned to the retracted position when the sliding sleeve is in the at least a second position and the seat is in the second seat position. |
