Expandable ball seat for hydraulically actuating tools

摘要

A downhole tool has a housing, a mandrel, a seat, and a piston. The housing defines a first bore, and the mandrel is movably disposed in the first bore and defines a second bore. The mandrel has first and second mandrel sections or upper and lower cones, and the first mandrel section defines a cross-port communicating the second bore with an annular space between the mandrel and the housing. The seat is disposed in the first bore of the housing between the first and second mandrel sections. The seat is movable to a constricted state in the first bore to catch a dropped ball and is movable to an expanded state in the first bore to pass a dropped ball. The piston is disposed in the annular space and at least temporality supports the seat in its constricted state.

主权项

1. A downhole tool, comprising:
a housing for use downhole defining a first bore; a mandrel disposed in the first bore and defining a second bore, the mandrel having first and second mandrel sections, the first mandrel section defining a first cross-port for communicating fluid in the second bore with an annular space between the mandrel and the housing; a seat disposed in the first bore of the housing between the first and second mandrel sections, the seat movable to a constricted state in the first bore and movable to an expanded state in the first bore; and a piston disposed in the annular space, the piston in a first position at least temporality supporting the seat in the constricted state, the piston movable in response to the communicated fluid to a second position removing the at least temporary support of the seat.