Patent ID: 8356671

Claim:
A tool for use in subterranean hydrocarbon production, the tool comprising: a housing defining an axial flow bore; a piston sleeve axially moveably disposed within the flow bore between a first position corresponding to a first operating position for the tool, and a second position corresponding to a second operating position for the tool; an actuation mechanism for moving the tool between the first and second operating positions, the actuation mechanism comprising a partially annular ball seat associated with the piston sleeve, the ball seat comprising: an arcuate base; h a plurality of retaining segments projecting radially inwardly from the base and separated from one another by gaps, the retaining segments each presenting an upper seating surface for a ball; a central opening defined within the retaining segments; wherein: a) the actuation mechanism moves the tool from the first operating position to the second operating position by landing a first actuation ball onto the ball seat and thereafter varying fluid pressure within the flow bore of the housing; and b) the actuation mechanism moves the tool from the second operating position to the first operating position by landing a second actuation ball that is of a different size that the first actuation ball onto the ball seat and thereafter varying fluid pressure within the flow bore of the housing.