Patent ID: 7552777

Claim:
An apparatus for setting a downhole tool in existing well fluid, comprising: a mandrel comprising an actuating component assembly relatively moveable thereto for selective actuation of the downhole tool; a restraining member, having a longitudinal axis, said restraining member acting on said actuating component assembly, said restraining member remaining operative for delivery of the downhole tool to near the position where said actuating component assembly will then be actuated by release of compressive loading acting on said actuating component assembly, and whereupon said delivery, a delay period is triggered that terminates with the release of said actuating component assembly by said restraining member by virtue of a developed inability of the restraining member to resist said compressive force which results in a collapse along said longitudinal axis of said restraining member without shear of said restraining member, responsive to exposure of said restraining member to said existing downhole fluid, for automatic setting of the downhole tool; said developed inability of said restraining member comprises weakening from at least one of temperature of the well fluids and duration of exposure to said existing well fluids; said weakening comprises dissolving said restraining member.