Patent ID: 8276690
Filing Date: 2012-10-02
Classification: E21B

Abstract:
1. An expandable downhole tool for incorporation in a drillstring, the tool capable of being adjusted between activated and deactivated modes, said tool comprising: a tool body; a working component mounted indirectly on the tool body for movement relative to the tool body between a withdrawn inoperative position and an outwardly deployed operative position corresponding respectively to the deactivated and activated modes of the tool; a mandrel slidably mounted in the main body for axial movement between first and second positions, said mandrel taking up the first axial position in the deactivated mode of the tool and being displaceable to the second axial position in order to activate the tool to its activated mode; a spline bar mountable in a recess in the tool body and defining an outwardly extending guide path, wherein the spline bar defines a linear guide path extending parallel to the axis of movement of the mandrel, in which the linear guide path is defined by the axis of the spline bar, and the outwardly extending guide path is defined by a sloping guide ramp provided on the spline bar; and at least one first travel block coupled with the mandrel for movement therewith; in which the working component is mountable on the spline bar for movement along said outwardly extending guide path, the at least one said first travel block being engageable with the working component as the mandrel moves from its first position to its second position in order to move the working component along the outwardly extending path from its withdrawn position to its outwardly deployed position.