Abstract: A downhole tool comprises a body having a slot therein, a cutting blade mounted within the body and extendible and retractable through the slot such that the outer diameter of the tool can be selectively increased, an actuation member for driving the cutting blade between the retracted and extended positions and a mounting means connecting the blade to the actuation member, said body having a tapered surface along which the blade travels such that as the blade travels along the tapered surface the blade moves radially outwardly with respect to both the body and the mounting means whilst remaining in contact with the tapered surface.

Abstract: A connection apparatus is adapted to allow connection of one substantially tubular member to another substantially tubular member. The connection apparatus includes a male connecting member and a female connecting member. Cooperating attachment mechanisms are provided on the male and female connecting members. Each of the male and female connecting members includes at least one primary surface adapted to form a primary joint and at least one secondary surface adapted to form a secondary joint. The at least one primary surface may be adapted to form a primary load bearing shoulder joint. The at least one secondary surface may be adapted to form a secondary load bearing shoulder joint. The connection apparatus may provide a double shoulder high torque connection for downhole tubular members. A double acting hydraulic jar is also disclosed.

Abstract: A connection apparatus (C3) and method for connecting a male screw threaded connection (118) provided on one tubular member (114) to a female screw threaded connection (120) provided on another tubular member (116) has an over-torque indicator (115) comprising an observable point (114E, 130) provided on at least one of the male (114) and female (116) screw threaded members where the observable point (114E, 130) provides an indication if the male screw threaded connection (118) has been over-torqued into the female screw threaded connection (120).

Abstract: An impact enhancer apparatus includes: a substantially tubular inner member, a substantially tubular outer member that is axially movable in relation to the inner member, a primary energy storage device adapted to store energy when the inner member is moved in either of first and second axial directions with respect to the outer member and a secondary energy storage device adapted to store energy when the inner member is moved in a first axial direction with respect to the outer member. The primary energy storage device may include a primary biasing device. The secondary energy storage device may include a secondary biasing device. The primary and/or secondary biasing devices may be a spring device such as a disk spring, a coiled spring, a fluid spring, a gas spring, etc. The impact enhancing devices may include tubular members that have double shoulder high torque connections.

Abstract: A connection apparatus is adapted to allow connection of one substantially tubular member to another substantially tubular member. The connection apparatus includes a male connecting member and a female connecting member. Cooperating attachment mechanisms are provided on the male and female connecting members. Each of the male and female connecting members includes at least one primary surface adapted to form a primary joint and at least one secondary surface adapted to form a secondary joint. The at least one primary surface may be adapted to form a primary load bearing shoulder joint. The at least one secondary surface may be adapted to form a secondary load bearing shoulder joint. The connection apparatus may provide a double shoulder high torque connection for downhole tubular members. A double acting hydraulic jar is also disclosed.

Abstract: An impact enhancer apparatus includes: a substantially tubular inner member, a substantially tubular outer member that is axially movable in relation to the inner member, a primary energy storage device adapted to store energy when the inner member is moved in either of first and second axial directions with respect to the outer member and a secondary energy storage device adapted to store energy when the inner member is moved in a first axial direction with respect to the outer member. The primary energy storage device may include a primary biasing device. The secondary energy storage device may include a secondary biasing device. The primary and/or secondary biasing devices may be a spring device such as a disk spring, a coiled spring, a fluid spring, a gas spring, etc. The impact enhancing devices may include tubular members that have double shoulder high torque connections.