Abstract: A nose seal for forming a fluid seal with a sealing surface in a bore The nose seal is particularly suitable for use in high pressure and high temperature conditions. The nose seal includes a substantially deformable sealing ring, which can form a resilient fluid seal with the sealing surface, and a substantially rigid ring, which prevents or limits extrusion of the substantially deformable sealing ring in high temperature and/or high pressure environments.

Abstract: An indexing mechanism is disclosed that can put a tool in a variety of positions while downhole in the face of high static and dynamic loads. In the preferred application, the mechanism controls a movable sleeve on a downhole choke. It contains an indexing feature comprising a pin movable in a series of slots. A piston restrained to move longitudinally engages and rotates an index sleeve to allow the pin to advance into the next J-slot track. A separate lug on the piston engages a radial face on the index sleeve to take the shock load and position the choke instead of allowing the pin to load against the closed end of the slot.

Abstract: An indexing mechanism is disclosed that can put a tool in a variety of positions while downhole in the face of high static and dynamic loads. In the preferred application, the mechanism controls a movable sleeve on a downhole choke. It contains an indexing feature comprising a pin movable in a series of slots. A piston restrained to move longitudinally engages and rotates an index sleeve to allow the pin to advance into the next J-slot track. A separate lug on the piston engages a radial face on the index sleeve to take the shock load and position the choke instead of allowing the pin to load against the closed end of the slot.