Patent ID: 6119783
Filing Date: 2000-09-19
Classification: E21B

Abstract:
Indexing apparatus operatively positionable within a subterranean wellbore, the apparatus comprising:first and second tubular members, the second tubular member being movably received within the first tubular member, and each of the first and second tubular members having inner and outer side surfaces formed thereon;a piston having a differential pressure area, the piston being displaceable relative to the first tubular member between a first position and a second position;a first grip member, the first grip member being displaceable with the piston between the first and second positions; anda second grip member, the second grip member preventing displacement of the second tubular member in a first direction relative to the first tubular member,the first grip member forcing the second tubular member to displace in a second direction opposite to the first direction when the piston displaces from the first position to the second position.