Hydraulic/mechanical tight hole jar

摘要

A jar comprises a housing including an anvil. In addition, the jar comprises a mandrel telescopically disposed within the housing and including a hammer. Further, the jar comprises an annular chamber radially positioned between the mandrel and the housing. Still further, the jar comprises an actuation assembly disposed in the annular chamber. The actuation assembly includes a first collet disposed about the mandrel, a first trigger sleeve disposed about the first collet and adapted to releasably engage the first collet, and a first biasing member adapted to exert an axial force on the mandrel. Moreover, the jar comprises a lock assembly disposed in the annular chamber. The lock assembly includes a second collet disposed about the mandrel, a second trigger sleeve disposed about the second collet and adapted to releasably engage the second collet, and a second biasing member adapted to exert an axial force on the mandrel.

主权项

1. A jar having a longitudinal axis, comprising:
a housing including an anvil; a mandrel telescopically disposed within the housing and including a hammer; an annular chamber radially positioned between the mandrel and the housing; an actuation assembly disposed in the annular chamber, the actuation assembly including:
a first collet disposed about the mandrel and adapted to releasably engage the mandrel, wherein the first collet is axially moveable between a neutral position engaging the mandrel and a triggered position disengaged from the mandrel;a first trigger sleeve disposed about the first collet and adapted to releasably engage the first collet;a first biasing member adapted to exert an axial force on the mandrel upon compression of the first biasing member by movement of the mandrel in a first axial direction relative to the housing when the first collet is in the neutral position; a lock assembly disposed in the annular chamber, the lock assembly including:
a second collet disposed about the mandrel and adapted to releasably engage the mandrel, wherein the second collet is axially moveable between a neutral position engaging the mandrel and a triggered position disengaged from the mandrel;a second trigger sleeve disposed about the second collet and adapted to releasably engage the second collet;a second biasing member adapted to exert an axial force on the mandrel upon compression of the second biasing member by movement of the mandrel in the first axial direction relative to the housing when the second collet is in the neutral position; wherein the lock assembly is adapted to release the mandrel, and wherein the actuation assembly is adapted to release the mandrel and allow to the hammer to axially impact the anvil.