The Challenge

Recovering casing from partial cement, settled solids and shifting formations can be extremely challenging. Some drilling rigs have limited pulling capacity, and a substantial amount of that power is lost to friction in the drill string between the top drive and the casing spear, leaving insufficient power at the spear to recover the casing.

The Solution

The DownHole Power Tool (DHPT), with its superior pulling capacity, can recover more casing per operation compared to conventional pulling with the rig. The DHPT's pulling forces are applied locally in the well and there is no loss of force due to drill string friction. This maximises the ability to pull stuck or packed off casing, and makes high force operations possible even in rigs with limited pulling capacity.

The Down Hole Power Tool (DHPT) retrieves casing/fish in applications where the drilling rig or work string does not have sufficient capacity and can be used as a replacement for surface casing jacking systems.

After the casing has been located and engaged, hydraulically-set mechanically releasable slips anchor the DHPT to the wall of the larger ID casing above.

Pressure is applied to begin the upward movement of the fish, with the DHPT downhole multi-stage hydraulic actuator functioning as a hydraulic jack.

After the stroke is completed, the anchors are released. The power section can be reset and the anchor re-engaged as many time as required.