Automatic Blocking Regulating Valve (CRAB)

for injection wells

CRAB combines a packer and a valve that cuts off formation pressure from the wellbore above the packer. The CRAB is lowered on a tubing stock elevator and secured in the wellbore.

• Eliminates discharging the well before well interventions and workovers or stock tubing elevator replacement;
• Eliminates well killing procedure.

• The stock tubing elevator of an injection well is changed without retrieving the CRAB. The tubing elevator is unhooked from the packer and pulled to the surface. CRAB - packer and cut-off valve, blocking the flow of fluid from the sub-packer space of the well to the above-packer space, preventing the well from discharging. A new stock tubing elevator is run into the well and docked to the CRAB and the well is put into operation.

• Stimulation of the formation through acid treatment, fracturing, hydrofracturing, hot treatments, etc. is performed by removing the stock tubing elevator from the CRAB, running and docking the tubing elevator to the CRAB, performing the operation, removing the tubing elevator and re-running the stock tubing elevator into the well with the final connection to the CRAB.