Isolation Valve Cleanup Subs
Remove debris above ball-type isolation valves
Clean up isolation valves with jetting or circulation subs to reduce the risk that debris will hinder valve operation.
Mechanically controlled isolation valve
The valve also provides a two-way barrier during remedial work (e.g., removal and reinstallation of an ESP or the production tubing), underbalanced perforating, and general completion operations.
Operated mechanically with a shifting tool run on the end of washpipe, a perforating string, or CT, the MFIV-II valve can be opened and closed multiple times. It uses the same ball sealing design and latch collet system used in the FIV-II formation isolation valve.
The MFIV-II valve is qualified with gas to a zero-bubble leak rate across the ball from below under specified conditions. This stringent acceptance criterion enables the tool to be used as a barrier before production starts; subsequently the valve can be used as a fluid loss control device for well intervention operations, well suspension, and temporary abandonment.