The Formation Saver Sub (FSS) is a tubing mounted sub that permits setting hydraulic tools above without surging the formation.The FSS releases the seat upon relieving the tubing pressure within a small delta of the formation pressure. Several sizes are now in prototype testing.
Features:
- Eliminates premature blowing of ball seat.
- Prevents a surge of fluid into the formation.
- Allows higher pressure than the shear value without losing seal integrity.
- Will not release until a small pressure delta on the tubing is achieved.
- Ball seat held in by dogs instead of shear screws.
- Shear value customizable to well.
- Full bore when seat released.
- Carbon and exotic material available.
- Non-elastomeric available.