Rubicon Top-Co Differential Fill Float Equipment

Type 535 Differential Fill Float Collar and Type 536 Differential Fill Float Shoe allow for automatic filling and leveling of the fluid within the casing while it is being run in the hole. The differential fill float equipment consists of a sleeve that operates under differential pressure allowing the inflow of fluid to fill the casing 80-90% before shifting closed from the fluid
pressure acting above the valve. The automatic filling action reduces casing running time and minimizes surge pressures on formations. The valve is converted to a conventional one way check valve by dropping a ball from surface, pressuring up to release the upper flapper, and locking the shifting sleeve against the bottom flapper. Until the conversion ball has been dropped, the casing can be circulated at any time without affecting the fill-up operation.