Drillmax® Model GC

Full Flow Flapper Type Automatic Fill
 
The Model GC is identical to the Model G but adds an automatic fill feature when going in the hole. A control arm holds the flapper slightly open during run in, allowing the valve to fill from the bottom. This removes the requirement for filling the drill pipe from the top, saving time. Similar to the Model G, the valve fully opens when the drill string is raised, preventing environmental and safety risks associated with having mud on the rig floor. The valve operates as a Model G as soon as the mud is pumped down the drill string. The Model GC helps prevent pressure surges that could cause formation damage.