Cementing Head

A tool for dropping one or more balls and then one or more darts features a closable ball drop opening that works automatically after the ball release to minimize damage to the subsequently released dart. A retainer keeps the darts from coming back up above the dart launcher in the event of a pressure surge in the well. The dart launcher features a dedicated movable barrel for each dart that can be locked in a fully misaligned and fully aligned position with the casing or tubular. A handle (14) is retained to the dart housing and can be manipulated to defeat the lock and rotate a given barrel. The darts may be inspected in their respective barrels before launch and the launch order is variable.