The RIGGER ENGINEERING fast actuating cementing head provides a convenient method of maintaining mud/cement separation following the cement pumping operation. The single, two-way valve is the key to its rapid and efficient plug initiation. Operation is simple and fool proof. The plug is installed into the cavity located in the top portion of the head. The indicator line on the valve must be at 90 degrees to the drill pipe. Next, the actuating lever is installed in the valve-locking hole, thereby preventing any chance accidental valve movement. The drill pipe plug remains in the upper cavity of the cement head while cement is pumped through the lower part via the two-way valve. Following the cement pumping operation, the valve is rotated 90 degrees and the drilling mud is directed to the top of the cement head via a bypass tube. Mud pressure forces the dart through the cement head and into the drill pipe, maintaining cement/mud separation. The indicator line on the face of the valve points in the direction of the plug movement. A stop mechanism precisely aligns the valve position. It is impossible to send the dart down the drill pipe until the valve is rotated 90 degrees and the line is parallel to the drill pipe. Another positioning hole is provided allowing one to insert the actuating lever, locking the valve in the open position.