Rotating claws beef up vacuum system Gardner Denver now offers the Oil-Free Claw Vacuum System with two-shaft and rotary lobe vacuum pumps. In the claw system, two claws within housing rotate dry and without contact in opposite directions, synchronized by a pair of gears. The pumping chamber is oil-free. Synchronized drive gears and the A-side bearings for the rotors are oil lubricated. Vacuum to 25.5" HgV and pressure to 32psig.