**Rotary Piston, Compound Vacuum Pump, 3/60 wired 460V

A direct-coupled motor drives Vacuum Pump Model VP-KTC-21. Oil is used for both lubrication and sealing and is controlled, on-off, by two solenoid valves. The pump has an adjustable gas ballast valve, which increases the vapor handling capacity of the pump. The cylinder is air-cooled and contains three rotary pistons, two of which make up the high vacuum stage, which is located at the suction end of the pump. The third piston forms the backing stage, which draws the gas from the high vacuum stage and exhausts it through the discharge valve, along with the excess oil, into the oil/gas separator. When the oil and gas are separated the oil is returned to the reservoir for recirculation and the gas is released through the breather filter to atmosphere. The pistons are driven by cams arranged on the drive shaft to dynamically balance the moving parts. The effect of this balancing principle renders the pump virtually vibrationless when running. Mounting pads are provided to absorb the starting force plus the residual vibrations and prevent their transmission to the support. The pump can operate on any structure capable of supporting the weight.