MD 4 VARIO select VARIO® diaphragm pump, 100-115 V, 50-60Hz, 120 V, 60Hz

This three-stage diaphragm pump is an excellent solution for continuous, oil-free pumping of non-corrosive gases to a vacuum level as deep as 1 mbar. All wetted parts are made of aluminum, stainless steel and carefully selected plastics suitable for a wide range of applications with non-corrosive gases. The MD 4 VARIO select continuously adapts its motor speed to hold the desired vacuum level. That means the pump is whisper-quiet and generates ultra-low vibrations, and has high leak tightness. The highly flexible fabric-reinforced double FKM diaphragm is ideal for extended operating life. The VARIO design includes the variable speed pump and the VACUU·SELECT vacuum controller with external gauge head. The demand-responsive motor speed control on VARIO models further extends the already long lifetimes of diaphragms and valves. These three-stage diaphragm pumps are an excellent choice for continuous, contamination-free evacuation and pumping of non-aggressive gases at demanding vacuum conditions. They are especially suitable for applications requiring high volume flow in physics and analytics. The low ultimate vacuum makes these an attractive alternative to rotary vane pumps. Typical uses are as backing (roughing) pumps for turbomolecular drag pumps, for degassing of viscous media, as well as for exhaust gas analytics. Additionally, the VARIO®model provides vacuum control by precise adjustment of the diaphragm pump´s motor speed to process requirements. Back diffusion of oil or even oil back flow, e.g., into a high vacuum chamber is excluded due to its oil-free operation. For equipment manufacturers customized versions are available. Depending on the application the demand-responsive motor speed control of VARIO®models further extends the long diaphragm life for which VACUUBRAND pumps are well-known. In additon it provides an even higher pumping speed and enables precise vacuum control.