Positive Displacement Pump
Dresser and Roots are the leading positive displacement blower manufacturers. Varisco specializes in positive displacement pumps for liquids of all viscosities from 1/2" to 12". Roots manufactures PD blowers that range from 2 cfm to 250,000 cfm with prssures to 30 psig and single stage vacuums to 28" Hg. The flow through a PD or positive displacement blower is relatively constant regardless of pressure changes.
