Two stage blowers use an additional impeller to create higher pressures. As a general statement, two stage blowers generate higher pressure with lower flow when compared to single stage blowers with compatible HP.
Below is the regenerative blower model matrix for two stage units. Pressure and vacuum ratings are maximum readings at minimum air flow. Air flow measurements are taken in a “free flow” condition, without any system pressure drop.
See individual data sheets for curves specific to each model. Make sure the application requirements – flow and pressure combination – are a point below and to the left of the curve for a given blower.