Gast oil-free regenerative blowers

Gast Regenair regenerative blowers are oil-free units for applications that require large air volumes with vacuum or compressed air. In a regenerative blower, a certain amount of air slips past each impeller blade during rotation and is returned to the root of the next blade to be accelerated again. The compression space consists of a hollow, circular ring between the blade tips and the housing wall; the rotating impeller draws air in from the inlet and drives it radially outwards towards the housing by centrifugal force. Because of this dynamic principle, regenerative blowers can deliver pressure and vacuum performance comparable to multi-stage or positive displacement blowers. The series covers air flows up to 1350 cfm (2294 m³/h). The motor-mounted models deliver pressure up to 125 inH2O (311 mbar) and vacuum up to 115 inH2O (286 mbar); the belt-driven SDR5 and SDR6 deliver higher pressure and vacuum.

Motor-mounted models range from the R1 at 1/8 hp (23/27 cfm at 50/60 Hz) via the R2, R3, R4, R4P, R5, R6 and R6P to the largest R7, R7P, R9 and R9P at 10–30 hp. The belt-driven SDR4, SDR5 and SDR6 (4–15 hp) make it possible to lower the speed and adapt the performance by changing the pulley size; they have built-in acoustic damping and precision-balanced impellers for low vibration. R1, R2, R3, R4, R4P, R5 and R7 can be mounted in any plane, while R6 and R6P must stand horizontally with the foot plate down and R7P, R9 and R9P with a horizontal shaft. The blowers provide a continuous, pulse-free air flow.

The standard models have a robust construction in cast aluminium or cast iron depending on model size, UL- and CSA-approved motors (TEFC on single-shaft models, open on double-shaft models), permanently sealed ball bearings with polyurea grease and integrated silencers on single-shaft models. Dedicated models with explosion-proof motors from 1/2 to 10 hp are designed for soil vapour extraction; these have thermal protection and double-sealed ball bearings. Typical applications are air tables, agitation of liquids and media, vacuum hold-down and pick-up, blow-off, soil and groundwater remediation, carton forming and packaging, laboratory filtration, sewage aeration, material handling, aquaculture and pneumatic conveying.