Piston Vacuum Pumps

What are piston vacuum pumps?

Like some others, piston pumps are oil-free, and they create a vacuum via a piston pushing up and down in a cavity with one-way valves. The one-way valves in the pump pull down and draw air into the pump body. The piston then pushes out the air by thrusting upwards into the cavity and pushing open another one-way valve, expelling the air.