A high vacuum pump built from alternating rows of angled rotor and stator blades, spinning at roughly 20 000 to 90 000 rpm so the blade tips move at several hundred metres per second, comparable to the speed of the molecules themselves. Molecules that strike the blades pick up momentum toward the outlet. It works only in molecular flow, needs a backing pump, and compresses heavy gases far better than hydrogen and helium; many models add a molecular drag stage that tolerates a higher backing pressure.
Turbo's at full speed and the foreline's at 1E-2, open the gate and let's see where base lands by morning.
Never let a spinning turbo take a sudden burst of air; vent through a slow vent valve or let it spin down to about half speed first.
Also heard as
- turbo
- TMP
- turbopump
- turbo pump
Related terms
At speed
Said of a turbo pump that has finished spinning up and reached its normal rotational speed.
Crash a turbo
To wreck a turbo pump's rotor by letting it hit the stator, most often by venting it hard while it spins.
Spin down
Of a turbo pump, to coast down from full speed after it is switched off, which takes many minutes on its own.
Compression ratio
Ratio of a pump's outlet pressure to its inlet pressure for a given gas, measured at zero net flow.
Backing pump
Pump that keeps the exhaust of a turbo, diffusion or Roots pump below its maximum allowed pressure.