17 Technical Information
Venting Procedure (without Contaminants and/or Corrosive Gases) –
334/342 TwisTorr 74 FS User Manual / 87-901-053-01
Venting Procedure (without Contaminants and/or
Corrosive Gases) – Manual Venting
1 Close the process gases flowing into the system before sending
the STOP signal to the TwisTorr 74 FS pump.
2 Close the gate valve connecting the Turbo pump to the chamber
(if present).
3 Switch off the backing pump or close a fore-vacuum valve (if
present).
4 Turn off the Turbo pump by sending the STOP signal to the
controller.
5 Open the Vent Port (positioned on the envelope) slowly until to
reach atmospheric pressure in the system.
6 For water cooling: shut off the water supply.
CAUTION!
To safely slow down the pump use a venting flow able to decelerate the rotor at
a rate lower than 13-15 Hz/s. Higher deceleration rates could damage the
bearings.