Problem metalica SNF 2012-04-25 05:50:17: Roughing pump doesn't function

[kokab at snf.stanford.edu]

I started running the process without problem and everything during the process was okay. after finishing the run I opened the roughing valve and it started with lots of noise and didn't ended with that, I waited for 10min for the pressure to go higher than 150mT but nothings happen then I closed the roughing valve since the noise was getting worse and worse.