vacuum pump

[santoshdada]

Dear Friend
we are using a root pump befor liquid ring pump to boost the vapour medium now problem is that suddnly vacuum changed from 0.00 torr to 13 torr now what may be proabable reason. we took following action

1)complete line cleanig for any chocking

2)leakage checked there is no lekage

after doing all above activity we did not found any improvement

then we change root pump(twin lobe type) both side lube oil(fresh vacuum oil P3) as we found temp is high(80 Deg) on both side after that we again started the system then we found 0.00 torr again, now i am not able to uderstand how it happend

we tested the lube oil sample(used one) on our laboratry we found 10% mixing of glycol vapour(pumping medium) on the lub oil

now i fully confused how vacuum break from 0.0 torr to 10.0 torr

is thr any link with lube oil ??

or there are some othe reason?

mixing of glycol indicate there may be lekage from sealing but now how it is working well

plz help me any one from ths field

thx in advance

 

[Oxidation]

Are you controlling the 2 stage vacuum process correctly??
The booster blower (roots) will overload the vacuum pump if you do not keep the DP to less than 200mbara.
I've worked with LRVP & BB on several installations & found that there has always been problems with BB seal oil failure when the medium pumped is miscible with the oil.