[labnetwork] Automated N2 shutoff for dry pumps

[Carsen Kline]

Hello all,

The topic of nitrogen cost is a common thread within this group, and 
many of you have found creative solutions to reduce N2 usage on dry pump 
purges. It is my understanding from reading your comments and from 
talking to a dry pump repair outfit that continuous N2 feed is not 
necessary in many of our applications and in some cases can be 
comfortably converted to CDA.

For those pumps that require nitrogen, but have an active process duty 
that doesn't justify the amount of N2 they consume, we're looking for an 
automated solution to switch off or reduce N2 flow during system idle 
time. It's been recommended to me by one vendor that N2 should flow for 
30 minutes following process, but after this could be shut off or reduced.

Rather than reinvent the wheel that some of you may already have in 
service, I'd like to ask if anyone could share a design for such a timed 
system with a provision for tying it to an enable/disable system (such 
as Badger/Coral/FOM). I'd be interested in detailed plans or even 
complete units that we could purchase outright. My contact information 
is listed below.

Many thanks, I look forward to your feedback.

Carsen

-- 
Carsen Kline
Stanford Nanofabrication Facility
Paul G. Allen Bldg 141, Mail Code 4070
Stanford, CA  94305
(650)724-8214
carsen at stanford.edu
http://snf.stanford.edu