Hi Vinay Sharma
common practice is to have an isolating valve upstream and downstream of the control valve, and a throttling valve in the bypass line. The isolating valves are so the control valve can be isolated for servicing, and the throttling valve provides some degree of flow/pressure regulation (sometimes manual operation) during control valve servicing.
Cheers
Steve McKenzie
-----Original Message-----
From: ETSMech User Babrala [mailto:btsmuser@tatachemicals.com]
Sent: Thursday, October 23, 2003 10:19 PM
To: 'PipingDesign@yahoogroups.com'
Subject: RE: [PipingDesign] RE: Water Jet Ejectors
Friends,
I have a doubt regarding the kind of valves to be placed in a control valve
loop.
There are two issues ???
Regards,
Vinay Sharma.
-----Original Message-----
From: Steve McKenzie [SMTP:Mechproj@xtra.co.nz]
Sent: Thursday, October 23, 2003 2:35 PM
To: <a href="/group/PipingDesign/post?postID=laTh_c1oO8Da10gwW4EUH_SJBiCFfKqFFfKUyto6gRWDpf_RxtUGEjGdjFFZQ-OPn6s5XwhrMrrqJ4IfLMonsIJ4VB1vkLo">PipingDesign@yahoogroups.com</a>
Subject: RE: [PipingDesign] RE: Water Jet Ejectors
Hi Shah M. Tanweer
I think we have come to the branch in the road.
As far as "size" goes it is quite clear in the S&K website downloads
that it
refers to the suction and the discharge connections in inch NB. Have
you
looked at these? It also gives a sizing procedure.
I suspect that if you do need 1300gpm to do the job, then the low
efficiency
of an ejector will make it a bad choice for continuous duty. Unless
you
specifically need an ejector then I suggest you look at alternatives
such as
liquid ring vacuum pumps. Or perhaps you need something like a jet
scrubber.
It is impossible to select as you have provided no process
conditions.
If you wish to persist with the ejector you could try contacting S-K
with an
enquiry; I have found them helpful in the past, and they
manufacture.
For liquid ring pumps, you could google Nash Kinema.
In light of our correspondence to date, I would advise against you
"designing" an ejector at this stage. I suggest you buy this one
(ejector,
vacuum pump or whatever) based on a performance spec, see how it
works, and
think about designing the next one.
You may wish to read the article "Selecting Vacuum Systems" in
Chemical
Engineering magazine (McGraw Hill) Dec 14 1981.
Thats it for me on this topic.
Good luck
Steve McKenzie
-----Original Message-----
From: Shah Muhammad Tanweer [mailto:smt_pk@yahoo.com]
Sent: Thursday, October 23, 2003 8:31 PM
To: <a href="/group/PipingDesign/post?postID=laTh_c1oO8Da10gwW4EUH_SJBiCFfKqFFfKUyto6gRWDpf_RxtUGEjGdjFFZQ-OPn6s5XwhrMrrqJ4IfLMonsIJ4VB1vkLo">PipingDesign@yahoogroups.com</a>
Subject: [PipingDesign] RE: Water Jet Ejectors
Dear
Steve McKenzie
I remain thankful for your help. Can you guide me
about the sizes if the water consumption is round
about 1300 gpm. At example 5 and table 8 KARASSIK
chapter 4, does not deel with high flow.
Also please let me know What "SIZE" exactly mean. I
mean what portion of ejector exactly
Ever Yours
Shah M. Tanweer
carefully-considered calulation or any combination of the above. The
intent
is to spark discussion and encourage knowledge-sharing amongst
professionals. If you blow yourself up by doing stuff remotely
described by
info gleaned from reading this list, you are an idiot.
Your use of Yahoo! Groups is subject to
<a href="http://docs.yahoo.com/info/terms/">http://docs.yahoo.com/info/terms/</a>
Your use of Yahoo! Groups is subject to
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Your use of Yahoo! Groups is subject to <a href="http://docs.yahoo.com/info/terms/">http://docs.yahoo.com/info/terms/</a> Received on Thu Oct 23 05:31:00 2003
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