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mike4
02-17-2013, 09:39 PM
the post on cutting gas struts reminded me of a small problem that I would like to solve for a client , they have a LNG tank which supplies their factory , however there was no provision for a sample line to check the composition of the contents , (something to do with pollution rules), and so far no-one has been able to come up with a small high pressure shut off valve suitable for high pressure gas.
The smallest that I have found commercially is 2 inch or 50mm .

We need 1/2 " or 13mm.With a working pressure of 2-5 thousand PSI for safety .

Cost is also a factor , I got a quote of $1800 for a one off purchase for a 25mm unit .

Any ideas ????
Michael

Guido
02-17-2013, 10:12 PM
http://www.hvacpartsoutlet.com/refrigerant-line-tap-valve-1/4-22--5/16-22--3/8-22.aspx

Refrigeration tapping valve.

If you're messing with LnG at 2-5000 psi, while someone balks at spending 1,800 bucks, and some twit authority is requesting a sample for polution monitoring--------there are better people/jobs to be found elsewhere.

--G

RussZHC
02-17-2013, 10:18 PM
www.sherwoodvalve.com/assets/.../430SeriesValveCutsheet5-11-10.p...

not sure that is the type of valve you are after (specs look OK though...)

Edit: link does not seem to work (its for a pdf file) I googled "high pressure gas shut off valve" and it was the fifth one found

mike4
02-18-2013, 12:21 AM
The pressures mentioned are for our safety , the line runs at up to 900-1000 , I tend to err on the side of caution with flammable gas/liquids.
The tap mentioned in the link are good but the body is cast aluminium or somilar and at those pressures I would not be confident in using one of these , they are what I attempted to describe in the post about gutting gas struts.

I will have to make a similar decice out of steel but it does not solve the issue of the valve as I cannot have a 40 tonne tank of gas with a screw on cap to hold pressure in .

Thanks for the link however.
Michael

mike4
02-18-2013, 12:26 AM
http://www.hvacpartsoutlet.com/refrigerant-line-tap-valve-1/4-22--5/16-22--3/8-22.aspx

Refrigeration tapping valve.

If you're messing with LnG at 2-5000 psi, while someone balks at spending 1,800 bucks, and some twit authority is requesting a sample for polution monitoring--------there are better people/jobs to be found elsewhere.

--G

Guido , I am trying to solve a problem for someone who sends a lot of work my way and has been a customer for a couple of decades.
The $1800-00 valve was way too big for the situation we only want a sample not run a small furnace.

I didnt write the pollution rules , just some shiny a*^e in an office trying to justify their job.
Michael

macona
02-18-2013, 12:26 AM
Swedgelok and whitey have valves that go that high, easily.

mike4
02-18-2013, 12:28 AM
macona , thanks I'll give them a try.
Michael

Black_Moons
02-18-2013, 06:48 AM
Hmmm, Maybe look into Scuba/CO2/paintball (refilling?) equipment?
Anything CO2 is going to be rated 1500psi nominal at least, likey 3000 burst.

Scuba and air powered paintball/pistols run 3000~psi nominal, although I guess you probley want something 'gas rated' to prevent chemical attacks, although if you can get a datasheet on what the seals are, you could look up its compatability yourself.

Hydraulic stuff might also be an option, as they would be rated 2,000psi+

In a previous job, I had seen a water meter used to measure liquid propane!

J. R. Williams
02-18-2013, 11:20 AM
Does the valve have to handle LNG or later down stream where the product is a gas? If it is LNG then a valved suitable for the cryogenic service will be required. Why sample at the liquid position?

Paul Alciatore
02-18-2013, 12:57 PM
I have seen many plants that had provision to fill the small tanks from their very large LNG tanks. Why not install such a station and you can use a small tank to draw samples. You would not have to fill the tank each time, just enough to sample it. It may be helpful for other purposes too.

Or perhaps such a station would also cost too much. I do not know the cost but I would look into it as a possible option.

Do check with the gas supplier and perhaps their competition. They must have some suggestions or options.

dave5605
02-18-2013, 04:41 PM
Is this the kind of valve you are looking for?

http://www.triadprocess.com/adwordsB.cfm?searchTerm=High%20Pressure%20Valves&gclid=CPLfr7vowLUCFQmxnQodISUA0w

J. R. Williams
02-18-2013, 05:13 PM
Typically a sample of a gas is drawn off into a small evacuated sample cylinder, commonly called a sample bomb only in the gaseous form, not liquid.

Guido
03-13-2013, 11:44 PM
ttt Any luck???????

mike4
03-14-2013, 04:08 AM
Guido,
Yes I managed to get hold of several Swagelock valves , stainless to boot , so being outside wont be a problem .
Now have to make some time to get the job done .
Michael