TargetTalk

1) I got a carbon fiber tank from one of my friends who is a fire fighter. It doesn't have a k-valve on it so I have no idea what I would need in order to make this work for my pcp's. If I got a k valve, could I install it myself?

2) If I got this http://www.champchoice.com/detail.php?item=56515000 would it work? And could I install it myself?

3) If this tank is 4500 PSI, would a scuba place be able to fill it?

Thanks for the help.

You are better off getting the k valve. This is something you can not do yourself and this should be done by a scuba place. Yes your tank will be able to be filled to 4500 psi, but the k valve will only let out 3000 psi by design. So that would work well for you then because you would get more fills and keep it at the 3000 psi mark on your cylenders longer. Get the K valve and have a scupa place do the work for you, it shouldnt be to much money to have it filled.


lax

Apparently, a k valve cannot go on this tank. K valves can only accommodate 3000psi, this thing is 4500psi. I think I need an adapter. I have this thing that came with it The silver thing on the right goes into the bottle and the thing on the left can attach to a hose or some quick release kinda thing Does this info help? Can I still use this tank?

A k valve is made to only let out 3,000 psi, it can hold your 4500psi tank. And if you really wanted to you could just tell them to only fill it to 3000, but you should be able to go to 4500 psi with it.


lax

Just to start as a European - 1 bar = 15 psi so i will interchangeably use 200/232 bar = 3000psi, 300 bar = 4500 psi.

It looks to me that the brass thing is a regulator which controls the outlet pressure. The first (inlet) pressure gauge measures up to 4500PSI but that doesn't mean that the cylinder supports that, it has a standard 232 bar fill in it at the moment. The second (outlet) pressure gauge is measured in PSI and looks like a likely output pressure is about 200 - thats 14 bar which is a realistic pressure that you would input into the demand valve on a firefighting BA mask. So that device is going to be of little use to you to refill your cylinders - 14 bar aint gonna make it!!

You will need a new valve, because you cant fit anything standard to what you have and if you are going to use 300bar gas you need the right fittings! Get something like you linked to before and get a scuba shop to fit it. But check with them first that it will fit - carbon bottles can be peculiar in the fittings that they use.

When I say 'like' - the valve you linked to is a 200 bar fitting and wont allow you to make use of a 300 bar bottle. The 200 and 300 bar DIN fittings have different numbers of threads so you cant fit a 300 bar filling whip into a 200 bar valve. The main reason behind this is to ensure you cant fit a 200 bar regulator on a 300 bar bottle, and have it explode on you.

Have a quick look here for the sort of things you can get. This works on a standard DIN valve, which the scuba shop wont have any issues with sorting out!

http://www.wighillparkguns.co.uk/produc ... ?prod=1900

Also check that it really is a 4500psi bottle, its not guaranteed (although the majority certainly are). The scuba shop can confirm that.

HTH

regds


Ed

These links in UK should point you in the right direction:

http://www.undersea.uk.com/catalogue/catalogue.pdf

http://subaqua-products.co.uk/

very handy source for all oddball metric - imperial problems.

A k valve is made to only let out 3,000 psi, it can hold your 4500psi tank. And if you really wanted to you could just tell them to only fill it to 3000, but you should be able to go to 4500 psi with it.

This is WRONG. a K valve is designed to handle ONLY 3000 psi pressure, not to act as a reducing vavle to drop pressure from a higher amount to 3000.

To the first poster, you got a free tank from the fire department because it is no longer considered safe for use after a certain period of time, and it cannot be hydrostated like traditional solid metal tanks. Personally I would not use it all, but thats me, I like living and I like having all my fingers and toes.

IF I decided to use it anyway, I would consider putting a low pressure in it, say 2000 psi, which is enough to shoot a 60 shot match in most CA guns I am familar with

[/quote]

To the first poster, you got a free tank from the fire department because it is no longer considered safe for use after a certain period of time, and it cannot be hydrostated like traditional solid metal tanks. Personally I would not use it all, but thats me, I like living and I like having all my fingers and toes.

[/quote]

Thanks for all the help from everyone. Definitely an experience, but with all this trouble, I think I should just buy a new tank with all the right fittings on it.

This tank is rated good for 10 years. It was manufactured in 8/2007. So, it's safe to use. Assuming that it is safe to use, would I need a regulator in addition to the valve that is already on the tank? Or would I simply need an adapter from the outlet it has to the 200DIN adapter?

I didnt realise a 'K' valve was a standard on/off valve else I would have also discussed that.

Our mod is absolutely right you cant use a 200 bar valve in a 300 bar cylinder otherwise it will go pop. However 'pop' as in a total stored energy of something like (i believe) 300,000 ft lbs... the good news is if you take it to a scuba shop they will

a) check the cylinder rating and if it is in test
b) if its in test, sort you out with a suitable valve for the cylinder
c) explain what you can connect or not
d) laugh at you and call you an idiot if you suggest something that will result in you blowing yourself up
e) chop up your cylinder for you if it is out of test and cannot be put back in test.

At least, that's what would happen over here

regds

Ed

to fstrnr:

You know, a new tank, that is hydro'd & filled will only cost you a few hundred dollars.

If you do something that compromises the integrity of that carbon tank .... really, you can lose your life.

Go and look at what they do to hydro test a tank .... even then it's in a big water filled tank ... they do all this for safety.
http://www.osha.gov/SLTC/etools/evacuat ... hydro.html

Recommendation: Completely empty the tank.... double & triple check it and then have someone qualified destroy it.

If it was manufactured Aug 2007 it should still be fine, just get someone qualified to give it a visual inspection. There's no point not using it if its fine, just get the right valves on it !

Ed

These sites have the info and parts that you need. Please have the person who fills the tank, inspect the tank for your safety. Seems shady that a fireman would give away a good new tank.

http://www.airhog.com/

http://www.hamcontact.com/airgun/HoseAssembly/

http://www.network54.com/Forum/79574/me ... eplacments


Ter

Sorry guys i made a mistake i was thinking of something else at that time.


lax

Fstrnr
Sorry to assume your tank was a discard. In my defense, we get questions at least once a month about people trying to use the fire department rejects.

Regarding acquiring interfacing adapters, High Pressure fittings are intentionally designed to prohibit mixing of pressures and gases. If you try to do this on your own, you will have to custom make the fittings yourself, or find a machinist who trusts you, as most shops will refuse to violate safety designs on liability reasons.

A good source for overall information is here
http://www.pilkguns.com/scubasafety.shtml

Anonymous wrote:These sites have the info and parts that you need. Please have the person who fills the tank, inspect the tank for your safety. Seems shady that a fireman would give away a good new tank.

http://www.airhog.com/

http://www.hamcontact.com/airgun/HoseAssembly/

http://www.network54.com/Forum/79574/me ... eplacments


Ter

Shady? He's my friend

Anonymous wrote:<snip> Seems shady that a fireman would give away a good new tank.

Ter

Does it not seem even more 'shady' that a fireman, someone who's job it is to save lives, would give away a knowingly faulty item ?

These people regularly replace perfectly good items for something that may be better, or lighter or just as a routine '3 year renewal cycle'.

Rob.

Thanks Rob

Some friendly advice, give that back to the firey you got it from and go buy an approved cylinder with a DIN valve. Ask QANTAS what can happen when a valve lets go on a cylinder, they have a M$10 repair bill and could have lost a 747. The message, don't stuff around!

After clearing the baggage and cargo from the forward aircraft hold, it was evident that one passenger oxygen cylinder (number-4 from a bank of seven cylinders along the right side of the cargo hold) had sustained a sudden failure and forceful discharge of its pressurised contents into the aircraft hold, rupturing the fuselage in the vicinity of the wing-fuselage leading edge fairing. The cylinder had been propelled upward by the force of the discharge, puncturing the cabin floor and entering the cabin adjacent to the second main cabin door. The cylinder had subsequently impacted the door frame, door handle and overhead panelling, before falling to the cabin floor and exiting the aircraft through the ruptured fuselage.[/url]