What thread is in the top of a fire extinguisher bottle?

[Steve_GQ]

I'm planning on using a 9L water fire extiguisher bottle for an air tank/resevoir for my on board ac compressor. Does anyone know the thread size and type so i can source the fittings i need. I'd measure it myself but i don't get the bottles till next week.

thanks steve

[phippsy]

When I did this to one, I pulled the handle and all the bits out of the top fitting, plugged all but one of the holes with bolts, I think they were m8 or smaller then used a quick fit fitting and some nylon hose which we had plenty of at work to join into the rest of the line.

edit. I'll try to get a picture tonight if it helps.

[Eddy]

Shoulda asked yesterday cleaned and recharged mine then.

[Thommo 73]

most valve joints have weld in "sockets" (tube with thread in it),
what i used for mine.

[r0ck_m0nkey]

You'll have to get the extinguisher first, then figure out the thread type and size. It differs between brands, age and everything else, there is no one size.

[Tomo_89]

i did this a while back.. to start with pull the trigger/handle set up off so that you just have the tank with the brass fitting in the end. pull out the brass bit and you can remove the internal pickup inside the tank as you don't need this for an airtank. while you have the brass peice off take it to a hydraulics shop and get a quater inch hose fitting that will thread into the place where the old hose came out of and get a relief valve that will go into the pressure gauge fitting. then tap a tread into the hole in the top where the plunger went through and plug it with a bolt.

hope this helps

Thomas

[mule75]

most fittings that need the threads to seal are BSP threads which are plumbing threads. you should be able to get what you need from reece/tradelink.

[Steve_GQ]

thanks guys