Fill lines, pressure ratings, typical failure pressure over short periods of time

[delooper]

Hi all,

Once I was filling my SCBA bottle (unsupervised) and forgot to check up on it. The pump appears to have got the bottle up to about 340 bar, and the fill line burst.

This has got me wondering, what is the landscape out there for PCP fill lines like?

I don't know who really makes them vs. the people that just relable them and sell them all over the place. Also, is there much variability for pressure rating, and do any of you know when these lines will burst, when taken over their pressure rating for a short period of time?

My line burst at the junction between the metal and ?plastic? that the line was made out of, so it wasn't either material that really failed, it was the mating point. So I imagine manufacturers that get the mate-up better would have the higher fill ratings.

That said, I'm totally fine if my lines fail at 340 bar -- I'd rather the line fail, than the pump or the bottle.

 

[Motorhead]

Generally "MOST" quality HPA hoses that service rate at 300 bar will test @ 500 bar, so one would NOT expect a failure to happen.

Now Co2 rated hose ( Which are very common coming from the ranks of Paintball ) many times are service rated far lower in the @ 150-200 bar range and test @ give or take 300 bar. If this rated hose gets subjected to 340 bar ... Yea it may very well rupture, as would similar rated fittings & fosters etc ...

 

[delooper]

It's a bit of a shame, I lost track of who I got that fill line from. And I chucked it so I can't look up the markings.

 

[willy]

Sometimes when a tank falls over with the connection hooked up to it?it will kink the hose at that point and weaken it"

 

[Scotty1]

The burst pressure on my Airtanks Plus fill lines is something like 21000 psi, the connections are typically the weak link.

 

[JimD]

My fill set is from Airtanks Plus so I am pretty sure my weak link is the 36 inch extension hose I purchased from Amazon. It's rated to handle 4500 psi air but I would be surprised if it could take 10000. The outside is woven stainless steel, however, which could help contain fragments it if ever fails. Not sure what the short hose coming out of the YH can take either. I stay close when filling the tank but don't stand right next to the compressor except when I need to do something. The only thing that has ever failed is the O-rings in my moisture filters.

 

[delooper]

I've had two hose failures, in each case it was a little "bubble" leak, where the hose meets the metal fittings. They were very slow, non-violent failures, with the line losing relatively little pressure -- when I came into the room after the failure the pressure in the line was over 340 bar.