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High pressure flex hose failure videos?

High pressure flex hose failure videos?

High pressure flex hose failure videos?

(OP)
I have been hired to do some safety engineering work. In my exploration of the work site I have found numerous high pressure (up to 6000 psig) flex hoses without restraints.  These are high quality stainless convoluted or stainless/PTFE hose, but many are decades old. They receive a visual inspection yearly but that doesn't mean much to me. My experience is that these inspections are pencil whipped.

I have suggested they immediately implement a requirement to install restraints on hoses being used at 150 psig or more. (This is the industry standard.) It has been met with a little resistance by those resistant to any changes.  So I need to prove to these guys how serious this isse
can be.  

I know I've seen an old video from the '60s where a high pressure stainless hose about 20' long fails and proceeds to destroy absolutely everything around it, including smashing cinder block walls. All the videos I can find on the Internet show hydrostatic failures, pull test failures, restraints actually working, or the gas being shut off immediately after failure (which wouldn't happen in a real failure.)

Has anyone else seen this video or know where I
might be able to get it?  Or something similar?  Thanks!!    

RE: High pressure flex hose failure videos?

What is the fluid?
What is the industry standard to which you refer?

Ted

RE: High pressure flex hose failure videos?

6000 psi of ANYTHING will take off your finger, hand, or head!!!

I do know the Navy has some strict standards working with their steam systems - maybe you can find something there... Just a thought.

OR call a MFG of 6,000 psi hoses - pick up the the that heavy phone and call...

RE: High pressure flex hose failure videos?

I saw 200 psi steam in 20' of 2"  high quality stainless convoluted hose break free and wrap itself around another pipe (like swinging a key chain around a finger).  Sorry, no video.  Took about 4-5 seconds.  It would have killed someone - had they been there.  Luckily, they weren't!

Good luck,
Latexman

RE: High pressure flex hose failure videos?

Braided wire over-wrapped hose is highly unlikely to become completely severed if it fails. It is made from multiple wires that will not fail simultaneously. What is an anti-whip device but another wire? I a hose assembly is capable of catastrophically failing and injuring someone then take appropriate precautions, but don't go overboard.

RE: High pressure flex hose failure videos?

The range safety document EWR 127-1 I'm sure has a requirement for restraints, though it's been 15 years since I worked with it so I'm not sure where it might be.
http://snebulos.mit.edu/projects/reference/NASA-Generic/EWR/EWR-127-1.html

Now I work in the industrial gas industry, and the same 'industry standard' applies, but I can't say where it might be written. If I look at any hoses over about 100 psi, I would expect to find hose restraints on either end. You might try CGA codes. I think you're right in insisting on the hose restraints. That situation would scare me too.
 

RE: High pressure flex hose failure videos?

The braid is the restraint.  That is about its only purpose (other than looking pretty.)  If extra strength is needed, braids can be doubled, etc.

The key is in how the braid is welded to the corrugated section of the hose.  It all gets back to the adage that 'a chain is only as strong as its weakest link.'

Maybe you should review your hose specs for the applications in question.  We regularly use them in applications in the multiple of thousands of PSI without any other restraint than the braid.

rmw

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