Lightweight cylinder HW 100 carbine recommendation

[Goatofmendez]

Dear Goat

I have contacted the manufacturer for specification clarity.

Your figures state a wall thickness of 3.5mm in fact it is 4.3mm wall
Material tensile strength is 245 Minimum MPa
Using Barlow Formula you can see a 650 bar without deformation is easily achieved. We did not test to destruction as 650 bar is over double that the tube is rated at. Hope this helps allay any concerns . Any questions get back to me and i can contact the manufacturer further for you.

If the tube that we are talking about is indeed one of ours as this is all hear say though general conciseness and feel from this thread is that it is. How the tube split? is a good question!

Regarding your comment on the test house results.Why would we question a expert in there field in their test results? Who provided full certification? We are not experts in this field are you?

Hi thanks for the reply.

You quote a wall thickness of 4.3mm @ a tensile strength of 245MPa. With these figures I get the deformation pressure as 569.5bar. While I completely concede that this is more than double the working pressure for normal operation, my problem is that on your listings you mention "Rigorously tested & certified to 650 bar with Rapid evacuation and rapid refill in a 10 times cycle, with no deformation or loss of structural strength recorded." This statement flies directly in the face of the 569.5bar deformation pressure calculation using Barlows formula. As scientifically it will deform at 569.5bar.

The answer your question "Why would we question a expert in there field in their test results?" Well, perhaps the fact that one of the cylinders split from end to end at 150bar? I would certainly be questioning them on both counts. You don't need to be an expert to reaslise that there is something wrong when tubes tested to 650bar are splitting at 150bar, do you?

regards
Goat