Leshiy 2 explodes

If question to me I can say that I use ONLY air from the local fire department, from their compressor they use for filling their tanks. Quite seldom I use my own HP compressor, but that is not that cheap Chinise one, but normal Italian's with the filters and so on, I used to bought it for 8'000 euro or something like that.

This is why I buy cheap Chinese guns that are made to work with the cheap Chinese compressors. Whenever I open them up they're spotless inside, so far. I am concerned they might eventually damage my cheap Turkish guns though.
 
I did alot of research when building the plenum for my 50 and the wall thickness to inner diameter ratio of that tank is waaaay too thin for anything in the pcp pressure ranges.
Would the type of material make a difference in what wall thickness is needed? I know in my line of work, alloys and heat treating make a big difference in the properties of the aluminum.
 
Assuming 7075t6
And a quick caliper measurement of tube

Here are the numbers using YIELD STRENGTH. Ultimate tensile of 7075 is 82k (actual burst)

Ed, correct me if I’m too far off here.

Dave

Note: The safety factor is a variable, I only used 3 because it is close to what the design gives us before the tube even yields @ 12,808
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I am no expert on filters, but I own a coltri diving compressor. That one use two tubes, first an empty one, with no filter in it, and then a seccond tube with the filter. When I drain it during filling most of the water comes out of the first empty tube, and very litle in the filter tube. Think the purpose is to avoid the filter tube getting drained in water. So I would believe the best option is to replicate that when attaching one ones owns filter, using a similiar two stage system.
The downside is that it is not that pratical filling guns directly, as the two tubes probably has the same volume as the tube on a gun. I do not fill my guns directly, but instead fill my diving bottle first. When I fill my diving bottle to 300bar, and then fill the guns to max 250, the air will be dryer in the gun, than in the diving bottle, as the pressure actually drops from 300 bar, to 250bar. Think also it helps topping of the diving bottle first. I usually top it off at around 200 bar. Air compressors seperate more water, the higher pressure they work with.
 
I can't see air pressure doing the damage we see in the op's pic. This gun got ran over or something, by a tracked vehicle, or something very heavy fell on it. The second a tiny crack is introduced, all pressure vacates. Go watch any tubing burst from pressure.. it don't look like this.. Very entertaining read tho.

@EDgun Not everyone in the West is as confused as you seem to think we are. I will admit tho, that our media outlets are doing a superb job at exploiting a very small minority in our population.
 
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It's amazing how someone will spend $2K on a nice PCP and fill it with dirty air from a $300 dollar Chinese compressor. I can see doing this in a pinch but not a regular basis. Take care of your air rifles gents.
The compressor itself is not a problem. It is all about the filtration system.
 
I believe in real world testing. Years ago I started making Titanium tubes for PCP's. I sent parts out for destructive testing. I was worried until they sent back the parts. It separated at the end of the thread relief at 17,400 psi. I felt better then.
This is obviously the best way. Test to destruction or the end of your capability. It really is amazing what some alloys will take.

Dave
 
I can't see air pressure doing the damage we see in the op's pic. This gun got ran over or something, by a tracked vehicle, or something very heavy fell on it. The second a tiny crack is introduced, all pressure vacates. Go watch any tubing burst from pressure.. it don't look like this.. Very entertaining read tho.

@EDgun Not everyone in the West is as confused as you seem to think we are. I will admit tho, that our media outlets are doing a superb job at exploiting a very small minority in our population.
You do understand that hydrostatic pressure is completely different than gas pressure.. reason being you cant compress liquid so its relatively safe outside of small pin holes etc.. what comes to gas and catastrophic failure of gas cylinder it really goes off like handgranade.. not movie handgranade but real one without all that fireball.. Very entertaining post tho.
 
You do understand that hydrostatic pressure is completely different than gas pressure.. reason being you cant compress liquid so its relatively safe outside of small pin holes etc.. what comes to gas and catastrophic failure of gas cylinder it really goes off like handgranade.. not movie handgranade but real one without all that fireball.. Very entertaining post tho.
crushed… not poped…most likely in a manic tantrum out of frustration… only pressure that got to this thing was blood pressure.
 
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I did a quick check of mechanical properties of various aluminum alloys. The yield strength varies between 3.5 MPa (1100, no temper) to at least 70 MPa (7075 T6) . To me that makes simple measurements of aluminum components not very valuable without knowing the alloy used. I would expect an airgun to be closer to 7075 or possibly even 7075 (2024 seems to be another possibility, its around 40 MPa depending on temper). I doubt the tubes of inexpensive moisture filters are this kind of aluminum, however. They could be recycled material which could be anything from really strong to something like 1100. I don't know of any simple way to tell unless the manufacturer tells us. An airtube made of 1100 could be equally safe as 7075 but it would have to be about 20 times as thick.