2 questions

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
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MrCrowley
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theepicmool wrote:1. The wiki article for fittings says you can tell if they are pressure rated by how they look etc. To what extent (in PSI) does this mean they are rated?
Next time I'd appreciate it if you decide to read the full article.

Not only is there a huge, cannot be missed, link that directs you to a chart directly telling you the rating:
http://www.pvcplus.com/PVC%20schedule_40_&_80_pipe.htm

But there is also half the damn page telling you how to identify the pressure rating by what is WRITTEN ON THE PIPE:
Identifying Pressure Rated PVC By Text
Common Misconception: Sch 40 written on the fitting/pipe does not mean the fitting/pipe is pressure rated, the 'Sch' system is a thickness rating, not a pressure rating. You need to look for NSF-PW.

Tip: On a Pressure Rated fitting, the writing is usually raised and can be read once painted over. In the case of pipe, if enough layers of paint are on the pipe, you probably can't read the print, so make sure to write down what the pipe has written on it before you paint over it.

Note: The above is intended for identifying American fittings and pipe. To identify Australia/New Zealand fittings, see below.




Fittings:

To find out if a fitting is pressure rated, it should have 'NSF-PW' written in raised text, it may also have Sch 40 (or 80,120 etc) on it. Most American fittings don't have a pressure rating on them, but if they have NSF-PW ("PW" stands for Potable Water, which, by nature is under pressure), you're okay, it will be pressure rated.

Pipe:

For pressure rated pipe, it should have written on the side: 'NSF-PW Sch 40 (or 80,120, etc) XXXPSI @73F'

XXXPSI, is the pressure rating, it changes depending on the 'schedule' rating and the diameter of the pipe. The pipe may also have a different temperature rating, but the most common say '@73F'.

The pipe may also have 'DWV" written on it, as long as the pipe has a pressure rating, e.g '300PSI @73F' you're okay.

If it doesn't have 'NSF-PW' or pressure rating, chances are it's DWV.


You can also identify Pressure Rated or DWV fittings and pipe by their 'AS' number written on them, but it's not essential to learn. More details about 'AS' numbers coming soon.




Identifying Australian/NZ Pressure Rated PVC fittings:

Since Aus/NZ use a different measuring system, PVC fittings and pipe have a different way of identifying if they are Pressure Rated or not.


Fittings:

To find out if a PVC fitting is Pressure Rated or not, it should have written on it in either raised or plain text, either:

Class X (The class ranges from A-F, with F being the most pressure rated, usually Class 'C' is a minimum in a pneumatic.)
PN XX (The PN (Pressure Number) system has ratings ranging from 0-22+. PN 10, 12 or 18 are the most common and PN 10 should be the lowest rated fitting you should use in a pneumatic.)
It's that simple. To find the pressure rating in PSI, multiply the PN number by 14.5. E.g PN18 x 14.5PSI = 261PSI. The PN number is in BAR, to find it in Kpa, multiply the PN number by 100. E.g PN18 x 100 = 1800Kpa.

Pipe:

To find the pressure rating of PVC pipe, use the same system as you did with the fittings. Find the PN or Class number. Try not to get confused with the 'DN' number, which is the nominal diameter in millimetres. E.g DN50 = Diameter 50mm.

As with the American system, there is another way to determine the pressure rating, and that is by AS/NZS number. More information to come soon.

European Pressure Rating System: In Europe the EN 1452-2 norm is used to classify pressure rated pipes, and they are identified with a PN (pressure number) code, which stands for the allowable pressure in Bar. The most common ratings are PN10 for pipes and PN16 for fittings, corresponding to 10 Bar (145 Psi) and 16 Bar (230 Psi), but up to PN25 is available.

Retrieved from "http://www.spudfiles.com/spud_wiki/inde ... _Rated_PVC"

Sure, you may think i'm being a bit mean, but when the answer is right in your face and you chose to ignore it, it makes me feel like I wrote that whole bloody thing for nothing.
theepicmool
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Triggered bust disks? Like using a ball valve, then a bust disk so it wont fire randomly? Probably also cheaper then a sprinkler valve too. I'm not fond of the ridiculous reload time though.
theepicmool
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@MrCrowly Actually, see my Canadian pipe post. There is no NSF (NATIONAL Science Foundation) rating on pipe here, its all CSA (CANADIAN standards Association) ratings.
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MrCrowley
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Then what else is written on the pipe? I asked in your last topic also.
theepicmool
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Ill have the writing tomorrow, I'm going to the store then.
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I live in Canada and all my pipe has NSF written on it :roll: .
"If at first you dont succeed, then skydiving is not for you" - Darwin Awards
theepicmool
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Where did you get it? Home Hardware keeps trying to sell me CSA pipe when i ask for pressure rated.
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Ok, I checked the pipe I have lying around, and it has both the CSA and NSF ratings on it. It hardly matters because it tells you the exact rated pressure in PSI, so just look for that.
"If at first you dont succeed, then skydiving is not for you" - Darwin Awards
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