Copper DWV fittings

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theBOOM
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Sat Jun 19, 2010 9:50 pm

I seem to have bought a copper dwv female adapter (1/2") by accident and now I'm wondering how unsafe it is to use it at high pressures, it has about 1/4" of less depth for the pipe to slide in, which leads me to believe it is DWV.

Also, if I reheat a soldered joint and remove the fitting can it be reused or will it be unsafe to use it on another project?

Thanks.
evanmcorleytv
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Sat Jun 19, 2010 10:56 pm

Copper dwv, like all dwv would be fine to a certain degree... I think it would be ok, but how thin is the actual peice? :D :) :o
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STHORNE
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Sat Jun 19, 2010 11:27 pm

Never trust dwv on pneumatics.

On low-tech combustions, yes they are OK. But when you start dealing with real high pressures, dwv is not your friend.
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Technician1002
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Sat Jun 19, 2010 11:49 pm

If unsure, hydrostatic test. My DWV cannon passed the test and is now in it's 8th year of service. It passed a 100PSI 30 minute test with no issues this year.

I didn't bother to fill it with water this year. I just hooked up the compressor and let er rip. Then I did a 100 PSI test shot. Projectile launched into a washing machine, through the side.
It normally operates in the 40-75 PSI range.

DWV cannon is the one under test on the right.

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theBOOM
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Sun Jun 20, 2010 1:54 am

It's copper not PVC, the fitting is not thin, it simply has less socket depth. I was just wondering if anyone had experienced these fittings, o well I'll go buy the fitting again and return this one.
evanmcorleytv
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Sun Jun 20, 2010 8:51 am

yeah, that seems like the best choice :? but, I really look forward to seeing your new cannon! :D :D :D
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Crna Legija
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Sun Jun 20, 2010 9:18 am

how high pressure you talking about. it should hold 300psi no problems.
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Biopyro
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Sun Jun 20, 2010 2:00 pm

All copper is DWV, certainly in the UK anyway. You will be absolutely fine.
http://www.engineeringtoolbox.com/coppe ... -d_20.html
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theBOOM
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Sun Jun 20, 2010 4:53 pm

Um I was intending to use it at 400 psi or so, its for a small coaxial gun.
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SpudFarm
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Sun Jun 20, 2010 4:59 pm

theBOOM wrote:Um I was intending to use it at 400 psi or so, its for a small coaxial gun.
I would go for it. Solder joints is extremely strong if done right.
Last edited by SpudFarm on Sun Jun 20, 2010 5:08 pm, edited 1 time in total.
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c11man
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Sun Jun 20, 2010 5:00 pm

copper is normaly not dwv in the us, i have only seen dwv in 1.5 and 2inch but i guess it comes in smaller too...
and returning would be what i recomend
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Technician1002
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Sun Jun 20, 2010 7:57 pm

The copper they use for Air Conditioning is a bit pricey, but it is never low pressure. They mark it by the true OD instead of the nominal ID. For this reason a 5/8th inch pipe will fit a 1/2 inch plumbing fitting. Be sure to order the right size.

More info on this stuff is here;
http://www.plumbingsupply.com/coppertubing.html
Question
I have 'refrigeration grade' copper tubing. How do I determine which size copper sweat fittings to use?"
Answer
Refrigeration grade copper tubing is sized according to the outside diameter of the copper pipe. The plumbing industry uses the inside diameter (nominal) size of the pipe for their measurement of sweat fittings. To figure what size sweat fittings to use on refrigeration grade tubing you must subtract 1/8" from the outside diameter of the pipe measurements. If you have 1/4" outside diameter refrigeration grade tubing then you will need to order 1/8" (nominal) sweat fittings. Click here to see our conversion table.
I used to do some commercial refrigeration in my past.
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