At the board's suggestion I replaced the "PVC" plumbing in my garage with "Galvanized". This stuff was a lot more expensive and harder to install than the plastic. The plastic went up in less than two hour's and cost's less than $30. The metal pipe took nearly three day's to install and after buying all the adapter's needed cost almost $200.00. It may be safer as you guy's say, but if I had to do it over again I'd stick with the plastic. I already know that I'm gonna catch hell for this. Also I guess I do feel a bit safer, but GEEZ.

 

...As the old greybeard once said when I was comtemplating cutting some corners on safety to save a few bucks..."How much ya will'n ta pay fer piece O mind...?"

 

Coudn't you re-use the adaptors etc from the PVC installation??? The pipe and main fittings are reasonably priced. It does take longer than cut-glue but it is stronger and is safe.

Even so, $200 is cheap compared to a lawsuit when you kill a neighbor or his kid. Or a funeral for you or yours...

Plastic is a major NONO!

 

The adapter's used on the plastic were plastic also, and I just figured that if plastic was unsafe get rid of all of it.

 

Yeowch, you were right to get rid of the little plastic adaptors. Those were an accident waiting to happen too. I just use metal for all my stuff. The only place I run plastic is DWV lines and the risers to the sink and stool.

 

.
* PVC Piping and 2 hours installation time. Twenty Dollars.

* Metal Piping and 3 days installation time. Two hundred dollars.

* Reducing the chance to maim or kill yourself. Priceless.
.


I for one applaud you for switching over to metal piping! Sure it cost more and took more time to install. But aren't all good things in life worth more time, money and effort?

-Ron

 

big1,
All the extra time, work and money is tough to handle. But isn't the fact that you're here to gripe about it NICE? At least we will still be able to read your comments for a long time to come.

 

We ran the 2 bays we added with 1/2 and 3/4 copper line. It was relatively easy to fit and inexpensive. Water pressure runs around 125 PSI around here and copper holds up for MANY years so we felt safe using it for air.

JohnF

 

Water pressure and air pressure are entirely different things... That is how some of the guys got into trouble in the first place by assuming that since PVC would hold water pressure that it would work for air also. Copper being a metal will not fail like PVC does so it supposedly works... I have not seen any regulatory info to date that shows it will not.

 

Copper is fine for pneumatic lines. If you ever seen the climate control systems in a building, all air lines are copper. I have seen some pneumatic piping in a building at work that was installed in 1921 and is still fine today. They used flare tubing or the more rigid pipe.
Hope this helps.

Dan 69 F-100 302, C4
On order... 2003 Ranger EDGE

 

Yesterday at work we were testing out a new 50 ton hydraulic ram. Having a great time bending I-beam. I had the internal pressure up to about 11,000# when the fitting at the gauge came loose from the stainless tubing. Tubing popped off and squirted out a bit of fluid. I was thinking about the PVC threads after that and if it had been air pressure, I probably wouldn't be here now.

 

when you consider the cost...remember the old motorcycle adage

"if your head is worth ten bucks, buy a ten dollar helmet !"

john

 

Eric is 100% right, air and water are completely different. You guys better get a coffee, class is in session.

Picture 1 cubic foot of air in front of you,(12"X12"X12" cube). Now lets say it is at the same pressure as the air in the room,(atmospheric). The pressure would be 0 bar on a gage. Now put your hands on the sides and squeeze it until the pressure is 15psig, or 1 bar. The size of the cube is now exactly half of it's original size, (6"X12"X12").

Now instead of squeezing, you are to add or pump more air until the pressure is at 15psig or 1 bar. The cube did not get any bigger, but the VOLUME of air inside is now doubled. If you were to raise the pressure to 30psig, or 2bar, the volume of air inside the cube would be tripled.

Take that same cube and fill it with water. If you were to try to add more water to increase the pressure, the cube would NOT take the water without being allowed to grow in size. Water is NOT compressible.

Now lets take that plastic piping system and bring the pressure up to 175 psig. That's 11.6 bar, or 11.6 times as much air in the pipe, as what would be in there at room pressure.(atmospheric) If a small crack begins to form in the pipe, the air inside would want to release it's energy thru that crack, and the VOLUME of air exiting the crack would be so great(the VOLUME, not the PRESSURE), it would break off more and more of the crack, until it literally explodes into the surrounding room, which is at 0 bar and offers no resistance to the expanding air from the pipe.

Now if that same exact pipe were filled with water and pumped up to 175psig, and a crack were to happen, the water would only spray out into the room for a fraction of a second because it has NO stored energy or volume to release, yes, it was at a high pressure, but it's volume is still the same as it was with 0psig pressure.

PVC manufactures' specs say 'Not for air distribution' and OSHA and PPI say NO air in pvc pipe. They don't say that because they are bags of wind, they says that because people have, and will continue to be injured by misuse of these products.

Take a 1 foot piece of pvc, copper and steel pipe and put them all in the freezer for and hour. 1 by 1, take them out and slam them on the ground, starting with the piece of steel, then the copper, then the pvc. The steel and copper pipe will dent up, but the pvc will shatter. (Pick up those pieces of plastic and picture them flying at your head at 400mph, are you fast enough to duck?) The reason for the freezer is to simulate the temperature of the pipe when it has air moving thru it. Ever notice how a blowgun gets cold in your hand after using it for a while?

Now there ARE products specifically meant for air such as Duraflex@ plastic pipe. This IS designed for air or gas under pressure and would be safe to use. This does not use glue fittings,(not last time I checked anyway), it uses mechanical terminations that get crimped down with a special tool. Wouldn't be worth the expense unless you were running hundreds of feet of the stuff.

I hope some of this stuff helps some of you understand these things, and the consequences of misusing a product for other than it's intended purpose.

If not, then it's just typing practice for me.

 

The plastic piping that I HAD in my garage was rated at over 700psi that's why I couldn't understand all the fuss. I do understand the concept of safty and so after reading the information on this board I eleminated it. To me pressure is pressure.

 

As I said b4: Water pressure and air pressure are entirely different things...

A liguid under pressure will expand very little (<1%) when the pressure is released, a gas will of course expand violently and expand according to it's relative pressure.

The PVC fails in a brittle mode like ice, glass, or a ceramic. Metal usually fails in a ductile mode, bending and deforming (except hardened steels and alloys etc).

Under pressure if the PVC is struck a blow, bent or twisted, vibrated, or degrades due to chemical, oil, solvents, or UV attack it will shatter and throw shards many feet, right thru somebody...