Why NOT to use elCheapo Cast Fittings

[kennyd]

So tonight I was reconfiguring my air lines in the basement to add a valve for the new line that will go out to the pole barn, got it all together and heard a leak...so I soaped up all the joints expecting to find one that I did not tighten enough. Well, to my surprise, it was actually the Tee that I installed leaking, but NOT from the threads, but the body itself. This was a brand new 3/4" Tee from Lowe's, made in China of course! This leak occurred at 150 PSI, heaven only know what would have or could have happened at 2500 PSI!BOOM?

I know many will say "I have had them on my machine for 20 years without problems". Well you are lucky and those old fittings where probably made of real metal and in the USA.

Original setup feeding the copper lines ran through my basement and garage:

The leaking Tee:

The new setup (still with leaking Tee though):

 

[radioman]

scary! work looks good though.

 

[AKKAMAAN]

So tonight I was reconfiguring my air lines in the basement to add a valve for the new line that will go out to the pole barn, got it all together and heard a leak...so I soaped up all the joints expecting to find one that I did not tighten enough. Well, to my surprise, it was actually the Tee that I installed leaking, but NOT from the threads, but the body itself. This was a brand new 3/4" Tee from Lowe's, made in China of course! This leak occurred at 150 PSI, heaven only know what would have or could have happened at 2500 PSI!BOOM?

That cast iron Tee is only rated for "low pressure", and I am not surprized that China quality fails.....buy five and one works..

 

[Tig]

In 1990 when I built my house I had a leak at the laundry tub. I was surprised to finr the casting of a shut off valve leaking through a flaw. Not sure where it was made.

 

[J_J]

kennyd,

What is the pressure rating on that flexible pipe in your setup. It looks like a water heater connection hose.

 

[Gary Fowler]

It looks to me like you are pushing the limit on everything you have there. Those malleable iron fittings are max 150 pound rating regardless of where they are made and the valves look to be 150 or less also. Check the stamping on them to see what they are rated for. Most brass 2 piece valves like those are not rated for more than 150 PSI
If you are going to go that much pressure, you should look at forged steel fittings and valves.

 

[ray66v]

Try finding fittings anymore that are not "el cheapo", made in China. Leakers, and bad, or no threads at all, have been par for the course, for a while.

I would also suggest that you do not have a regulator that it is not removable. Like everything else, they do not last very long anymore. And when the diaphragm goes, you either have a very annoying leak, or no air at all, down stream, until you shut down everything, and repair, or replace it.

If you feel a regulator is necessary, you will have more volume by not regulating the pressure, until the point of use. And then, use one with quick disconnects, so in the event of a malfunction, it is removable.

If your going to hard plumb it, you should consider having a few valves to be able to bypass it when, (not if), it fails.

 

[Hooked_on_HP]

kennyd,

What is the pressure rating on that flexible pipe in your setup. It looks like a water heater connection hose.

I am pretty sure that braided hose is teflon lined high pressure high temp air line. Trucks use it from the compressor to the air dryer.
Bill

 

[glc24]

I swear,is anything from that country worth a crap
All those fittings are schedule 40,and 150 is their max. If you're not putting out more than 100-120 from your compressor,they're fine. I know they are more expensive,but schedule 80 fittings are 99.9% flawless,even the imports


Greg

 

[ray66v]

I know they are more expensive,but schedule 80 fittings are 99.9% flawless,even the imports
Greg

That has not been my experience.

Parts made for the space shuttle, are not 99.9% flawless.