AMMONIA LINE
AMMONIA LINE
(OP)
I have some questions here.
1. In ammonia line ( dia 4", 6" ), is it recommended to use socket welding joint ?
2. What about inspection & test procedure ?
Best regard
Purnawan
1. In ammonia line ( dia 4", 6" ), is it recommended to use socket welding joint ?
2. What about inspection & test procedure ?
Best regard
Purnawan





RE: AMMONIA LINE
In general for high pressure system or piping containing hazardous material, anything above 2 inches should be butt welded. For 4" & 6" ammonia line I would say must be butt welded.
Then you should gamma-ray test it for welding quality before you pressure test it with water of low chloride content (assuming you are using stainless steel pipe for ammonia)to up to one and a half times working pressure.
This is a general procedure without knowing full details of your situation. You should check ASME B31.3 for chemical plant piping.
Paul
RE: AMMONIA LINE
But I agree that any line over 2" should be butt-welded.
RE: AMMONIA LINE
If for no other reason, economics dictates butt welds in larger diamter pipe. 2" pipe is the typical upper threshold for socket welding.
Many plants (most of my experience involves food processing operations) avoid hydrostatic testing of ammonia systems, and use pneumatic. This is because even trace amounts of moisture in these systems will cause operational problems due to ice crystals forming.
RE: AMMONIA LINE
Go with the experience of the ammonina manufacturers and distributers.
Most of what is said above is valid,... however check the following website and ask LaRoche specific questions about your storage/transfer systems
http://www.larocheind.com/
ASME B31.3 is the appropriate piping code; butt welded fitting are best above 2"NPS.....avoid water in piping systems.
let us know what you decide..........
MJC
RE: AMMONIA LINE