PDA

View Full Version : copper or steel


mbc
16-10-2009, 07:57 PM
Why we use in CFC gas Copper pipe and we do not use steel pipe ?
lowcool
16-10-2009, 10:55 PM
which is easier to work with and less likely to contaminate?
NH3LVR
17-10-2009, 01:55 AM
Actually many larger systerms are piped in steel. It works very well where the strength of steel piping is required. It is of course more difficult to insure cleanliness.
Sledge
22-10-2009, 03:58 AM
Actually many larger systerms are piped in steel. It works very well where the strength of steel piping is required. It is of course more difficult to insure cleanliness.

I have seen larger systems for Ammonia pipe in steel, but never ***** systems...I didnt know you could use steel??
Grizzly
22-10-2009, 05:42 AM
I have seen larger systems for Ammonia pipe in steel, but never ***** systems...I didn't know you could use steel??

Hi Sledge.
Yep NH3LVR'S is correct.
Check out any large cold store if you get the chance.
Preferably the older ones on R22. (all Steel pipework ).
Although Copper seems to be the favourite nowadays. It used to be a cheaper option but with the price of copper now.
I am not so sure?
Cheers Grizzly.
Frickman
22-10-2009, 07:29 AM
It depends on the end user also. Some of the bigger company now adays like some of the piping being stainless steel!
goshen
22-10-2009, 04:46 PM
It depends on the end user also. Some of the bigger company now adays like some of the piping being stainless steel!

yep seen these on small units and large ones stainless steel it is expensive but lasts forever!!:cool:
mad fridgie
22-10-2009, 08:28 PM
Slightly off subject, I was watching a gas contractor fitting a 24" plastic pipe (or should I say man made material) The pipe came in a large radius coil. They unrolled ito the trench, when it came to the joining of the next piece, I ask how long to join (welding) the reply was to X ray standard a long time, how long I said?
"nearly an hour" They had this fancy machine, whipped around the pipe in no time.
So I decided to do a bit of research (I was at this time looking at a NH3 job with a really long "main") Got on to the design engineers, gave them some spec, temps, pressures, ammoina and hydros ammoinia.
They came back that they saw no problem using plastic pipe. I wonder if any body has used this before?
PS; Did not have the balls to even but in front of the client!
Magoo
23-10-2009, 12:55 AM
mad fridgie,
probably a good call regarding plastic pipe, should be referred to SGS for clarification. They struggled with sched., 10 stainless to replace sched., 40 steel.
mad fridgie
23-10-2009, 01:05 AM
mad fridgie,
probably a good call regarding plastic pipe, should be referred to SGS for clarification. They struggled with sched., 10 stainless to replace sched., 40 steel.
Not really in this market now a days, (could not handle the paper work!)
US Iceman
23-10-2009, 03:55 AM
Carbon or stainless steel works fine. Plastic is not recommended and not listed as acceptable refrigerant pipe here in the US.

I've used carbon or stainless on custom built packages to provide increased durability. Copper is essentially a weak material for some applications.
desA
23-10-2009, 05:46 AM
Aluminium clad tube, with copper outer flashing seems to be fairly popular in SE Asia, due to the copper price.
Josip
23-10-2009, 03:25 PM
Hi, all :)


Slightly off subject, I was watching a gas contractor fitting a 24" plastic pipe (or should I say man made material) The pipe came in a large radius coil. They unrolled ito the trench, when it came to the joining of the next piece, I ask how long to join (welding) the reply was to X ray standard a long time, how long I said?
"nearly an hour" They had this fancy machine, whipped around the pipe in no time.
So I decided to do a bit of research (I was at this time looking at a NH3 job with a really long "main") Got on to the design engineers, gave them some spec, temps, pressures, ammoina and hydros ammoinia.
They came back that they saw no problem using plastic pipe. I wonder if any body has used this before?
PS; Did not have the balls to even but in front of the client!

... they saw no problem :eek:

... I was using PE pipes for brine CaCl2 (calcium chloride) for ice cream machine .... too much contraction ... all hangers were movable ... night mare to install it in a proper way ... but regarding of nature of CaCl2 we had to use plastic pipes and iridium HE

.... plastic is maybe good for positive temperature ... but at -40C/F of liquid ammonia .... I'll keep with LTCS and with SS ...;)

of course maybe I'm not right ....

Best regards, Josip :)
US Iceman
23-10-2009, 03:34 PM
of course maybe I'm not right ....


Hi Josip. I still need to send you the book information. I've been busy. :o

No, I would say you are right. I would not use plastic for anything except low pressure water piping or gravity drain lines (PVC). Using plastic on ammonia piping would be a disaster IMO.

Calcium Chloride was used for years with carbon steel pipe. One of the issues I remember is that you have to check the pH of the brine. It can absorb oxygen from the atmosphere, which causes the pH to change. Then the brine becomes very aggressive in corroding the pipe. I saw this first hand on an old ice skating rink that used an atmospheric open tank for the brine system.:rolleyes: It was not good, let me tell you....