pipe installation

[R1976]

Hi,

I have been asked to install some coldroom pipes on cable tray, seeing as the liquid pipe is not lagged, can anyone see a problem with this?

It will help with protection as its on a mezzanine floor where people can walk over them.

I have done this before and cable tied discharge and liquid lines from a close control unit directly to a cable tray. Yes it did look s***.

How do you all do it?

[Frikkie]

I would not strap a copper pipe to a steel tray without a plastic standoff clip. Different metals hard together can cause fast corrosion.

[nick uk]

insulate liquid line and tie wrap both together

[multisync]

Cant see any problem at all, just cable tie the liquid to the insulated suction -it's how it's been done for years and years-If price allows insulate them both

I have never heard of a problem with a copper pipe on a cable tray causing some electrolysiscorrosion-Perhaps Frikkie can show us actual examples?

However if there is a chance of people treading on it then for protection, you should double up the tray to make a tray/pipe sandwich

[Frikkie]

Cant see any problem at all, just cable tie the liquid to the insulated suction -it's how it's been done for years and years-If price allows insulate them both

I have never heard of a problem with a copper pipe on a cable tray causing some electrolysiscorrosion-Perhaps Frikkie can show us actual examples?

However if there is a chance of people treading on it then for protection, you should double up the tray to make a tray/pipe sandwich

Hello Multisync,

I don't have any pictures of corrosion but electrical regulation in many areas forbid laying bare copper earthing wires in tray without insulation. Corrosion is moisture related.
Quote.
A bare copper equipment grounding conductor should not be placed in an aluminum cable tray
due to the potential for electrolytic corrosion of the aluminum cable tray in a moist environment.
For such installations, it is best to use an insulated conductor and to remove the insulation where
bonding connections are made to the cable tray, raceways, equipment enclosures, etc.
Source here (http://www.scribd.com/doc/17252316/Cable-Tray-Manual?autodown=pdf)
Aluminum is worse than steel but any different metals in contact will corrode.

[lowcool]

your better off to install suction line so as no compression of pipe insulation occurs,i prefer to tape the liquid line,if compression is a problem use insulation with a larger wall thickness

[Kp3]

put the liguid line behind the insulated suction pipe. 6inch of armaflex tape wrapped round both pipes then cable tie to tray. The tape will stop the cable tie cutting into the insulation

[R1976]

Thanks guys,

If the liquid line is insulated will this effect the subcooling?

In superstores we lay pipes on unistrut with Armaload glued to it. We tape the pipes to each other with Armaflex tape. I suppose you could put a small section of insulation, say 50mm, around the pipe where each cable tie is.