Burying Galvanised Steel Conduit

[bailes1992]

I was wondering if any of you have any experience burying galvanised steel conduit?

My current plan is to make up the conduit, T-Wash it and give it a couple of coats of primer and hammerite before I sink it in the ground but I'm wondering if it will be enough? My Father has suggested covering it in heat shrink before it is buried? Is it needed?

The conduit will be the only CPC to an outbuilding so it's essential it cannot corrode over time.

And yes, I could run an SWA but I don't want to.

Sam

 

[Pete999]

I was wondering if any of you have any experience burying galvanised steel conduit?

My current plan is to make up the conduit, T-Wash it and give it a couple of coats of primer and hammerite before I sink it in the ground but I'm wondering if it will be enough? My Father has suggested covering it in heat shrink before it is buried? Is it needed?

The conduit will be the only CPC to an outbuilding so it's essential it cannot corrode over time.

And yes, I could run an SWA but I don't want to.

Sam

SWA would be my choice, why the reluctance to use it?

 

[Deleted member 26818]

It will corrode.
Perhaps your precautions will slow corrosion?

 

[KEV 1 N]

If you must use conduit, then I would pull in a separate CPC. I have come across several instances where conduits buried in concrete/ plaster have failed miserably in regards to acting as an earth, although they are 40/50 years old....install a separate earth conductor.

 

[Octopus]

Why complicate matters? - SWA every time for me

 

[snowhead]

It's steel, it will eventually rust away.
The screwed joints, if any, will corrode and you'll loose your CPC.
Heatshrink could trap moisture.

 

[snowhead]

Why complicate matters? - SWA every time for me

The O.P posts on LOTS of other forums, usually car related.
He's,,, unusual in his approach to things sometimes

 

[Octopus]

The conduit will be the only CPC to an outbuilding so it's essential it cannot corrode over time.Sam

What you are proposing to do is not acceptable.

If you are a spark you should know this, if you think you will be getting a spark to sign it off - they won't

Would you fit worn out tyres to a brand new car and race it around a track?

 

[KEV 1 N]

I once came across a 95mm 4 core SWA (installed 2007) where which was ran underground in a duct from a substation, ran downhill to a building. Where it was glanded into the section board was completely corroded as were the SWA armouring strands, could only presume the outer insulation was damaged during installing in the duct, and water has got in, and wicked its way out of the gland...luckily there was a separate earth cable installed!

 

[willy fixit]

When you say "cps" do mean main earth - exporting pme? What's in the outbuilding services wise? does anything need bonding?