How to bury steam lines if you have to--

BobV

Hi,

I previously posted that I have numerous underground (under 10" concrete also) steam pipe leaks. Two pipe system, built 1928.

My insurer has actually agreed to do the destruction/construction to re-pipe this whole area of my house (about 1200sf with a second floor above that also gets steam from the rotted underground lines). 

Soo, what's the best way to protect the replacement underground steam lines that will be installed?  It has been suggested to build concrete trenches and run the pipes in them, but I'm sure the insurance co will not pay for that. So what could I wrap the pipes in to best protect them with modern materials?  I think they have to be insulated first or I'll be heating mother earth!

Thanks in advance for your advice,

Bob V

Charlie from wmass

wrought iron pipe

was always specified on jobs with underground iron pipe. I am not sure if it even is available anymore. trenches are to only proper way to do this though. If direct burried the fill needs tested for PH and salts.

ALIGA

what are sewer pipes made out of

i know they are buried in ground

Rod

Need more Info

Hi- What exactly are these pipes- pipes that supply steam to the radiators or wet return piping?

- Rod

Jamie Hall

Sewer pipes...

Depends on the size. Big ones (like really big) in the bad old days were often brick.  Now they are concrete.  In more normal sizes, clay tile was once the preferred material.  More recently asbestos cement, which is excellent (but guess what happened to that product).  Polyethylene is common, but needs care in backfilling.  PVC (polyvinylchloride) is sometimes used, but is brittle (relatively speaking).  ABS (alkylbutadiene styrene) is common, particularly for storm drainage.



Wrought iron was used very little for sewers; too expensive.  Cast iron ditto, plus it is brittle.  Steel never -- corrodes much too fast unless protected (e.g. gas and oil pipelines are steel, for strength, but are protected by multiple coatings and cathodic protection systems -- and they still need to be constantly monitored for corrosion).



I might add that for steam lines -- either supply or return -- I would go with Charles and would always put them inside a ventilated conduit or trench box, never direct burial.  But that's just me?

Hap_Hazzard

What are sewer pipes made of?

Cast iron, ceramic, PVC, styrene, HDPE...

Hap_Hazzard

Must be a misnomer?

Wrought iron would be a terrible thing to make pipe out of. It was used when malleability was required before they had mild steel, but mild steel has been around for over 150 years. Wrought iron is just raw pig iron with lots of slag in it.

jumper

what size ?

In small sizes soft copper ? Flared connections ?

And I'd run it through some oversized conduit. In case you want to run something else someday. Hopefully the conduit is sloped for drainage and don't forget ventilation.

Charlie from wmass

No wrought iron

usually imported from the UK. Byers. It had a red stripe on it. It is even in Caleffi book #4. It was sold as being more rot resistant than regular steel pipe.

BobV

What pipes for burying--

The pipes are 2 1/2" supply steam vapor and about 1.25" returns. Must be well over 70 linear feet of each.  The original installer in 1928 used asbestos insulation, then a sheet metal material over the asbestos, then tar.  --lasted 85 years-- but that's not long enough!

Is it possible to sleeve them in large 6-8"PVC? 

Thanks for all the help,

Bob

Charlie from wmass

Yes you could sleeve them and have

access pits where there are tees or changes of direction.

pipeking

what u have to use is

pe coated steel pipe. u can get your standard black pipe with a PE coating on it. then there is a tape to do the joints, and i think there might even be a shrink wrap. but yes this direct bury pipe whith a PE (just like coated oil line) will last forever. now if your worried about the pipe getting eatin from the inside out, well then u got bigger problems!!!

J.A.

What will the lines be going through?

I've often thought about this for people with buried returns. I have no experience with actually doing this but clearly it seems the Dead Men who set it up originally thought about it as they insulated the pipes then wrapped it with sheet metal then tarred it closed. 85 years is a good amount of time, nothing lasts forever. Anyway, to your point: will the lines just be buried under earth or go through concrete as well? I ask because I don't know if concrete eats away at PVC like it would plain pipe. My thoughts would be pipe, insulation, and then encapsulation with PVC like others have mentioned. As long as you seal the PVC that should take care of any moisture problems and allow the pipes to rust from the inside out, uh, naturally.

SWEI

Polypropylene

I'll again suggest that polypropylene has the potential to make an excellent condensate pipe.