District Steam and condensate piping

asme B31.1 Power piping.

FROM THE FIELD;

DO WHAT RIED SAYS.

MIKE

"Be very careful with manhole design, I knew a fitter who suffered major burns and had his partner killed in a steam valve failure in an enclosed environment."

Hence OPEN TOP pits with grating covers.

"Ricwil" manufactured lengths of insulated steam supply & condensate return piping inside a sealed section of corrugated culvert pipe for direct burial. Pipes welded together, insulated, outer cover applied and welded in place and welded seals protected from corrosion. See list of specifications, etc. by googling for "Ricwil."

Experience with steam quickly resulted with manholes soon becoming grate covered open pits.

Can anyone get me information on RicWill? I have a failure in a four pipe system....and would like a rep on site when we open up the conductor to make the steam repairs. If you want please reply directly to Mick Harris e-mail: harris@ohio.edu.

Thanks, Mick

I have always tried to install steam in a tunnel when possible for many good reasons. We do have one underground 4", 150 lb. steam line supplying the box plant that is adjacent to the paper mill I work at. Seems that we are always having to dig it up for repairs though and I would not recommend direct burial. You will need someone who knows steam pipe design to design the supports and do all the expansion calculations. I would not risk the liability incurred in public place with out having a stamped drawing that follows at the least ASME B-31.3 and would prefer B-31.1 myself.

pipewelder

Thanks, all, for your responses. I have since reviewed the Ricwill website and see they have it pretty well figured out. We're also looking into pre-fabricated concrete trenches that double as sidewalks when completed. We may end up with a combination of trench for mains and Ricwill for branches into buildings. Turns out there are 7 or 8 buildings to serve, not two.

Curious, they only run 10 psig steam right now, and still rely on steam pressure to lift condensate in several places, including the few manholes they have main traps in. I'm sure there is a way to do the ecenomics to figure out an optimum steam pressure, (fuel use, equipment capacities, pipe size/schedules, etc.) but does anyone have any feedback on this issue? They're already planning on an operator, so the 15 psig limit won't make a difference. Sems like somewhere around 50 psig would be much better for condensate systems and we could still use 150-lb valves, standard weight pipe, etc.

Thanks again,

Scott

The largest reported pre-insulated pipe job was supplied by Rozanco you should look at them too.

I think you meant "Rovanco"?

Permapipe from what I understand took over the Ricwil product. So at least you have a couple of competitors for assistance on the project.

The Nalco chemical campus in Naperville, IL, has a utility tunnel system that connects between buildings, so "Power Plant" workers do not have to go outside in the winter to check out other buildings. It also carries chilled water, domestic water, etc.

O'Hare Airport in Chicago also has a ring utility tunnel connecting the power plant to all 4 terminal buildings. It is huge with chilled water, high pressure hot water (400psi at 450F if I recall the numbers correctly), fire protection, etc.

It might cost extra money to install, but the improvement to reliability and maintainability shows up 15 years from now. O'Hare's tunnel is probably about 40 years old now. When I was in it around 2001, it was still in reasonable condition.