Steam main with "walking" hangers

JUGHNE

I have a 113'run of 3" steam main.  The straight 75' in the middle of this has hangers that walk as the pipe expands & contracts.  After adding hangers 5 years ago and checking today as we insulate the piping. some have moved enough to affect the slope of main.  They become cocked and get stuck at an angle.  The new hangers are "auto grips", 1 piece tear shaped with 3/8" farrows and 8 to 12 " of 3/8" rod screwed into "Sammie" side winders lags.  The original hangers are "fish hook" design with about the same lengths of hanging pipes and they do walk somewhat also.  The pipe is painted and completely uninsulated.  Will adding the new 1" fiberglass improve the issue.  The pipe hangs in a 55* area before steam is up.

gerry gill

If your insulating

i'd recommend you put a piece of sheet metal under the insulation extending a few inches on each side of the hangar and install a larger hangar that goes on the out side of the insulation. The pipe will move as it expands and you won't get noise from the hangars as it does so this way.

nicholas bonham-carter

Shower curtain

On such a long stretch of pipe, it would be nice to have a hanger like a shower curtain hanger with wheels to enable the pipe to move without disturbing the angle of the hanger.

The main problem is the elongation due to the pipe heating up, and that insulation will not help in itself. Maybe some wire ties next to the hanger points will prevent the creeping of the hangers.

Must be a big Sandhills job!--NBC

JUGHNE

Sliders needed

Thanks for considerations;  there were threads here talking about cut up milk jug plastic used to stop the noise of pipe creeping.  I'm thinking that may end up melting into goo between the temp and weight.  I'll probably keep things as they are.  It is now obvious that the longer the hanger rod the more swing is allowed and the less torque applied to the pipe clevis. (simpleton me).  All piping is located above suspended ceiling so this is more incentive to check things more often each year.  NBC-- this is the old sandhills church; how is your project coming?  Thanks also to Gerry. 

PS: I've hired a church board member who is half my age to install the insulation so he will "own" the system someday and know what to look for.

lza

Roller hangers or cal-sils

You might think about using clevis roller hangers, and insulating around the hanger.  Or cal-sil inserts and properly sized clevis hangers. 



I know cost may be an issue, but I would consider 1 1/2" wall fiberglass the standard for steam piping. 

Mad Dog_2

We call them "shielded" hangars in NYC

But what the venerable Mr Gerry Gill suggests is the same principle. On large long runs like that I like to use "roller" clevis hangars...wish I had a picture, but the pipe can roll freely to and fro as needed. Mad Dog

copperkid

Use roller hangers

I would use roller hangers with saddles.  We use these frequently on long runs when movement will be an issue.  They are tacked on the pipe , the insulation is installed around the saddles and placed underneath the pipe.  These work very well.  Also you could use 1/2in rod to eliminate some flex.