Pipe stress on a pipeline 1

[Crusader911]

I have a small project that ties into an underground pipeline. The pipe will be at ambient temperature, so do I need to do a pipe stress analysis? I know how to analyze buried pipe, I just need to know whether it needs to be done here. Other information - the pipe will be connecting to a booster pump and a launcher/receiver, but I would think that the stresses on the nozzles will be fine as long as the pipe is well-supported.

 

[BigInch]

Its only at ambient temperature every day. The problem could be that the connecting pipe is installed in the summer at an ambient temperature of 90F and some day winter arrives and leaves you with an ambient temperature of
-10F. The 100 degree difference could leave you with enough tension to rip that nozzle off, or at least pull the pump out of alignment.

**********************
"The problem isn't working out the equation,
its finding the answer to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[BigInch]

Remember allowable pump nozzle loads are very very low. Some not even 50 to 75 lbs, even for a rather large pump.

**********************
"The problem isn't working out the equation,
its finding the answer to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[Crusader911]

Thank you. I'm going to follow your advice and analyze it. I'd rather have someone tell me I'm being too picky than miss something that ends up causing problems. I've had many painful experiences with API 610 nozzle loads - my standard practice is to analyze pipe of any temperature if it connects to rotating equipment.

 

[BigInch]

That's the smart way.
Pumps allowable loads don't leave much of a choice.
You must be absolutely sure that there is enough flexibility to keep those forces low low low.
If you can't see it, run it.

On the other hand, I wouldn't worry all that much about stresses on the launcher. The launcher will probably move and aleviate them. Movement may be another story. I like to put launchers on skids using slots for the anchor bolts and let them move as much as I can.

**********************
"The problem isn't working out the equation,
its finding the answer to the real question." BigInch

http://virtualpipeline.spaces.live.com/