Crashing Load in Thing Wall Piping

[Vikoll]

Could you please shed some light on how to check for crashing load and for stress in thing-wall CS/SS piping to make sure they are not excessive for cases as follows:
- Bare pipe supported from the steel
- Pipe is on a shoe with no re-pad
If you can share a validated spread sheet for performing this calculation or refer to a proper source, your kind help will be truly appreciated.

Thanks and have a great day

 

[DSB123]

Vikoll,
What do you mean by "Crashing load" and what is thing wall piping. Do you mean "crushing load" and thin wall piping. If so I think your question is in the wrong forum. Post in the "Pipelines,Piping and Fluid Mechanics Engineering" Forum.

 

[Vikoll]

Thanks, DSB123
Of cause you are right! The question was about "crushing" load and "thin" wall piping. I will follow your advice and will be reading my posts before submitting. Sorry for any confusion
Vikoll

 

[Crusader911]

Vikoll,

What piping code are you designing to? If B31.3, the code refers to a specific part of the Boiler & Pressure Vessel Code for details on this calculation. Sorry, I don't have a spreadsheet.

 

[DSB123]

Crusader911,
Please provide specific number of Paragraph in B31.3 which states to use BPVC for this calculation of crushing load due to loading at a pipe support. I'd be very interested.

 

[Vikoll]

Crusader911,
Yes, I am designing to B31.3 and could not find the mentioned reference to BPVC pertaining to crushing load and local stress in a pipe wall calculation due to pipe support.
Please advise
Thanks and have a great day

 

[Crusader911]

The paragraph is 304.1.3, and it refers to UG-28. Reading your question more carefully, however, I see that you are talking about stress at a support point, and trying to determine if you need a saddle. There is an excellent discussion of this in the "Casti Guide to B31.3." I believe there's enough information there to construct a spreadsheet. If you do need a saddle, the AWWA has an empirical formula they use for determining the saddle angle, or you could treat it as a horizontal vessel and use Zick.

Before you do any of that, however, make sure your company or client doesn't already have a spec that covers this. One of my clients had a table that simply specified what pipe support to use with a given diameter for any pipe over 12".

 

[DSB123]

Crusader911,
I thought you would not be able to cite a Para in B31.3 or BPVC for the actual question raised. B31.3 does not address this nor does BPVC. It's always important to read the question before pointing someone in the wrong direction. As you say there are approaches which can be used. Roark's Formulas for Stress and Strain may be used also.