Pressure is neglected in stress analysis

[orca61]

Hi there,

I am a chemical engineer and as a project manager I am involved in stress analysis for piping. As our company rules are not very clear when to do a stress analysis by computer I read some manuals of bigger German engineering companies.

I found out that the criteria for stress analysis is always certain temperature related to pipe size.

Can some of you explain me in simple words why pressure is neglected. For me it seems that for a exhaust pipe of a Diesel engine( e.g. 4 ") with almost no internal pressure is more important to do a stress analysis than for a low pressure steam pipe (e.g. 10 bar same size).

Your help is highly appreciated

Orca

 

[DSB123]

Orca,
As a chemical engineer or even a Project Manager I will give you sound advice - Seek the expertise of a qualified Pipe Stress Engineer. I would doubt that a Pipe Stress engineer would dabble in Chemical engineering and I doubt that you would condone it. Each to his own and you obviously know nothing about pipe stress engineering by your question so seek out someone with the relevant knowledge to do the job.

 

[orca61]

Hi DSB8123,

you are right I know nothing about pipe stress analysis. As lomg as you have manuals, the way is easy. I have to find someone with experience to do the job. I personally find it easier to follow a rule when I know the background. That's why I posted a tecnical question.

Now it is time for advice from my side. As a piping engineer it is not only important to calculate your forces and momentums right, it is also important to explain clients, project managers or even chemical engineers in simple words why you do it at that place and in that way. Believe me or not it will help your career.

Orca