stresses due to weld 1

[amith014]

Hi all,

I am doing FE analysis of pressure elements with saddle supports.

One of the saddle support is fixed and other is free.

The shell and saddle supports are connected using weld elements.

My question is,

High stresses are generated at the weld locations of movable saddle., why?

Whether these stresses can be neglected?

And also high stresses are generated at the nozzle and shell weld junction, why?

As far as i understood the shell is bulging, hence the stresses are generating at these location.

Please clarify.

 

[metengr]

Fusion welding can generate residual stresses in base material surrounding the weld region that can reach values as high as tensile yield of the base material, and therefore should not be neglected. The reason for residual stress is the heat from welding locally melts base material and residual stress is generated from solidification.

 

[TGS4]

High stresses are generated at the weld locations of movable saddle., why?

Because it's a discontinuity.

Whether these stresses can be neglected?

Why would you think that? These discontinuity stresses are real.

And also high stresses are generated at the nozzle and shell weld junction, why?

Again - the discontinuity stresses.

To what Code are you performing the finite element analysis calculations? If ASME Section VIII, Division 2 (2007 or later), most of the answers that you seek are in the Code. If you have specific questions about how to interpret your FEA to Code, I would highly recommend that you search the archives here. This topic has been discussed many times.

If you have a specific question that you think has not been answered, then please return with your question.