Hello everyone



I read some article on web, which discusses about

1-dummies on elbow

2-trunnion on vertical pipe


There is some confusing interpretation about sif


A) Does sif increase / decrease when a dummy is welded to it, if sif increases how much should actual stress be limited to ? 90%?

B) Flexibility factor decreases? , and if so it will have impact on flange check near control station!

C) what is the most conservative/ practical way of assuming sif at dummy on elbow or trunnion on vertical pipe

Is it value 2.1 or welding tee or unreinforced tee
Is it good to assume sif of unreinforced tee!!

thanx

please look here:
http://mydocs.epri.com/docs/public/TR-107453.pdf

http://www.epriweb.com/public/TR-110162.pdf

Based on some FEA calcs that I did:

1) SIF increases ( this is mainly due to geometric discontinuity in the model)

2) Flexibility factor decreases.

Regards