Stress Intensity Factor (SIFs)

This may not be the same thing but, many years ago, it used to refer to the effect of the flattening of the pipe through an elbow under bending moment.

Rizwan...

I guess that GOOGLE is somehow not available on your computer system..

There is an excellent explanation on the Paulin website.....under the Library tab

www.paulin.com

What type of stress analysis software are you running and what type of piping systems are you analyzing ?

SIF ncoperates the fatigue life for the fittings and the branch connection in the piping system. Please go through the Appendix D of ASME B31.3, you will find your answer. Regarding softwares(i am talkking about autopipe software, no experiance with CEASER II)they take branch connection as welding tee by default and the user may change if he/she desires. For non standard connection you may calculate it through pipe mill software.

e.g if you have pipe to pipe connection (stub on) then you will used the SIF of unreinforced tee from Appendix D. But if reinforcement is needed, you will now calculate the SIF. This can be done through pipe mill software.

I think the problem is resolved.

Best Regards

Ikram Ali Khan

Good catch...

Es correcto la descripcion, pero podemos agregar algunos detalles

- Durante el diseña cañerias, nadie piensa el este factor SIFs y es por ello que parece

estraño y no sabemos para que se usa

- El factor SIFs es estrella durante los estudios de flexibilidad de las cañerias

que estan somentidas a temperaturas mayor de 60 grados Centigrados y en lineas de Vapor absolutamente es necesario hacer Stres Analisis

por la dilatacion de las cañerias, somete los codos y tee a esfuerzos, y es necesitan calcular el Stress para verificar si podran soportar los esfurzos

- Existen programas para el calculo de Flexibilidad , por ejemplo el CAESAR, estos programas tienen incorporado estos factoras de SIFs y solamente el operador cargas la configuracion y los accesorios y en forma automatica los aplica

- Si puede calcular en forma manual ver la ASTM 31.1 y 31.3

Saludos a todos

Alberto

hey alberto,

can you translate your comments in english version since as far as i know all forum are in english language...so far for that, one concern regarding this matter:

any experts in this CR4 forum can explain what is the effect of pressure on stress intensification and flexibility factor in the piping system?

thanks in advace!

Good catch...

It is correct the description, but we can add some details

- During the pipes designs, nobody thinks the this factor SIFs and it seems
strange and we don't know which is their use

- The factor SIFs is star during the studies of flexibility of the pipes
that they are subjected to temperatures bigger than 60 Centigrade grades and for all Steam lines it is necessary to make Stress Analysis
for the dilation of the pipes, it subjects the elbows and tee to efforts, and it is they need to calculate the Stress to verify if they supported the efforts

- Today in the market programs exist for the calculate of Flexibility, for example the CAESAR, these programs have incorporated these factors of SIFs and only the operator loads the configuration and the accessories and in automatic form it applies them

- You can calculate in form manual, to see the ASTM 31.1 and 31.3

Greetings to all

Alberto