Hi all,
I am working on a wellhead line of material A106-B with 77deg C and 140bar.
I have just started my career in stress analysis but i have worked for two years in layout. I have modelled the line with sufficient supports. now, the system passed code compliance & the stresses are within limit.
Now, can i confirm the system is ok & secured and take the reports to finalise it?
If the code compliance is passed, the system is safe?
or i have to further check out anything else?
If so, what are the steps i have to take after code compliance passed?
Since i am new to this field i need this basic help. please give me a basic idea of the requirements in stress analysis. I will appreciate it if anyone spares time and help me in this basic query. thank you in advance.

What about fatigue ? Equipment loads ? And is there wellhead thermal displacement ? All fundametnal issues.

With 2 years in layout and obviously no stress experience, you need to find an expert in your company or elsewhere to guide you. Othewise with the best intentions, you may engineer a disaster that will destroy at least you career and possibly the lives of others.

Get help a.s.a.p., good luck.

Dear Moverz,
Thanks for your reply. There is one senior person in my company. i approached him. but he advised me to refer net or articles and learn by myself(however, he will finally check & validate). thats why i sought for guidance here.
I have considered +-50mm thermal displacement at the wellhead. and modelled wellhead as a rigid element. i anchored the other end of the line which actually goes to a vendor package (Production manifold). And provided guides & rests approbriately & passed the code compliance. the stresses are within limit. But the vertical displacements are more than -100mm at the nodes near well head where the imposed displacements are given.
Does this displacements need to be reduced even if the stresses are below allowable?
And also the loads at supports are more than 80KN in the Operating conditions. do i need to take care of these elements?
(But, Still the stresses are satisfied & the system is passed). Do i have to concentrate on any other parameters?
I would appreciate if anyone advise me on this basics. Thanks in advance.

If a line passes code compliance in CAESAR II it doesn't mean that it is safe, well designed... Each type of pipe line has engineering requirements that single software or even a code cannot solve.

As an example I just walked 40 bar 435 C steam line. CAESAR II calc would most probably say the line is OK. The trouble is that the line doesn't have one single guide or ANC between the ends. Not good. Line would be in next town if an other line did not stop its walk.

In pipe design like any other engineering you need experience. Reading helps.

Other things you should also consider - do you have any lift offs on any supports? ie the pipe is sitting on the support under a gravity load and then growing off the support under thermal loads. If so then you may not actually be code compliant and have to recheck your model again with these supports removed.

Also check support loads - you may have a system that is code complaint and have huge support loads. (ie you can model a straight length of pipe in caesar with 2 anchors in-line and get the piping code complaint but you will see huge anchor loads (Caesar does not consider buckling).

regards

Shan,

There’s a lot more in this field and you will end up a year before reading all the documents in this web(I MEAN PURELY READING) that will not be good in your work. I spend 14hours at my office and 6 days a week. lol! Just to be at my best to make an assurance of my work. Reading newsletters and trend discussions(interpreting it base in the code). I even have no time to read my kellog.. Well if you got a book from Sam Kanapan then you can read that first. It's basic principles will be adequate for now.
Finally, It’s up to you on how you talk to your senior.

(learning thru this way is quite hard "YOU MUST BE CONSISTENT ON WHAT YOU FEEL AND YOU MUST FEEL FOR THIS WORK").

Regards!