Can any one tell me How to calculate allowables of forces & moments for tanks & heatexchanger

Your company should be having an Equipment group ( some companies use the name Mechanical Group). Talk to them.

Usually every company has either a corporate pipe stress analysis guide and or a project specific pipe stress analysis guide which specifies the allowable loads.These loads are established in discussion with the Mechanical/Equipment group and also with the client.

For pressure vessels read ASME B&PV code Sec VIII DIV 1 and 2.This will give you an idea of the allowable stresses and the method of computation at piping-equipment connections.

Just out of curiosity, don't you have any experienced pipe stress engineer in your company? You should be working under his/her guidance.However if your company is not having any experienced stress engineer, you should talk to your HOD and ask for help. Forum members cannot be checking your work which I am sorry to say is badly needed from the standard of your questions.

Regards

Mr. Anindya...

This Forum is made for discussing something and helping out each other for a particular topic.

I had asked the question for my curiosity and knowledge, not to check my work by the forum members.

If you know the any standard available for asking a question on this forum, then let me know.

Moreover thanks for giving idea about reading some Code and STD.
But i think you must be in your limitation of words while answering, otherwise no need to reply.

With Regards
Aditya Singh

Anindya, I completely agree with Adi, even if your tips are very usefull.

Adi, for nozzle allowable on tanks, read Appendix P of API 650. There is a useful method of calculation.

Since this seems to have turned into a newbies vs. graybeards thread, let me weigh in on the side of the greybeards.

1. You do not CALCULATE allowable stresses for nozzles, for the most part. There are standards (Heat Exchange Institute for shell and tube heat exchangers, and API 610 for centrifugal pumps, for example) that provide guidelines, but they are for the protection of the equipment and often do not provide limits for any one nozzle. (In particular, the HEI standard gives a method to calculate allowable loads for each individual nozzle, and a method for combining them into an overall load that is also limited. Often the overall limit controls.)

2. Normally, the equipment vendor provides allowable laods at nozzles for his equipment. If your company did not require them to do so with their bid, shame on your equipment engineers. Tank nozzles can be analyzed using the Bijlaard methods of WRC 107, but this analysis is now considered to be of limited value, sincve FEA is available.

3. Engineering is a cooperative effort. No one is expected to do it all by himself, and those who attempt to do things outside their area of expertise should be discouraged. Pipe stress analysis is enough for you to bite off in one sitting, there's no need to try to become an equipment expert in the same time frame.

4. Pipe stress analysis is not something you should attempt to learn by yourself, even with the help of this discussion forum. If you have no experienced piping engineer to learn from, you should strenuously try to find a job where a competent mentor is available. The mere fact that you have chosen to ask such an elementary question (which stands on an erroneous assumption as Anindya has pointed out) suggests that you have no one to mentor you. The fact that you are outraged to have your lack of knowledge pointed out to you does not speak well of your maturity. One who asks for free advice should take great pains not to insult those who respond to his request!

5. A number of people from China and India appear to have hacked into CAESAR II and, because they have the software available are presenting themselves to the world as pipe stress analysts. If you are one of those scum, I spit on you. If you have a legitimate copy of the software, then you have a legitimate right to have your questions answered, although as I have pointed out, you have no right at all to have experienced engineers endorse your erroneous understanding of the profession.

6. There's quite a bit more to doing pipe stress analysis than putting numbers into CAESAR II so that the code compliance report says you passed - if it were otherwise I'd have gone on to something more challenging a long time ago.

The age old battle of youth vs experience youth wins only for speed experience rules in the end as long as physical prowess is not involved, and even with correct training we see these gaps closing. It has always taken more than a fast mouse a pc and a glib attitude to do this work successfully.

So if you ask a vague question like "how do I design linear particle accelerator?" expect a glib smart crack answer from those who are experienced...

Use the search functions in this forum first and read the online help and then ask reasoned intelligent questions.... as I have said for the 3 millionth time

This message is for the Engineers those who do things as like above..

I just want to pass the message that "Those who reduce the stress for the piping must also reduce their mental stress in their real life on others." The people who dont have the ability to reduce the mental stress is very dificult for them to produce a good stress results.

Also I just want to clarify the point no.5 of Mr. CraigB. I kindly as Mr. CraigB not to specifically mention the country names as like and I think Mr.CraigB being a Professional person may not use such kind of words again.

This message is not to criticise any one and the discussion forum is very excellant way of approach to discuss the software and technical details. It is not to criticise any one of the queries or suggestion.

Dear all piping and equipmet specialist & experts .


Mr.CraigB ,Mrpaldex ,Mrdiegosurf82 ,Miss anindya

I thank you for all your good and bad comments on the question i have asked

Now i am very sure that When somebody want to know something if he will ask in this forume he will get the answer definitely.


Mr.CraigB
When man get experienced in life he will be more submissive and will guide the jounier properly i think i am jounier to you in terms of knowledge
so you have all rights to shought at me but at the same time you should not throw your frustation on the other people.

Regarding China and India i would like to say - we only know how to run the software its true but your all companies are opening offices in india
and want to recruit indian. Spitting on others face is very easy but wipeing out others spit is difficult but we are doing the same thing.The mistakes you people do in abrode is being wiped out by us here in india.Because we asian are humble and submissive and adptable people.
The day will come when all the europe and americe will come to india to do business i think you dont have any idea about india & china in your country i thing all the comodities are from india and china because you only know stresss analysis you have not done MBA or want to know even what go around world.At last i want to ask mr Mr.CraigB can you be my mentor ?????



Mr.paldex
Thanks alot to mr padlex matured & professional man.

Adi Singh

I am originally from India and hence I am not surprised at your outburst. Having worked in India for 13 yrs, I have seen the level of strses engineers in India ( except for few who were exceptional) , most of them can't even draw a free body diagram.

India has definitely produced some excellent minds ( poets, artists, scientists and engineers) but on an average the quality of stress engineers in India can easily be judged from the level of questions most of them put in this forum and their attitude. It is people like you who put the level of stress engineers in India at an abysmal level in front of the world.

About opening offices In india it is decided based on low cost and high productivity ( those who decide on sending jobs there don't on many occasions know the quality of work delivered or the capability of the engineers).Finally the main offices have to do most of the corrective job.

I have worked in India offices of most highly reputed Indian as well as MNCs hence kknow these things a little bit better than you.

Indian best minds leave India for very good reasons and the remainder ( most of them , some are really exceptional, for example the person from whom I learnt pipe stress analysis)are people like you.

Regards





Regards

ANNINDYA
WHAT YOU ARE ITS SHOWS YOUR LEVEL
AS FAR AS HIGH PRODUCTIVITY CONSERN YOU ARE CONTRADICTING YOUR STATEMENT I THINK YOU NEED TO READ BOOKS MORE BECAUSE YOU ARE SAYING THAT HERE ENGINEERS ARE NOT GOOD SAME TIME YOU ARE SAYING THAT IN INDIA YOU OFFLOAD WORKS TO INCREASE PRODUCTIVITY SO WHAT IS TRUE??. YOU PEOPLE AFTER LEAVING INDIA THINK YOU ARE THE GREAT SCIENTIST. THE PERSON WHO CANT RESPECT HIS COUNTRY IS JUST ESCAPIST.IF I WILL ASK YOU TECHNICAL QUESTION U WILL NOT ABLE TO ANSWER OK YOU PEOPLE SLEEP AT WORK. YOU ARE THE SAME PEOPLE WHO SOLD THEMSELVES TO BRITISH . AS FAR AS STRESS ENGINEER CONCERN NO STRESS ENGG CAN LEAD ANY PROJET AND ENGG LIKE YOU IS ONLY A STRESS ENGINEER WHO HAS NO BRODER VISION.OK TAHNKS FOR SHOWING YOUR LEVEL.

Finally the main offices have to do most of the corrective job.

YOUR MAIN OFFICE PEOPLE NEVER DO WORK THEY AGAIN OFFLOAD THE WORK TO OTHER PARTIES AGIN THEY DO MISTAKES AGIN ITS COMES TO INDIA.OK I KNOW WHAT U DO THERE DONT THINK WE ARE NOT AWARE ABOUT YOUR LEVEL OF ENGINEERING.

YOU PEOPLE WILL WANT TO STAY THERE SO U CAN PALACATE THE ENGLISH PEOPLE BECAUSE THEY GIVE YOU BREAD AND BUTTER BUT WE ARE CAPABLE OF EARNING THE SAME HERE AND GOING ABRODE I HAVE NO OFFERS IN MY HAND TO GO TO USA AND UK ,GERMANY BUT I DENIED BECAUSE I DONT LIKE TO WORK UNDER BRITISHERS.

WHAT YOU SAY I ALSO KNOW ABOUT ALLOWABLES AND FORCES OK BUT I ASKED BECAUSE TO KNOW IF ANY STANDARED THUMB RULE TO FIND OUT ALLOWABLES AND FORCES FOR TANKS AND EXCHANGERS JUST LIKE WE DO IN TURBINE INTEGRAL PIPING.

ANINDYA TELL ME HOW TO SOLVE THIS.

Actually i am doing analysis of a Hot Reheat line 24inch 585 Degc39bar press

of boiler at saftey valve discharge my boiler vendor has given a horizontal force of 20KN to be act at the saftey valve discharge also the vertical force will be 2oKN while applying the both in Operating + Saftey relive valve case i found the straess in occasional condition goes high that is 97% i want to limit it by 85% .

Can any one tell me as per my knowldge 20KN load in the horizontal direction in saftey vale discharge is too high also tell me how to reduce the stress at the stub on which saftey valve is mounted i have already tried this with fabricated TEE still it fails in stress i cant put Reinforce pad because its P-91 material please help me

Adi,

First, I would not respond to your personal observations and suggestions regarding my level and my capability.

I think I am older than you and quite well known to the industry , so responding to such things is below my dignity and also since it is from someone who perhaps is of my younger brothers age, I really don't mind.It is good to know that India has not lost good engineers like you who will definitely make their counry proud with their excellent knowledge of engineering and english and good to know that India has lost engineers like me who lacks self respect and perhaps knowledge.

However, as your senior and somebody who comes from the same country as you, I hope that you remember an old saying in sanskrit ( not in english) that to learn you have to have humility.

Regarding your technical query,first look into the calculation of computation of the 20KN force and check if you agree/disagree.Reaction force computation and some interesting discussions can be found in API standard RP 520 Part II and B31.1 Appendix II and also the paper by Brandmaier and Knebel.Let me know if you need this paper.

W/o going in depth into your system, I can say that considering 20KN as a correct and correctly applied force and your CAESAR II model is absolutely correct ( which includes proper load case definition and combination), an analysis of the highly stressed location can be done using Finite element method and the rules of ASME SEC VIII DIV 2APP4.

Regards

hello anindya sir,

Can you please give the paper by
Brandmaier and Knebel i will be highly greatful to you.

Pl. find attached.

Regards