Hello vijay1983,
Well, you have asked the basic “good simple question”. The only thing that you did to complicate it is ask for Internet references. Well, here is my short answer to your simple question.
Actually, there are several helpful out-of-print books available on the used book market. Some of them have been mentioned many times in this discussion board. There are two good books CURRENTLY available to give you a very good head start in learning the artful science of piping structural analysis:
Process Piping: The Complete Guide to ASME B31.3, Second Edition, by Dr. Charles Becht IV,
http://catalog.asme.org/books/PrintBook/Process_Piping_Complete_Guide.cfm CASTI Guidebook to ASME B31.3 Process Piping (Fourth edition), ISBN: 0071364714, by Glynn E. Woods, and Roy B. Baguley
http://www.casti.ca/ (click on books and ebooks)
and for a preview ,
http://www.casti.ca/books_ebooks/lite/B31_3_lite.pdf and you might want to keep these “freeby's” handy
http://engstandards.lanl.gov/engrman/6mech/pdfs/D20-AppA-ASME_B31.3-r1a.pdf and
http://www.usace.army.mil/inet/usace-docs/eng-manuals/em1110-1-4008/toc.htm Some of the older books devote many pages to explaining “approximate methods” for the structural analysis of piping systems (aka, “piping flexibility and stress analysis”). These methods were the easiest ways to perform piping structural analyses before computers became generally available (circa, 1960 or so). While these methods were useful at one time, computer analysis is now the accepted methodology and the “approximate methods” are of academic interest only.
First.
You must recognize that the structural analysis of piping systems is tied to various sets of Codes and Standards. You have to determine what Codes and Standards are mandated by the jurisdiction in which the piping system you are to design will be located. Then you must simply sit down and read the Codes and Standards mandated by that jurisdiction – the cited books will help by providing some of the background for the rules you see in the C&S’s.
The ASME B31 Pressure Piping Codes include fatigue rules that came from basic testing in the late ‘40’s and early ‘50’s. The transition from testing results to Code rules was explained in classic papers written by Arthur R.C. Markl. You may be able to find a used copy of the old book, “Design of Piping Systems”, printed by Tube Turns Company, to get the fundamental background of the methodologies of the B31 Pressure Piping Codes. This book included the five classic ASME papers written by Arthur R. C. Markl (with a lot of help from his colleagues). These papers were originally published (circa 1951 - 1955) in an old hardbound (Blue) book by ASME ("the Blue Bible") but were subsequently published by Markl's employer, Tube Turns Company, in their book, "Design of Piping Systems" (out of print of course).
Second.
When working with pressure technology Codes and Standards, it is useful to be comfortable with the various methods used by the various Codes to combine stresses (Rankine, Tresca and Von Mises failure criteria). Review the fundamentals of beam theory structural analysis. Go back into your introduction to mechanics and strength of materials book and look at Mohr’s circles of stress and review the concept of unit cubes and how stresses are combined.
And have a look at:
http://feaservices.com/fund_struct/fund_struct.html#General%203-D%20Stress%20State Also, if you want to get a rigorous explanation of the methods and mathematics of structural analysis of piping systems look for:
Piping Handbook, FIFTH EDITION, by Sabin Crocker and Reno C. King (look on the Internet for used books), there is a lengthy and excellent chapter that was prepared by John Brock that gives you a good background. The excellent seventh edition of this book is the current edition, but the chapter at issue was dropped after the fifth edition.
The other classic for looking at the math and methods is “Principles of Piping Analysis”, by David Burgreen, 1977, C-P Press, ISBN 0960045228. You will have to search the used book market for this one also.
Third.
The ASME B31 Pressure Piping Codes are based upon beam theory (albeit they do not preclude other valid methodologies) and the software for piping structural analyses are based upon beam theory. Learn about the beam theory method of analysis of structural SYSTEMS. Focus upon the distribution of forces and moments over the SYSTEM. Review the loadings on the system (weight (dead weight and live weight), wind, thermal expansion thrusts, seismic excitation, etc.) and the load paths that take these loadings to the boundary fixtures (anchors, hangers, supports, rotating equipment and non-rotating equipment (vessels, heat exchangers, etc)). Learn the secrets of the artful science of pipe hanger design. Look at this (thanks Foglamp):
http://www.anvilintl.com/db/datasheets/Pipe_Hanger_Design-05.pdf The B31 Code (MDC) is close to issuing a guide (B31-E) for seismic design of piping systems (and restraints), but in the interim this might be of interest to you:
http://www.americanlifelinesalliance.org/pdf/Seismic_Design_and_Retrofit_of_Piping_Systems.pdf Now remember that this is all based upon beam theory and in some cases beam theory will not predict the highest stresses that will be developed in some pipe system components. So you must understand the limits of beam theory and learn about methods (typically finite element method) for modeling individual components and applying forces and moments from your beam theory analysis to your FEA model.
Learn about the strain sensitivity of the equipment to which piping systems are frequently attached (rotating equipment and non-rotating equipment). Study the Standards that set the limits for the amount of loading (forces and moments) that may be safely transferred to this equipment by the piping.
Fourth
Look at the availability of computer structural analysis software and choose the best software that you can get. After you have installed Caesar II, learn everything that you can about the program. The most time effective thing you can do is go to the COADE, Caesar II training. Read ALL the manuals that you will get with Caesar II (that is a LOT of reading). I have found that most of the (less than "good") questions that have come to my mind have been addressed in these manuals (I have actually developed a taste for "eating crow"). There is a LOT of good help to be found for improving your modeling techniques in the
CAESAR II manuals.
At this point, this also might interest you:
http://www.pipingdesigners.com/downloads/process%20plant%20piping%20overview.pdf Fifth
It is important to know where you can go to ask good questions. The sources of information cited above will serve you well for about 70 percent of the piping systems that you are called upon to design. There are many “except for's” in piping design. You will learn techniques for the analysis of buried systems, double containment piping systems, non-metalic piping systems (plastic, glass, etc.), very large diameter (relatively thin wall) piping systems, systems with “strap-on” heating jackets and …….well you get the picture. But the good news is that the community of piping engineers is rich in advice and in most cases quite approachable.
Learn where to go to ask good questions of the community. First, do your homework and try to find answers to your questions using your own intelligence. Learn how to frame a good question unambiguously and find forums where you can ask your “good questions” (be prepared for the occasional “put down” by some egocentric self styled “expert” who is so unsure of himself that he must degrade others to elevate his own sense of self importance – it comes with the territory). Visit the forums even when you do not have a question as there will be questions asked there that you may not have thought of. Learn how to use the search function provided by the forum – it is likely that your question may have been asked before.
If you follow this path you will only need to add years of actual experience to become a piping engineer who is competent in the static structural analysis of linear elastic piping systems. Then you will be motivated to learn about dynamic analyses and inelastic non-linear systems.
Regards, John.
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