Steam Distribution Piping
Steam Distribution Piping
(OP)
I would like your support for the following problem:
My two questions are regarding aboveground outdoor steam distribution piping approximately 2km in length. Pressure is 17.5bar.
1. Between B31.3 and B31.1, which one will be the best design code?
2. In pressure loss calculation, crane fluid book are employed. In this process, I did not find any procedure to consider the condensation of steam and its resulting positive pressure driven force. Could you advise me related method we can employ regarding this to make the piping sizing a little less conservative?
I searched this wonderful forum and could not find specific answers.
Any comments are appreciated. Thanks.
My two questions are regarding aboveground outdoor steam distribution piping approximately 2km in length. Pressure is 17.5bar.
1. Between B31.3 and B31.1, which one will be the best design code?
2. In pressure loss calculation, crane fluid book are employed. In this process, I did not find any procedure to consider the condensation of steam and its resulting positive pressure driven force. Could you advise me related method we can employ regarding this to make the piping sizing a little less conservative?
I searched this wonderful forum and could not find specific answers.
Any comments are appreciated. Thanks.





RE: Steam Distribution Piping
B31.1 Power Piping: piping typically found in electric power generating stations, in industrial and
institutional plants, geothermal heating systems, and district heating and cooling systems. B31.1 has
requirements for
• Piping for steam, water, oil, gas, air and other fluids
• Metallic and nonmetallic piping
• All pressures
• Temperatures greater than -29ºC (-20ºF)
There may be local juristictional legal requirements you need to look into, they more will than likely invoke B31.1 for steam at the pressure you listed.
As to you second question we use the crane values.
Always remember, free advice is worth exactly what you pay for it!
RE: Steam Distribution Piping
Katmar Software
Engineering & Risk Analysis Software
http://katmarsoftware.com
RE: Steam Distribution Piping
RE: Steam Distribution Piping
http://
Further to condensate, Katmar got the point: be sure your line is fitted with enough steam traps and adequate drainage.
RE: Steam Distribution Piping
Have a look at the link you posted and what the Codes cover. B31.1 "Boiler external pipework" and B31.3 steam is listed in the piping systems covered. Steam distribution systems are not "Boiler External piping" hence B31.3 is the more logical choice.
RE: Steam Distribution Piping
http://www.kirsner.org/pages/training.html
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"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/
RE: Steam Distribution Piping
Well, it was obviously just my opinion, but since ASME B 31.1 does not apply to:
• economizers, heaters, pressure vessels, and components covered by Sections of the ASME Boiler and Pressure Vessel Code;
• building heating and distribution steam and condensate piping designed for 15 psig [100 kPa(gage)] or less, or hot water heating systems designed for 30 psig [200 kPa (gage)] or less;
• piping for hydraulic or pneumatic tools and their components downstream of the first block or stop valve off the system distribution header;
• piping for marine or other installations under Federal control;
• towers, building frames, tanks, mechanical equipment, instruments, and foundations.
And we are talking about a pipeline with steam at 17.5 barg (approx 254 psig), I do not seen any violation of the code.
Moreover
B31.1 Power Piping: piping typically found in electric power generating stations, in industrial and institutional plants, geothermal heating systems, and district heating and cooling systems. B31.1 has
requirements for
• Piping for steam, water, oil, gas, air and other fluids
• Metallic and nonmetallic piping
• All pressures
• Temperatures greater than -29ºC (-20ºF)
B31.3 Process Piping: piping typically found in petroleum refineries, chemical, pharmaceutical, textile, paper, semiconductor, and cryogenic plants, and related processing plants and terminals. B31.3 has requirements for
• Piping for all fluid services
• Metallic and nonmetallic piping
• All pressures
• All temperatures
I have never stated "You must use B 31.1". Both B 31.1 and B31.3 should be suitable. You probably prefer B 31.3 as by your own admission have dealt with petrochemical plants, where B 31.3 finds a wide application.
RE: Steam Distribution Piping
**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/
RE: Steam Distribution Piping
Appologies as I obviously hit a raw nerve.
RE: Steam Distribution Piping
RE: Steam Distribution Piping
Efficient Use of Steam Oliver Lyle
Steam Trapping and Venting Northcott & Barber
These were the bibles 35 years ago. Steam has not changed much in that time.
I find it strange that you have used an SI unit for pressure yet refer to ASME B31.1. Are you in the USA? Is there perhaps a local standard you should be using? Just curious.
RE: Steam Distribution Piping
RE: Steam Distribution Piping
**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/
RE: Steam Distribution Piping
Software that you have no control over tends to lead to a state of apathy, n'est ce pas?
RE: Steam Distribution Piping
(Hasn't affected me in previous work, since all of my traps and drains, condensate, cooling etc have inside a single plant. Just being curious about traps in the great outdoors where I would be unable to control "floor level" of the drain system.)
RE: Steam Distribution Piping
RE: Steam Distribution Piping
Condensate collected from steam distribution systems is frequently not recovered due to the expense of the return piping system.
Condensate collection from steam piping systems going uphill and downhill is not a problem if steam is collected in short drip/drainlegs as has been done for eons...
htt
It is also a good idea to generate steam with a little bit of superheat in long distribution systems to decrease the production of condensate.
My opinion only...
-MJC
RE: Steam Distribution Piping
Now for condensate removal from steam headers, they're called drip legs which hookup to continous drainers, condensate pumps, flash tanks, steam traps, etc. All depending on condensate load and what one is trying to do with the condensate. As for the installation and location of drip legs, that is dependent on cond.load and Header layouts.
For a full blown analysis of the problems and solutions of condensate removal, see the Armstrong Machine Works site and above all contact a rep..