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    under size steam header (15 Posts)

  • dwh54 dwh54 @ 10:03 PM
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    under size steam header

    what will happen when you under size your boiler header have a boiler with 2 5inch risers off of boiler they go into a 6inch header boiler manufacure wants a 8inch header
  • Steamhead Steamhead @ 11:03 PM
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    You'll have a LOT of problems

    wet steam, high fuel consumption, uneven heat, banging, water-level problems in the boiler........

    Do it right. Change the header.
    "Reducing our country's energy consumption, one system at a time"

    Steam, Vapor & Hot-Water Heating Specialists

    Oil & Gas Burner Service

    Baltimore, MD (USA) and consulting anywhere.
  • pipeking pipeking @ 11:47 AM
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    u got to do what the manuf. want if u ever have problems down the road, but 8" does seem excessive. 2- 2.5" pipes don't even come close to 1- 6" flow rate, so what is it based on?
  • MTC MTC @ 9:54 PM
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    That's 2) 5" risers,

    which makes sense for an 8" header. Must be a pretty large building...
  • Charlie from wmass Charlie from wmass @ 10:11 PM
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    wet steam poor heat

    2.5 x2.5x 3.1416x2 = 39.27
    3x3x3.1416= 28.27
    You need the 8" header.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • MTC MTC @ 10:23 PM
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    I agree with your conclusion Charlie,

    but not sure I understand what you mean by your math. Can you explain further please?
  • pipeking pipeking @ 11:18 PM
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    yes charlie please explain...

    this is my math, if i'm wrong i need to know where
    the radius of a 2.5" pipe is 1.25"          and the radius of a 6"pipe is 3"
    1.25x1.25x3.14=4.90sqin +                        3x3x3.14=28.26sqin
                       = 9.8sqin
    i can't get it to stop underlining!!!   but i'm pretty sure that u add the area off the two 2.5" risers to get the tottal area of the two, but if i'm wrong and you multiply them together it's still only 24.01sqin.
  • Charlie from wmass Charlie from wmass @ 12:28 AM
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    it is two 5" risers pipeking not

    two 2 1/2" risers. we are in the big leagues now boys.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • MTC MTC @ 11:37 PM
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    Oh, I think I get what you're saying Charlie...

    The area of (2) 5" risers is Pi*Rsquared = 3.14*2.5squared, times 2 risers = 39.27

    The area of the current 6" header is PiRsquared = 3.14*3squared = 28.27, which is too small

    The area of the spec'd 8" header is PiRsquared = 3.14*4squared = 50.26, which is larger than the total area of the 2 5" risers.

    The minimum header size would be slightly larger than 7", which means you need an 8" header.
  • SWEI SWEI @ 1:18 AM
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    and you can drop the π

    anytime you are comparing round pipes.  Squaring either D or R will give you the answer.
  • Charlie from wmass Charlie from wmass @ 8:24 AM
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    I kept in Pi to show

    the actual area diffrence not ust the proportional  difference. If the numbers differ by larger amounts it seems to make the problem more visible. When comparing in my head I leave out the Pi. Unless it is right after supper then I have the pie if it is there to be had.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • MTC MTC @ 10:51 AM
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    Good point...

    multiplying all variables by the same constant does just give you more messy math. I hadn't really ever thought about it.

    I'm kind of anal though, and I think seeing the real numbers, not just proportional numbers, somehow makes me happier, whatever that means.

    What about pi FOR dinner?
  • Charlie from wmass Charlie from wmass @ 1:06 PM
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    Pie for dinner

    Pot pie or Steak and Kidney? The kidney in steak and kidney pie is beef kidney not kidney beans so you should be good.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    This post was edited by an admin on February 16, 2013 10:54 AM.
  • MTC MTC @ 5:12 PM
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    can't do kidney beans... but pot pie is all good :)
  • pipeking pipeking @ 9:55 AM
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     i could have swore it said " how would u size a boiler with 2.5inch risers" i thought there was a decimal point.!! you got it, whoaoawhoa, you got it!! we're in the big leagues now!
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