Piping classes origin
Piping classes origin
(OP)
Hello everybody!
First, I introduce myself: I'm a novice process engineer working on a gas company since soon 3 months...
I used to ask my questions on chemical process engineering forum.
I would like to ask a new question about "piping classes origin", I have found an interesting discussion here about this topic...(thread378-123846: Piping Classes Origin ? )
I would like to know why they have choose exactly these numbers: 150, 300, 400...etc...and not 200, 350... for example?
Someone spoke about the pressures in psig at the corresponding saturated steam temperature, do you know more??
(I apologize for my bad English, I am French...)
Thanks a lot!
Méli





RE: Piping classes origin
Like the ASME flange classes which is what you are quoting, there was good reason a long time back, and why change it now. I suspect that the classes resulted from developing work in the American steam locomotive or stationary boiler industry. It's not UK based ... not our fault !!
You might note that EN pressure standards follow pretty much the same categories with PN 50, PN 250, PN 420 etc.
RE: Piping classes origin
I though there is a same nice story for classes pinping...
(Sorry again for my English
Méli
RE: Piping classes origin
(BTW, just turn it around, EN: Geometric progression" and again, ES: progresión geometrica)
"Make everything as simple as possible, but not simpler." - Albert Einstein (1879-1955)
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RE: Piping classes origin
"Why do they call it a Flange?"
Flange
(From Wikipedia, the free encyclopedia)
A flange is an external or internal rib, or rim (lip), for strength, as the flange of an iron beam or I-beam (or a T-beam); or for a guide, as the flange of a train wheel; or for attachment to another object, as the flange on the end of a pipe, steam cylinder, etc, or on the lens mount of a camera. Thus a flanged rail is a rail with a flange on one side to keep wheels, etc., from running off. The term "flange" is also used for a kind of tool used to form flanges.
RE: Piping classes origin
"Make everything as simple as possible, but not simpler." - Albert Einstein (1879-1955)
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RE: Piping classes origin
I just like to understand the origin of things.
Méli
RE: Piping classes origin
"Make everything as simple as possible, but not simpler." - Albert Einstein (1879-1955)
***************
http://virtualpipeline.spaces.live.com/
RE: Piping classes origin
RE: Piping classes origin
"Make everything as simple as possible, but not simpler." - Albert Einstein (1879-1955)
***************
http://virtualpipeline.spaces.live.com/
RE: Piping classes origin
As to the origins of the NPS pipe sizes and selected ANSI flange classes, I have no idea. It's really a good question in the Engineering History thread- bet there's somebody out there who knows!
RE: Piping classes origin
http://en.wikipedia.org/wiki/Nominal_Pipe_Size
It appears that it was a standardization approach that started out with good intentions, but went awry in an attempt to keep consistent with pre-existing iron pipe sizes and wall thicknesses currently in use at the time the standard was being developed. The standard-writers' attempt to provide backward compatibility is the reason we've ended up with a system which appears to have no consistent basis- until you're at 14" at which point at least all schedules have the same OD.
Analogous to the old gem about the gauge of the railway tracks being based on the width of two horses' @sses!
RE: Piping classes origin
Perhaps the individual gauge selection depended upon the breed of the horses.
As with B16.5 for flange classes, the forward of ASME B36.10 provides some insight. The pipe schedule numbers related to ratios associated with Barlow formula for pipe thickness.
RE: Piping classes origin
All schedules have the same OD, no matter what diameter they are for.
"Make everything as simple as possible, but not simpler." - Albert Einstein (1879-1955)
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http://virtualpipeline.spaces.live.com/
RE: Piping classes origin
What I MEANT to say was 14" plus has an OD equal to the nominal size...
RE: Piping classes origin
RE: Piping classes origin
I'm not saying thats the basis, but its an interest trend.