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14" stainless steel pipe thickness 2

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jtseng123

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Jun 6, 2012
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My supplier proposed 14"- Sch "80S", 304H stainless steel pipe.
There is no such Sch "80S" for 14" pipe.
My interpretation is 0.75" thick wall, just like 14" Sch 80,
My supplier said it is 1/2" thick wall, just like 14" X-Stg.
Who is right ?
 
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If 14" sch 80s is 1/2" thick pipe, what will be the thickness for 14"-Sch 60 stainless steel pipe ?
I am not quite underatnding the logic for stainless steel pipe wall thickness.
I was told that if you can not find a schedule that comes with "S" for stainless steel, then shcedule without "S" is the thckness to be used.
 
In reality, it can be produced without problem. Pipe thickness has 3 designations : "carbon and alloy steels", "stainless steels", and " weight".
I believe "carbon and alloy steels" can also cover stainless steel if there is no "stainless steel" schedule with "S" available on the table.
That is the way our company and other suppliers interpret it until now the specific supplier telling me differently.


 
Guys,
I am a bit confused so please bear with my questions.
ANSI/ASME B36-10 - Welded and Seamless Wrought Steel Pipe has no mention of Sch 80s (or any Sch ..s)
ANSI/ASME B36-19 - Stainless Steel Pipe has Sch 40s and Sch 80s only up to 12" - there is no 14" and above Sch 40s or Sch 80s.

Tried google and found Atlas Steels Product Range.
Stainless Steel Pipe - Welded and Seamless - ASTM A312M.
This product range lists 350 nb Sch 80s as 12.7 mm WT.

So I go to ASTM A312M and there is no Sch 40s or Sch 80s for diameters greater than 12".

Do these pipes not have to be manufactured in accordance with a specific standard ?
Cheers,
Kiwi
 
The roots of the pipe schedule problem go back to the 1880's
It was intended that ASME would drop the schedule designations in the 1940s, but some people still persist in trying to use them.
You should not.

Call out your pipe using Outside diameter, wall thickness and weight per unit length.
4000 FT, PIPE, 12.75" OD x 0.500 WT @ 65.42 lbs/ft, ASTM A106-B

Schedule 80 S=>for Stainless Steel) is 0.500" (12.7 mm) wall thickness.
Carbon Steel Pipe Schedule 80 is 0.750" wall thickness.

See ASTM A358 for larger sizes of stainless pipe.



If it ain't broke, don't fix it. If it's not safe ... make it that way.
 
I think the supplier is basing his sizing on the fact that all the way up to NPS 12, Sch 80S is the same as Sch XS rather than being the same as Sch 80. He is extrapolating this and then assuming that for NPS 14 pipe, Sch 80S would be the same as Sch XS (which is 0.500" thick).

Note: Sch 40S is the same as Sch Std all the way up to NPS 12 rather than being the same as Sch 40.

In the Pipeline Industry, there has been movement towards using actual wall thickness values as mentioned by BigInch but in plant piping, the industry pretty much universally still refers to pipe by schedules.

 
With pipeline pipe we can often make a mill order to an exact wall thickness requirement, so there aren't any schedules to refer to in that case.

If it ain't broke, don't fix it. If it's not safe ... make it that way.
 
Conclusion:
Many of your handbooks, just like mine, do not have Sch 80S for 14" and above. Indeed, Sch 80S is 1/2" thick for 14" and above, as in the website given by Stanier's reply. Please go to that website and check it out.
My supplier is right.
 
Guys,
My comments above were based on the B36.10 and B36.19 standards that I had available (obviously superceded).
The link that Stanier posted lists 2004 editions as reference material and I was looking at 1996 editions.
Does anyone have 2004 editions of these standards ?
Has Sch 80s been added to these later editions ?
Cheers,
Kiwi
 
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