What is the difference between SCH40 and SCH40S?

[braham0793]

I wonder if the only difference would be just thick.?

It happens that the thickness of the spool at one point and according to the BOM of the plane tells me SCH40 and elsewhere indicates that I should be SCH40S, would I use the tube in place at SCH40 SCH40.

Best regards

 

[XL83NL]

Your answer lies in the difference between ASME B36.10 and ASME B36.19.
In general, I believe the -S designator arises from the .19 standard which used to be for stainless pipe. At (i.e. above) certain sizes, Sch40 and Sch40S are not the same anymore. Hence the need to spec if youre using B36.10 or B36.19.

 

[LittleInch]

Its a bit odd but depends on pipe size. Up to 10 inch they appear to be the same, but 12" and above it ask hours a bit haywire.

The S usually signifies stainless Standard sizes, especially 10S which is not normally made in carbon steel.

https://en.m.wikipedia.org/wiki/Nominal_Pipe_Size

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[racookpe1978]

I have always treated 10s, 5s, or 40s as stainless schedules, but have found nothing previously in the books and pipe tables to contradict it.

Is that a bad assumption?

 

[BigInch]

It is exactly that, to designate stainless steel pipe dimensions. S walls may be equal, but are typically thinner than CS walls. Perhaps because stainless is more expensive and was a bit stronger than the early carbon steels.