What Happened to Schedule 40, 80 & "-" Pipe?
What Happened to Schedule 40, 80 & "-" Pipe?
(OP)
This is nothing more than an (semi-rhetorical) inquiry and, perhaps, history lesson(ette).
What happened to Schedule 40, 80 & "-" Pipe?
"Std" = Standard = Schedule 40. "XS" = Extra-Strong = Schedule 80. "XXS" = Double-Extra Strong = Schedule "-".
Why is XXS = Schedule "-"? Why didn't XXS get a "Schedule" designation?
What does "40" and "80" mean?
Sometime after AISC 9th, while still maintaining the "Pipe" designation, the industry introduced "Round HSS" which provided some "more economical" thinner walls than the 0.322" wall of "Std".
I'm just curious as to when, how, why the "schedule" designation evolved, what was its' purpose and intent, and why it was discontinued?
I notice that PEMB (Pre-Engineered Metal Building) Industry makes great us of the thinner wall HSS. Did they have influence to the use of either "Pipe", "Schedules" or "HSS Round"?
Is there a benefit, pro or con specifying "Pipe" versus "HSS Round"?
Is this an appropriate category to post this? I've considered posting this in "Where is Engineering Going..." but, should we consider a new category of "Where has Engineering Been?"
Thank you!
What happened to Schedule 40, 80 & "-" Pipe?
"Std" = Standard = Schedule 40. "XS" = Extra-Strong = Schedule 80. "XXS" = Double-Extra Strong = Schedule "-".
Why is XXS = Schedule "-"? Why didn't XXS get a "Schedule" designation?
What does "40" and "80" mean?
Sometime after AISC 9th, while still maintaining the "Pipe" designation, the industry introduced "Round HSS" which provided some "more economical" thinner walls than the 0.322" wall of "Std".
I'm just curious as to when, how, why the "schedule" designation evolved, what was its' purpose and intent, and why it was discontinued?
I notice that PEMB (Pre-Engineered Metal Building) Industry makes great us of the thinner wall HSS. Did they have influence to the use of either "Pipe", "Schedules" or "HSS Round"?
Is there a benefit, pro or con specifying "Pipe" versus "HSS Round"?
Is this an appropriate category to post this? I've considered posting this in "Where is Engineering Going..." but, should we consider a new category of "Where has Engineering Been?"
Thank you!






RE: What Happened to Schedule 40, 80 & "-" Pipe?
RE: What Happened to Schedule 40, 80 & "-" Pipe?
I do know (most) of the rebar size logic:
#2 through #8 = Bar diameter in eighths of an inch.
#9 = Old 1" square rebar size = diameter set so that nominal area is 1.00 in2
#10 = Old 1 1/8" square rebar size = diameter set so that nominal area is 1.27 in2
#11 = Old 1 1/4" square rebar size = diameter set so that nominal area is 1.56 in2
#14 = Old 1 1/2" square rebar size = diameter set so that nominal area is 2.25 in2
#18 = Old 2" square rebar size = diameter set so that nominal area is 4.00 in2
www.SlideRuleEra.net
www.VacuumTubeEra.net
RE: What Happened to Schedule 40, 80 & "-" Pipe?
Noted that there are only some pipe sizes with Std pipe = SCH.40 and XS pipe = Sch.80, not for all sizes.
RE: What Happened to Schedule 40, 80 & "-" Pipe?
Schedule pipe is still a thing. It's just not what the steel handbook calls up, and we've introduced structural HSS tube that's more appropriate for our uses. Tolerances are different, materials are different and dimensions are different. Pressure pipe and structural HSS are trying to do different things, so now we've got products that target the specific applications.