Steel specifications

[Damaged]

Hi all,

Could anybody please explain the "shed" rating of steel please? (that is very probably spelt wrong), was ordering a replacement machine roll today and was asked if I wanted "shed 10 or shed 40"

Never heard of this before so any explanation would be greatly appreciated.

Many Thanks,

Mick.

 

[Hitch]

What sort of machine Mick? Is it weaving...? I have a vague recall about the mention shed rolers when i was doing a bit at a fibreglass factory.....

I havnt got a clue otherwise to be honest.

 

[Paul.]

I think you might mean Sched, short for schedule which refers the wall thickness of pipe lower the number, thinner the pipe.

 

[Damaged]

Hi Hitch,

It's a paper machine, rollers are 3.5 Mtrs wide and runs at around 1400 Mtrs / Min.

I usualy only have to spec the grade of S.S. but didn't want to admit my ignorance of the "shed" rating, I got the feel that it was something to do with how much the roll would deflect for a given load but I may well be wrong.

Mick.

 

[Damaged]

Ah!

Thanks Paul,

You posted that whilst I was typing the reply to Hitch's post.

That would make sense, I've heard of "Schedule" just didn't relate it to "shed"

Mick.

 

[Paul.]

what diameter are the rollers Mick?

 

[gavuk]

i agree with paul schedule not shed ,are they hollow rollers,steam heated by chance? gav

 

[Hitch]

Ah, Schedule, heard of it, but couldnt tell you anything.

Well done Paul

 

[gavuk]

http://www.tubenet.org.uk/specs/asmsched160.html
http://www.tubenet.org.uk/specs/asmesched40.html

 

[Damaged]

Cheers Gents,

The roll in question is approx 18" diameter as it's only a path roll, the largest diameter roll (the forming roll) is around 4' in diameter.

Is there a formulae to calculate the schedule taking into account the width, diameter and load?

Mick.

 

[gavuk]

I'll let paul answer that question more to do with pressure rating than load i think .............
http://www.engineeringtoolbox.com/steel-pipes-dimensions-d_43.html

 

[Paul.]

you beat me to it Gavuk,
for mechanical loadings rather than pressure, I would calculate as if it were a beam, it could get quite involved though being a roller, you have to consider reciprocating loading on the roller, rpm, temperature, internal pressure (if any) design and position of any internal supports or bearings, I used to design and build machinery for the corrugated board industry, nowhere near as big as these rollers though, but same principles apply.

 

[gavuk]

ha ha paul i used to be a fitter in corrugating factory,thats why i asked if they were steam heated like a conditioning or fluteing roller......

 

[Paul.]

My stuff was mainly aimed at the box makers, cutting and creasing, folding and gluing,

 

[Damaged]

Thanks gents,

It's only a path roller so internal pressure isn't an issue.

As sugested I'll base the calc's on a beam.

Many thanks for your help.