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Hotwired
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Tue Jan 08, 2008 4:55 pm

MrCrowley wrote: e.g 50mm pressure pipe has a real I.D Of around 65mm.
How in the name of a possibly existing deity is a 50mm pipe having an internal diameter of 65mm.

In the country I hang out in, there are pressure pipes made of PVC and they can be found in metric. On this page of a supplier is a dimensions table (halfway down).

For a 65mm ID you would need a 75mm OD pipe.

A 50mm pipe has a 40mm bore.
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MrCrowley
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Tue Jan 08, 2008 5:03 pm

Hotwired wrote:
MrCrowley wrote: e.g 50mm pressure pipe has a real I.D Of around 65mm.
How in the name of a possibly existing deity is a 50mm pipe having an internal diameter of 65mm.

In the country I hang out in, there are pressure pipes made of PVC and they can be found in metric. On this page of a supplier is a dimensions table (halfway down).

For a 65mm ID you would need a 75mm OD pipe.

A 50mm pipe has a 40mm bore.
It might be the O.D, argh screw it i'll go and check.

Ok, I.D is 55mm not 65mm, O.D is 61-ish mm.

There is no way 50mm pressure pipe has an I.D of 40mm, otherwise GOLFBALLS WOULDN'T FIT INSIDE THE PIPE AS THEY HAVE A DIAMETER OF 44MM

50mm is the nominal diameter, the 65mm I.D I said is from DWV pipe I think, as I said it's I.D is actually 55mm.

NOT 40mm!
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Hotwired
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Tue Jan 08, 2008 5:25 pm

It's your whacky pipe system and you know it :P

Your daft stuff is in the schedule system and the UK system for plastic pressure pipe is the class system (class C, D, E, T).

Mystery solved.

Of course the one I was interested in was the magical ID larger than the OD :wink:
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ALIHISGREAT
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Tue Jan 08, 2008 5:42 pm

Hotwired wrote:It's your whacky pipe system and you know it :P

Your daft stuff is in the schedule system and the UK system for plastic pressure pipe is the class system (class C, D, E, T).

Mystery solved.

Of course the one I was interested in was the magical ID larger than the OD :wink:
the two systems are completly different? the schedule system works on wall thickness and our class system on pressure rating right?

i wish we had the schedule system, it would mean crazy 400psi rated 1" pvc :D
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MrCrowley
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Tue Jan 08, 2008 5:48 pm

Hotwired wrote:It's your whacky pipe system and you know it :P

Your daft stuff is in the schedule system and the UK system for plastic pressure pipe is the class system (class C, D, E, T).

Mystery solved.

Of course the one I was interested in was the magical ID larger than the OD :wink:
We used to use the class system, A-F I think it was, you can still find the odd pipe in the class section but we don't use the schedule system either.

The AS/NZS (Aussie/NZ standards) are the PN system, also found in Europe.

So we have a mixture of class, schedule and PN system here, whereas the schedule system is sometimes found on smaller fittings that have been imported from the States, class system from a few years ago, and the now current PN system.

The PN system has very similar dimensions to the schedule system, all your pipe and fittings work with it. Only difference i've noticed is their 1.5" pressure pipe has a small I.D then our 40mm pressure pipe but both have the same O.D.

That's why we have so much golfball barrel pipe, because 40mm is very common, yet in America you need SDR21 pipe.

And 50mm pipe still has a larger I.D(55mm) then it's nominal diameter(50mm).
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Hotwired
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Tue Jan 08, 2008 5:56 pm

When I say 50mm pipe... I mean it's pipe with an OD of 50mm and an ID of 40mm.

I can't help thinking you're meaning exactly the opposite.

Another attack of the whacky pipe system?
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MrCrowley
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Tue Jan 08, 2008 6:15 pm

Well I mean the nominal diameter, the number written on the pipe.

Are you talking about PVC?

Well the number written on the pipe, is the nominal diameter.

How can you base of the real diameter? Don't you have to lug around a caliper everywhere?

Is there even pipe with those dimensions? I know 40mm nominal diameter pipe as an I.D of 45mm, and th next size down 32mm nominal diameter pipe can't possibly have an O.D of 50mm.

Why don't you just go by whats on the pipe and price tag?
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TwitchTheAussie
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Wed Jan 09, 2008 2:04 am

Well 1/2 sch80 no matter what does NOT fit standard marbles.
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Hotwired
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Wed Jan 09, 2008 3:42 am

MrCrowley wrote:Well I mean the nominal diameter, the number written on the pipe.

Why don't you just go by whats on the pipe and price tag?
Thats exactly my point...

Pipe IS sold here by the OD :roll:

Except for Imperial pipe which goes by the ID in inches.

But Metric pipe, you're given the OD and as shown in the dimensions table above I don't need a pair of calipers to find the ID.

I could have said the same thing as the pipe you get seems to not actually be the ID given. Give or take 5mm is a vernier caliper job :P
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MrCrowley
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Wed Jan 09, 2008 3:54 am

Weird, well if you ever venture down to NZ or Aus, pipe is not what you think it is :lol:

In America it's labelled as the nominal diameter too, so maybe it's the UK that has the problem :wink:
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TwitchTheAussie
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Thu Jan 10, 2008 12:02 am

Anyone else got any ideas on what size pipe will fit a marble 16mm. Its under imperial system in home hardware so ideas are welcome.
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