General Pipework Question

[Leoki]

Hello, i hope that someone can help me please, i am getting a bit mixed up with pipework sizes and the different methods of measuring. As much as i do understand is that copper pipework is measured from the outer diameter, plastic pipework such as ABS for wastepipes is measured from the inner diameter but on some work that i have to do with some 3/4 galvanised steel pipework terms of reference are a bit confusing. I think i am getting confused/bogged with with Nominal pipe sizes. I have a chart for example that lists 3/4 inch steel pipework. If you read the line entry across on the chart it has nominal pipe size 20mm or 3/4 inch, outside diameter 26.7mm but it goes on to read major diameter in inches 1.041 and minor diameter in inches 0.949.

Can i confirm that steel pipework is measured from the inner diameter ?

Can anyone recommend a book/publication or a website that i good go too that i could use to help me understand better.

 

[Joncpi]

Yes I can confirm steel pipe is measured by its inside diameter. As for a book/publication sorry I can't help. Steel pipe being measured internally is something that was taught to me many years ago.

 

[PlumbBobBob]

leoki if you go to the plumbers forum in the stickies at the top there is a post by dave entitled books for plumbers you should be able to find something in there.

 

[Leoki]

Thankyou for the replies in particular steveb for your pointer towards Daves bit on books. I have just ordered Treloars 4th edition from Amazon, you can get it on offer at the moment including free p & p for £19.99. I have an earlier book by Treloar until i checked though via Daves links i just did not realise he has updated it. Thankyou again.

 

[tipintim]

Sorry, wronge thread some how

 

[PlumbBobBob]

you're welcome

 

[adam84]

British standards online will has a whole page/section dedicated to current and obsolete pipe sizes and methods of establishing pipe sizes, though im not sure if this information is down loadable.