Pipes and tubes: is the difference still taught?

[Syncopator]

Many decades ago, at about the time I acquired my first pair of long trousers, a cousin started work in one of the then most prestigious boilermakers in the U.K. (

http://www.localhistory.scit.wlv.ac.uk/Museum/Engineering/JohnThompson/johnthompson00.htm#menu)

After he had worked there for a while he was taught the difference between a pipe and a tube and asked me if I knew. No. So he told me.

I forget which is which now, but the difference is that one is rolled and therefore has a seam, while the other is drawn or extruded and therefore does not have a seam.

I have seen the question posted elsewhere and it attracted many answers, none of them in accordance with the above and most of them totally illogical and based on common (mis) use.

So, is the proper distinction no longer taught?



Equal rights for equal responsibilities.
Equal opportunities for equal abilities.

 

[Syncopator]

In view of the fact that there are several definitions in use, particularly in the 'States, it would be interesting, although no doubt impossible, to look at the schooling/training/learning which the people responsible for these definitions received.

I have found similar discrepancies in what people believe within my own discipline, electronics. I believe it all stems from incompetent and incomplete teaching, and lacadaisical learning. The biggest problem is that once one "learns" something, or comes to believe it, it is difficult or impossible to get the believer to consider any other explanation.



Equal rights for equal responsibilities.
Equal opportunities for equal abilities.

 

[CarlB]

I've got nothing to add, other than I've seen this discussed several times before. Could only find these 2 offhand...
thread378-213369 March 08
thread378-118821 March 05

 

[GregLocock]

Well by usage in cars, things that carry fluids that are attached to hoses are often called lines, brake pipes are about the only ones that are called pipes commonly, but brake lines is fine as well.

Tubes are used to make spaceframes.

I don't know what the heat exchanger boys routinely use, they have their own weird terminology (do you know what a register and a regulator are in a car?).



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[Bobber1]

And in the US, electrical metallic tubing (emt, or electrical conduit) is also called schedule 10 pipe.

The American Institute of Steel Construction (AISC) in their latest manual ties down pipe vs. tube, but this is more from a structural standpoint.

 

[btrueblood]

Greg,

What about the tail pipe?

 

[KENAT]

Maybe it's in the same class that they teach the difference between a screw & a bolt.

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[drawoh]

btrueblood,

What about named pipes?

It is apparent that the people who write the Machinery's Handbook and all of our catalogues, were not taught the difference between pipes and tubes. How about, it is a pipe if I @#$%^& well call it a *^%$*(# pipe?

JHG

 

[Hydromechdude]

I've always thought that tubing had a constant OD with changing wall thickness, depending upon pressure, material, etc. The best example I can think of is copper tubing for plumbing, which has the same OD as the tube name. A half inch tube has a .5" OD.

I haven't worked with any piping, but from what I recall in university, I thought the difference was that piping did not have an OD equal to the name of the pipe.

 

[ColonelSanders83]

Gentleman,

According to ASME B36.10M "Welded and Seamless Wrought Steel Pipe"

1 SCOPE " The word PIPE is used, as distinguished from TUBE, to apply to tubular products of dimensions commonly used for pipeline and piping systems. Pipe NPS 12 (DN 300) and smaller have outside diameters numerically larger than their corresponding sizes. In contrast the outside diameters of tubes are numerically identical to the size number for all sizes"

Just my two cents worth.

A question properly stated is a problem half solved.

Always remember, free advice is worth exactly what you pay for it!

http://www.ap-dynamics.ab.ca/

 

[TheTick]

Pipe is NEVER for structure.

 

[bigzeke]

I recently bought the wrong size tube fitting because I didn't understand the sizing in CPS (Copper Pipe Size). Apparently some tubing products are being sized according to the IPS nomenclature, using the ID as the size.

 

[waross]

I have used schedule 10 PVC and I have used EMT. Not the same. The old CEC dictated that the outside dimension of EMT be such as to make threading with standard dies impracticable and it is sized acordingly. Schedule 10 is the same size OD as schedule 40. And I have encountered PVC tubing made to Electrical Metalic Tubing sizes.
And to stir the pot, we were taught that pipes conveyed fluids and tubes coonveyed electrons.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[SnTMan]

Well, to back up a bit...

A pipe gives a wise man time to think...

And a tube is what they feed you thru.

 

[rmw]

And a pipe is what you dream about the good ole days through.

rmw