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how to recognize pipe & tube?
2

how to recognize pipe & tube?

how to recognize pipe & tube?

(OP)
Dear all
we have auxiliary piping for the pump seal plan
i don't have any related document,
how i can recognize that is pipe or tube?
the picture for two pump were attached.

RE: how to recognize pipe & tube?

It appears to be tubing because there is a compression fitting on one end.

RE: how to recognize pipe & tube?

2
The definition is pretty simple. Tubing is manufactured to a specified OD, Piping is manufactured to a specified "nominal pipe size" (NPS) which up to 12 inch does not match either ID or OD. 14-inch and larger NPS is OD, so you have to look at the NPS definitions from ANSI (e.g., if a 30-inch pipe has a wall thickness that matches a published ANSI grade then it is pipe, otherwise it is tubing), not that it really matters, if you ordered 30 inch tubing your supply house would be happy to send you pipe for a tubing price (tubing tends to be manufactured to closer tolerances than pipe and that increased precision has a price).

David Simpson, PE
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist

RE: how to recognize pipe & tube?

The short piece coming out of the seal is threaded pipe, then it all looks like tubing other than that. A little unusual to see tubing welded to a flange, but that's what it looks like. Some of those 90* bends do not look possible for hard pipe.

RE: how to recognize pipe & tube?

To answer the OP's questions;
- either by marking on the hollow cylindrical part (tube is typically manufactured to ASTM A269 for US tubing, or EN 10216-5 for European stuff).
- or by it's appearance. Tubing tends to be somewhat cleaner and shinier, if you know what I mean. Though (small bore SS316) piping can be shiny too, (SS316) tubing usually has a very bright appearance.

RE: how to recognize pipe & tube?

I think what Dave means is that a nominal 1" tube has an actual OD of 1", wheres a 1" pipe as an actual OD of 1 5/16", 2" pipe is actually 2 3/8" OD.

However other than getting the end fitting right, why do you ask?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: how to recognize pipe & tube?

(OP)
thank you all for your replies.
guidance of zdas04 is great for realizing.but unfortunately the pump is in site.the pictures were taken already.
i asked one friend who has been in purchasing the pumps,he told me they were pipe and 1/2" ,sch 80
but can pipe bent like this?
as entrance to the mechanical seal is threaded.my question is that can it possible for each pipe?or there is limitation base on the pipe size?
my questions are just for knowing more about pipe and tube.

RE: how to recognize pipe & tube?

Yes pipe can be bent like that. 1/2" Sched 80 pipe is 0.840 inch OD and 0.546 inch ID. 1/2 inch tubing is 0.5 inch OD. As you should be able to see, a pipe fitting will not properly connect with tubing and vice versa. The 1/2 inch ASME B16.5 Class 150 flange on the pipe is a dead give away. As is the compression fitting on the tubing.

David Simpson, PE
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist

RE: how to recognize pipe & tube?

It seems you probably have a pipe there. Its coming into the bore of a Slip-On flange. Standard flanges (ASME B16.5) are made acc. to nominal pipe sizes.
You may simply measure the outside diameter (do it on a straight section). The OD for NPS 1/2" is 0.84" (21.336 mm) regardless to the sch.
There are rules for pipe bending. You may see at ASME B31.3 ; 304.2

RE: how to recognize pipe & tube?

The image is not clear so it is hard to determine.

Either piping or tubing may be used. Tubing is more common because it is more flexible.

In this example, it appears to be tubing because you would not be able to screw the piping into the threads because of the overall shape of the piece. It would be easier to install if compression fittings were used.

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