piping Vs tubing
piping Vs tubing
(OP)
Which is the difference between piping and tubing ?
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RE: piping Vs tubing
For tubing see ASTM A 1016, 213, 268, 269, 519, 632, 789; ASTM B 163, 165, 423, 521, 704 or F 1387;
Fewer ASME standards apply. Exmaples include ASME Sec II SA-213 and ASME SB-423.
Really high pressure low density polyethylene flows in really thick tubing.
Pipe
For pipe see ASTM A 105, 106, 182, 312, 333, 53; ASTM F 1155, 1387, etc. More ASME standards exist such as B31.1, B31.2, B31.3, B31.4, B31.8, B36.10M, B36.19M, etc. The last two are significant.
RE: piping Vs tubing
"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."
RE: piping Vs tubing
1) Pipe is typically manufactured to specific thicknesses (schedules). Tubing often is also, but the tubing thicknesses do not coincide wth those of piping.
2) Pipe is normally thicker than tubing. In fact, I am not aware of any pipe being thinner than tubing of the same nominal size, but this may be my ignorance rather than because it is actually the case.
3) I view piping as something that "is used as is". Piping is rarely bent while tubing often is.
4) Joining methods differ. Piping is typically welded, flanged, or screwed. Tubing is often connected with solder or compression fittings.
These are not hard & fast rules. Rather numerous exceptions can be found.
RE: piping Vs tubing
RE: piping Vs tubing
Maybe a smallish D/t ratio suggests tubular ?
Her's a further confusing point ..Why is there no such word as 'pipular ?
RE: piping Vs tubing
Pressure Rating 50000
psi (kPa) (345000)
Nominal Size ID in. (mm) OD in. (mm)
0.75 (20) : 2 (50)
0.875 (22): 2 (50)
1 (25) : 2.625 (70)
1.125 (28) : 2.625 (70)
1.25 (30) : 3.25 (80)
1.375 (35): 3.312 (80)
1.5 (40) : 3.937 (100)
1.75 (45): 4.125 (100)
2 (50) : 4.687 (119)
2.25 (55) : 5.5 (140)
2.5 (63.5) : 5.75 (146)
2.75 (70) : 6.437 (160)
3 (75) : 7.000 (180)
3.5 (90) : 8.187 (200)
4 (100) : 9.375 (250)
RE: piping Vs tubing
Tube is structural. It may be round, but may just as easily be rectangular. Tube is always measured by the outside dimensions.
I theory a two inch round tube should just slip inside a two inch pipe.
RE: piping Vs tubing
Tubing IS used for carrying fluids, amongst numerous other purposes.
Rigid metal tubing is sized by OD and wall thickness, in North America these being even fractions of an inch: common sizes are 1/8, 1/4, 3/8, 1/2, 5/8, 3/4, 1, 1.5, 2, 3 and 4", though oddballs such as 1.25" OD can also be found. Pipe is sized by OD and "schedule" per an archaic standard, which switches back to ODs at 14". Tubing is used for instrumentation and small process lines, high pressure hydraulic and pneumatic services etc. as well as in heat exchangers. In these services it is often joined by compression fittings, orbital welding, and by cone/thread fittings at high pressures.
At sizes to 6", rigid stainless steel tubing is also used extensively in food/beverage and bioprocess applications where sanitary/cleaning considerations predominate over pressure/temperature handling capability. In these services it is often joined by orbital welding and TriClamp-type fittings.
RE: piping Vs tubing
For example, exhaust tubing used in Automotive exhaust systems.
Soft drawn copper tubing used in household plumbing.
Boiler tubes carry either fire or water.
But you will find all these "tubes" are still measured and sized by their outside diameter.
The definition still stands:
tubes = OD as nominal size reference
pipe = ID as nominal size reference
RE: piping Vs tubing
I always thought pipe was designated by its nominal diameter, not internal.
RE: piping Vs tubing
How do you define "nominal" pipe size if not by bore?
RE: piping Vs tubing
To answer warpspeed - pipe (US std.)is measured by OD and carries a nominal size - the ID varies due to wall thickness depending on the pressure rating of the particular pipe.
for example all 6" steel pipe have the same OD - 6" pipe sch.40 has ID 6.065", sch 80 ID 5.761" and sch 160 ID 5.187"
You will find similar in BS standard pipe sizing as well.
RE: piping Vs tubing
RE: piping Vs tubing
http://en.wikipedia.org/wiki/Fire-tube_boiler
RE: piping Vs tubing
Heat transfer via fluids, like, not fire in the tubes.
RE: piping Vs tubing
I am extremely surprised that any engineer has never heard of a fire tube boiler.
The original poster asked a genuine question which I attempted to answer. Some people here are being petty and provocative, which is not at all helpful.
RE: piping Vs tubing
Fire tube boilers indeed contain the flame inside the tube. Not all engineers work with boilers. Some of us work with larger boilers where the heat radiation is on the outside of the tubes. Most of us rarely work with 4-inch OD tubing containing 50,000 psi.
Based upon ASME B36.10, a 2-inch OD tube may fit inside NPS 2 pipe at schedule 40 and below; and will not fit inside the pipe at schedule 80 and above. Various standard specifications define the requirements for several types of tubing and several types of piping.
Next thread please.
RE: piping Vs tubing
RE: piping Vs tubing
Tubes are normally enclosed in the walls of a heat exchanger or boiler and their failure is a bit less likely to hurt a worker if they failed.
The statement above applies to heat exchangers, boilers, furnaces etc. but not my transmitter impulse tubing, analyzer sample tubing or the high-pressure process tubing described in some previous posts.
RE: piping Vs tubing
http://www.mckenziecorp.com/boiler_tip_8.htm
The name firetube is very descriptive. The fire, or hot flue gases from the burner, is channeled through tubes that are surrounded by the fluid to be heated. The body of the boiler is the pressure vessel and contains the fluid. In most cases this fluid is water that will be circulated for heating purposes or converted to steam for process use.
Every set of tubes that the flue gas travels through, before it makes a turn, is considered a "pass". So a three-pass boiler will have three sets of tubes with the stack outlet located on the rear of the boiler. A 4-pass will have four sets and the stack outlet at the front.