PIPE --- Standard Pipe
TUBE --- non-standard tube
Tubes manufactured to ANSI and API standard specifications are called PIPE, and their dimensions are expressed as “nominal diameter.” All other tubes not manufactured to standard tube specifications are called TUBE or TUBING, and their dimensions are expressed in terms of outside diameter.
Tube is a positive deviation tube with heat exchange.
Pipe is a positive or negative deviation tube without heat exchange.
Note: ANSI – American National Standards Institute (ANSI – American National Standards Institute)
1. the difference between sizes
Tube and Pipe have standards; the standard series of tubes is more than Pipe. The pipe DN standard is not the outer diameter but is slightly smaller than the outer diameter and larger than the inner diameter. Can also do non-standard
2. the difference between the usage
The tube is generally used in the container, especially the heat exchanger tube, and Pipe refers to more equipment outside the Pipe, so the general tube is translated as “pipe,” and Pipe is translated as “pipe.”
The difference between Tube, Pipe, Tubing, and piping.
The ASME Boiler and Pressure Vessel Code is very strict about the meaning of the terms tube, Pipe, Tubing, and piping, which are used in different applications. I have summarized my understanding of the four terms below for your discussion.
1. The tube is round or has a continuous perimeter of any other cross-sectional shape of the hollow product. The dimensions of a round tube can be specified in terms of any two of the three diameters: outside diameter, inside diameter, and wall thickness.
2, The Pipe by ASNI B36.10 and B36.19 (for stainless steel) is listed in the nominal size of the round cross-section of the tube, and its diameter is expressed in NPS No. NPS No. The actual outside diameter is inconsistent with the actual outside diameter, such as NPS8, whose outside diameter is 8.625 inches. The wall thickness of the Pipe is indicated by schedule No. The same NPS No. Can have various Sch. No. The Sch. No. is divided into standard wall thickness (STD), extra thick wall thickness (XS), extra thick wall thickness (XXS), etc. The Sch. No. is used to indicate the wall thickness of the Pipe.
The primary difference between a tube and a pipe is the size standard on which they are manufactured. Secondly, a Pipe is only a round tube, whereas a tube can have various cross-sectional shapes. Pipe is just a special case of a tube. Both tube and Pipe refer to the raw material produced by the material manufacturer.
3. Tubing is a product made from the tube by selecting the diameter and thickness after calculation according to the formula of PG-27.2.1[ OD D≤5in.(127mm)] and processing according to the design requirements (e.g., bending, beveling, and even painting, etc.). We can call it tube fittings.
4. Piping General selection of Pipe Selected NPS and Sch. No, after calculation according to the formula of PG-27.2.2, and according to the design requirements of the products made after processing, we call the Pipe. Still, the boiler manufacturer generally calls these tubes conduit.
The difference between tube, pipe, and tubing, piping. The former is the raw material of a manufacturing plant, while the latter is the product made by a boiler manufacturer or pressure vessel manufacturer. This is where the Boiler and Pressure Vessel Code rules distinguish between the meaning and usage of these four terms. Of course, a pipe that transports fluid and is installed in place is also called piping. Therefore, we should distinguish between the translation of these four terms to avoid confusion and misunderstanding.
From the ASME standard understanding, the difference between tube and Pipe is not difficult to distinguish; the so-called difference is just the implementation of the standard is different. Tube and Pipe are just the implementation of the standard are not the same; nothing else is the same, such as the same TP304 material pipe, the implementation of the SB338 standard is a tube, and the implementation of the SB861 is a pipe. ASME standard is already written under the name of the tube or Pipe. Tube standard requires the tube wall thickness of the minimum wall thickness; wall thickness can not be negative deviation; pipe standard requirements for the minimum wall thickness, wall thickness can not be negative deviation, the pipe standard requirements for the minimum wall thickness, wall thickness can not be negative deviation, the pipe standard. ASME standard is written under the name of the tube or Pipe. Tube standard requirements for the minimum wall thickness, wall thickness can not have a negative deviation, pipe standard requirements for the average wall thickness of the tube wall thickness, wall thickness can be positive or negative deviation, in addition to the two types of pipe implementation standard requirements of the test method is not the same, such as tube requirements flaring flanging test, pipe standard on the standard does not have this requirement So if the heat exchanger tubes need to expand the tube should be used tube.
I recently came across an old book and found that there is a difference between Pipe and tube in ASME, so here it is for you:
PIPE generally refers to the inner diameter and wall thickness number (SCH), including welded and seamless tube, the primary function of the pipeline for the delivery of fluids, and Tube outside the diameter and wall thickness of the tube, including welded and seamless tubes, the primary function of heat transfer, such as heat exchanger tubes, condenser tubes, the weld process evaluation, the branch focusing on the In the welding process evaluation, the branch focuses on the function of the tube is not differentiated, so Pipe and tube can be shared.
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