Pipes are used for transporting fluids and gases in Chemical, Petrochemical, Power Plants, Refineries, Storage units, Compressed air systems, Plumbing systems, etc. They are circular in cross-section and specified by Nominal Pipe Size.
What is a Tube?
Tubes are used for mechanical applications (Heat Exchanger, Fired heater, Boiler, etc.), for instrumentation systems (used for measuring instruments); for structural applications, etc and could be rigid or flexible. They are specified by their outer diameter and tube wall thickness, in inches or in millimeters.
Differences between Pipe and Tube
From a layman’s viewpoint, Both Pipe and Tube seem to be the same as they have many similarities like both are hollow, usually made from metals, can transfer fluids, etc. Many a time, these terms are used interchangeably. But in actual practice Tubes and Pipes are not the same as both possess different features. Through this article, we will try to investigate all such characteristics based on a few parameters like Size, Shape, Diameter, Thickness, Use, Availability, End Connection, Design Standard, etc.
Sr No
Parameter
Pipe Characteristics
Tube Characteristics
1
Shape
Pipes are always cylindrical or round in shape
Tubes are usually cylindrical in shape. However, tubes of different other shapes like square, rectangular, etc. are available.
2
Size
A pipe is Specified by Nominal Pipe Size (NPS) or Nominal Bore (NB).
The size of the Tubes is specified in millimeters or in inches by outside diameter.
3
Diameter
The outside diameter of pipe up to size 12” is numerically larger than the corresponding pipe size
The outside diameter of tubes is numerically equal to the corresponding size.
4
Thickness
Pipe Wall thickness is expressed in schedule numbers that can be converted into mm or inches.
Tube Wall thickness is expressed in millimeters, inches, or BWG (Birmingham wire gauge.)
5
Thickness Increment
Pipe thickness depends on the schedule, so there is no fixed increment
The thickness of tubes increases in standard increments such as 1 mm or 2 mm
Pipe vs Tube
Difference Between Pipe and Tube
Sr No
Parameter
Pipe Characteristics
Tube Characteristics
6
Application
Pipes are extensively used in all Process, Power & Utility lines to carry fluids.
Tubes are used in tracing lines, tubes for heat exchangers & fired heaters & instrument connections. They are more prevalent in the medical area, construction, structural, or load bearing.
7
Availability
Pipes are available as the small bore and the big bore
Normally small-bore tube is used in process piping. For structural use, tubes are available in custom sizes.
8
Structural Rigidity
Pipes are always rigid and resistant to bending
Tubes are available as rigid as well as flexible depending on the application. Rigid tubes are normally used in structural applications whereas copper and brass tubes can be flexible.
9
Joining and Stability
Joining pipes is more labor intensive as it requires flanges, welding, threading, etc.
Tubes can be joined quickly and easily with flaring, brazing, or couplings, but for this reason, they don’t offer the same stability
10
Tolerance
Pipe tolerances are not too restrictive.
Tolerances are very strict with tubes compared to pipes and tubes are often more expensive to produce than pipes
Pipes used in operating process plant
Sr No
Parameter
Pipe Characteristics
Tube Characteristics
11
Manufacturing
Pipe manufacturing is easier as compared to tubes
Tubes need more cumbersome tests, inspection, and quality control than pipes.
12
Cost
Cheaper
Costlier
13
Packing & Delivery
Delivered in the bundle as a bulk item. Delivery time is short.
Tubes are usually wrapped with a wooden box or thin film and delivered with much care. Delivery time is longer.
14
Production Quantity
Pipes are produced in mass quantity and for long-distance applications.
Tubes are produced in small quantities depending on requirements.
Tubes used inside a Fired Heater
Sr No
Parameters
Pipe Characteristics
Tube Characteristics
15
End Connection
The end connection of pipes is normally plain or beveled for welding purposes
Tubes are available with coupling ends, irregular ends, special screw thread, etc.
16
Surface Finish
The inner and Outer surface of the pipe is rough in comparison to the tube
Tubes are manufactured on both the inner and outer surfaces as smooth
I am a Mechanical Engineer turned into a Piping Engineer. Currently, I work in a reputed MNC as a Senior Piping Stress Engineer. I am very much passionate about blogging and always tried to do unique things. This website is my first venture into the world of blogging with the aim of connecting with other piping engineers around the world.
6 thoughts on “Comparison of Pipe and Tube | Pipe Vs Tube”
Hi, very useful & detail difference has given between tube & pipe. It’s really helpful, which added few new point in knowledge.
Thanks
Dear Anup thanks, I am Noor ul Arefeen from Pakistan. Your above subject is very informative and you have tried to contain very big topic in short spain. I am running my own business in mechanical fabricaion. I will keep in touch with for further knowledge. Thanks once again.
HI ANUP SIR,
IAM ALSO A MECHANICAL ENGINEER GRADUATE AND WORKING AS PROCESS DESIGNER. AND I HAVE ALSO INTEREST TO BECOME A PIPING ENGINEER, CAN YOU PLEASE SUGGEST HOW I BECOME THE PIPING ENGINEER.
AND YOURS ARTICLES ALSO VERY USEFUL TO GAIN THE KNOWLEDGE ABOUT THIS FIELD THANK YOU VERY MUCH
Instrumentation engineering plays a crucial role in the oil and gas industry, ensuring the safe, efficient, and reliable operation of facilities across exploration, production, refining, and...
ASME B31.3, the "process piping" code, provides guidelines for the pressure leak testing of piping systems. The primary goal of these tests is to ensure the integrity and safety of the piping system...
Hi, very useful & detail difference has given between tube & pipe. It’s really helpful, which added few new point in knowledge.
Thanks
Dear Anup thanks, I am Noor ul Arefeen from Pakistan. Your above subject is very informative and you have tried to contain very big topic in short spain. I am running my own business in mechanical fabricaion. I will keep in touch with for further knowledge. Thanks once again.
I’m also a MECHANICAL ENGINEER From
INDIA…
HI ANUP SIR,
IAM ALSO A MECHANICAL ENGINEER GRADUATE AND WORKING AS PROCESS DESIGNER. AND I HAVE ALSO INTEREST TO BECOME A PIPING ENGINEER, CAN YOU PLEASE SUGGEST HOW I BECOME THE PIPING ENGINEER.
AND YOURS ARTICLES ALSO VERY USEFUL TO GAIN THE KNOWLEDGE ABOUT THIS FIELD THANK YOU VERY MUCH
Sir so many piping draftsmans are hired on temporary or contract basis. What is their future ?
Pipe has a circular cross-sectional view whereas a tube can be circular, triangular, rectangular, square, oval etc