Table of content
Introduction
Steel pipes come in different types, such as ERW steel pipes, seamless pipes, carbon steel pipes and stainless steel pipes. This article will mainly introduce ERW steel pipes. What is the name of ERW steel pipes? ERW stands for electric resistance welding. The following is a detailed introduction to how this steel pipe is made, its functions and its advantages and disadvantages.
What is ERW Steel Pipe?
ERW steel pipes are made from steel plates or steel coils. First, they are rolled into a cylindrical shape and welded longitudinally using high-frequency current to form a steel pipe. This process does not require additional welding materials, and the welds are strong and clean.
How is ERW Pipe Manufactured?
The main production processes of ERW pipes are as follows:
- Uncoiling: Unroll the steel coil through an uncoiling machine.
- Forming: Mechanically shape the steel coil into the shape of a steel pipe.
- Sizing: Adjust the pipe to the required diameter.
- Welding: Use high-frequency resistance welding to weld the edges that need to be welded to form a steel pipe.
- Cutting: Cut the steel pipe into a specified length.
- Test: Measure the strength and welding of steel pipes.
What is ERW Pipe Used For?
ERW pipes are highly strong and affordable, so they are widely used.
The main uses are as follows:
Oil and natural gas transportation pipelines
Scaffolding structure support
Automobile exhaust pipes
Fences and frames
Some machinery
ERW Pipe Specifications and Sizes
ERW has different diameters, wall thicknesses and lengths according to different standards. Some common standards are:
ASTM A53: General pipes
ASTM A252: Piling pipes
APL 5L: Oil and gas pipelines
IS1239, IS3589: Indian standard pipes
The common specification table is as follows:
| Parameter | Common Range |
| Outer Diameter | 1/2 inch to 24 inches |
| Wall Thickness | 1.2 mm to 15 mm |
| Length | 6m or custom |
| Steel Grades | ASTM A53, API 5L, EN10219 |
| Surface Finish | Black, galvanized, oiled |
ERW vs Seamless Pipe: What’s the Difference?
For the comparison between the two, in addition to the different manufacturing processes and different uses, there are also some different mechanical properties.
Here are some differences:
| Feature | ERW Pipe | Seamless Pipe |
| Manufacturing | Welded from steel coils | Made by piercing solid billet |
| Weld Seam | Yes (longitudinal) | None |
| Pressure Capacity | Lower than seamless | Higher — ideal for critical use |
| Size Range | Up to 24 inches | Smaller and larger sizes available |
| Cost | More affordable | More expensive |
Which Is Better?
ERW pipes are generally used in low pressure or structural applications.
Seamless pipes are more used in high pressure, high temperature pipeline systems.
Which is Better: Seamless or ERW Pipe?
Depending on the specific use, different steel pipes have different advantages.
The following are the situations where ERW pipes are used:
In piping systems with moderate pressure and temperature
In structural supports such as scaffolding and fences
Under limited budget
The following are the situations where seamless pipes are used:
In piping systems with high pressure and high temperature
In some chemical pipes
For some pipes with strict requirements
What are the Disadvantages of ERW Pipes?
The disadvantages of ERW pipes are:
It is not suitable for piping systems with high temperature and high pressure, because the welds may leak in high pressure systems.
For piping systems with particularly strict dimensional requirements, there may be differences due to different production processes.
In corrosive environments, an anti-corrosion layer is required because the welds are easily corroded.
What is the Difference Between ERW and MS Pipes?
ERW is a steel pipe made by resistance welding.
MS refers to the material, i.e. low carbon steel.
Both can be combined to represent a steel pipe.
Example:
MS ERW pipe: low carbon steel ERW welded steel pipe.
ERW Pipe Price: How Much Does It Cost?
Price is mainly determined by: material, diameter, wall thickness and surface coating treatment.
Average Market Price:
US$500-900 per ton, the price will increase by 10%-15% after galvanizing. (For reference only, the specific price should be determined according to market conditions.)
Advantages of ERW Steel Pipes
The main advantages of ERW steel pipes are:
It is easier to make different diameters and lengths during production.
It is suitable for large projects in non-high-pressure environments because of its affordable price.
Welding is smooth, high precision and easy to coat.
Summary
ERW steel pipe is one of the universal steel pipes in the world and is widely used. Each of them has its own advantages and disadvantages. Whether to choose to use ERW steel pipe needs to be selected according to actual conditions.
Some of the main features of ERW are:
Suitable for use in medium and low pressure pipeline systems.
It is mostly used in some building scaffolding.
The price is relatively affordable.
The production process is mainly welded from steel coils.
I hope this article helps you understand ERW steel pipes
