ERW Pipes and Tubes Manufacturers & Suppliers
ERW Pipes and Tubes Manufacturers & Suppliers: In this article, we have covered many topics and headings in detail related to its features, types, uses, advantages, and its manufacturers and suppliers like- “What is ERW steel pipes ”, “ERW pipes and tubes manufacturing process”, “how to identify these pipes”, etc.
What is ERW Pipes and Tubes: ERW Full Form
ERW full form is electric resistance welded. The ERW pipes are made from steel coil and the weld seam runs parallel to the pipe. The coil’s width is taken as the same as the circumference of the pipe to be fixed so diameters are limited to a maximum of 24 inches.
What is ERW Steel Pipe?
ERW steel pipes and tubes are round pipes welded from steel plates with longitudinal welds. During the ERW pipe welding process, heat is generated by current flows through the contact surface of the welding area. The current flow heats the two edges of the steel to the point where one edge can form a bond. As a result, the two edges of the tube blank melt and squeeze together under the action of the combined pressure.
Generally, the ERW pipe’s maximum outside diameter (OD) is 24 inches (609mm), and for larger dimensions pipe will be manufactured in submerged arc welded (SAW).
ERW pipes are mostly used to transport natural gas, oil, and other vapor-liquid objects. This steel pipe can meet different requirements of high and low pressure. So, presently, ERW pipes occupy an important position in the field of transportation pipes in the world.
ERW Pipes Manufacturing Process
ERW pipe is manufactured using a cold HR coils flat steel plate converted into a rounded cylindrical tube shape. After it an electric current between the two edges of the steel plate passes to heat the steel plate to a point of force, forcing these edges to form a weld.
Electric resistance welding for ERW pipes and tube manufacturing can be divided into resistance welding and induction welding. In this process, electric current is used instead of flame to heat the edges of the steel sheet for welding. The rotating copper disk is used as an electrode for raising the temperature to about 2600°F for required effective welding. Electric resistance welding (ERW) usually uses alternating current with a frequency of 100 to 800 kHz, (100.000 to 800.000 cycles per second).
The ERW process is characterized by two effects, the skin effect, or the concentration of high-frequency current on the sheet’s edges surface, and the proximity effect. These effects work when the high frequency is concentrated on two adjacent parallel inner edges in the welding wedge before the welding point.
These effects reduce and minimize the heat released during the electric welding process. As a result, the structure of the basic material changes in a relatively small area around the fusion line i.e. the center of the weld. For finishing the weld a scraping device is used to remove the molten material on the inside and outside of the weld.
Features of ERW Pipes and Tubes
The ERW pipes and tubes manufactured by using high-frequency electric current are known for high-quality features and characteristics like:
- The raw material of only high-quality, continuous casting, fully sedated, controlled rolling, fine-grained low carbon steel is used for the manufacturing of ERW pipes and steel tubes.
- ERW steel pipes and tubes have high strength and so perform better.
- They have high toughness.
- They are made with corrosion resistance.
- They have high deformability.
Sparsteel Manufacturing Industries is one of the leading manufacturers and suppliers of ERW pipes and tubes in the UAE, the Middle East, and other MENA countries. We are also one of the largest exporters of ERW pipes in the Gulf.
Types of ERW Pipes Standards
There are different types of pipes that can be manufactured by using the ERW process such as:
- ERW Carbon steel pipe
- ERW Stainless steel pipe
- ERW API Line pipe, etc.
How to Identify ERW Stainless Steel Pipes?
To identify whether a pipe manufactured and supplied to you is ERW, simply read the following stencil on the side of the pipe, for example:
- If the stencil is ASTM A53, this type of pipe is S which means seamless.
- If the stencil is F, this type of pipe is a furnace but welded.
- If the stencil is E, this type of pipe is Electrical resist welded (ERW).
Thus, you can easily identify through the above method whether a pipe is seamless or ERW.
What are the Applications and Usage of ERW Pipes and Tubes
ERW pipes and steel tubes are usually used for transporting gas and liquid objects like oil and gas. The ERW steel pipes are used because they could meet the low and high-pressure requirements for carrying gas and oil. As a result of the innovation and development in ERW technology for manufacturing better quality ERW pipes and tubes in recent years, more and more ERW steel pipes are used in the oil and gas fields, automobile industry, and other fields.
Use of ERW Steel Pipes and Tubes in the Oil and Chemical Industry
Since some years back, there has been a trend all around the world to replace high-cost seamless steel pipes with high-quality ERW pipes. This is mainly because of continuous innovation and development in the production technology of welded pipes, such as:
- Advances in desulfurization technology due to research and development (RnD) have reduced the sulfur content of steel and improved the welding quality of ERW steel pipes and tubes.
- The use of vacuum degassing technology improves the purity of the tube blank strip, reduces inclusions, and improves the weld’s quality.
- Because of adding special elements like V, Ti, and Nb, the carbon equivalent is lowered in the steel sheet which led to the improvement of toughness and strength of ERW steel pipes and tubes.
- The development and introduction of hot rolling technology have improved the strips’ dimensional accuracy which reduced the dimensional deviation of the ERW pipes and tubes.
- And finally, the improvement in quality inspection methods like hydraulic testing machines, ultrasonic non-destructive testing, and other equipment have ensured the quality of the final product, ERW pipes, and tubes.
Advantages of ERW Pipes and Tubes
The advantages and benefits of ERW steel pipes and tubes compared with seamless steel pipes are following below:
- ERW pipes provide higher dimensional accuracy including in diameter and wall thickness than seamless steel pipes. It is because of the high dimensional accuracy of strip rolling and pipe material control.
- ERW steel pipes and tubes have good mechanical properties in comparison to seamless steel pipes. It is also because ERW pipes have a straight seam electric-welded pipe carbon content of less than 12% lower than the seamless pipes and tubes.
- ERW steel pipe with high concentricity, uniform wall thickness
- After heat treatment, the microstructure is uniform in ERW pipes than in seamless pipes and so can not collapse.
- The flattening test of the straight seam ERW steel pipe is better than the seamless test due to the good extension of the steel.
- The ERW steel pipes’ impact toughness is higher than that of seamless steel pipes.
- Longitudinal resistance welded ERW steel pipes are not welded to different metals because of undergoing rigorous online heat treatment, and so the basic properties of welding and material properties are the same.
- There are no fusion metals used during the manufacturing process of ERW pipes and tubes. As a result, the pipe is extremely strong and durable.
- Some technical performances of ERW steel pipes are better than seamless steel pipes, while its price is much lower than that of seamless steel pipes.
- The weld seam of ERW steel pipes cannot be seen or felt. This is an important difference when looking at the double-submerged arc welding process, which left behind an obvious welded bead that might need to be eliminated.
ERW Pipes and Tubes Manufacturers & Suppliers
SPAR Steel Industries is one of the leading manufacturers and suppliers of ERW Stainless Steel pipes and tubes in the UAE, Saudi Arabia, and other Middle East and MENA countries for a long period. Spar Steel manufactures and exports ERW steel pipes in different dimensions and shapes. Its Stainless Steel manufacturing unit is capable of producing large and customized orders from our clients around the world.