Carbon steel ERW pipe, CS ERW pipe

What is Carbon Steel ERW Pipe?

Carbon steel ERW pipe (CS ERW Pipe) refers to a steel pipe welded by carbon steel through resistance welding.

Hunan Standard Steel Co., Ltd (HSCO) is a well-known manufacturer and exporter of Carbon Steel ERW Pipes, and its products are famous for their precision design, light weight, corrosion resistance, reasonable structure, stable quality, economy, etc. We have set an example in terms of quality and performance by manufacturing and supplying CS ERW Pipes domestically and internationally, which are mainly used in heavy manufacturing industry, construction industry and low and medium pressure piping applications due to their high strength and pressure bearing capabilities. Our clients can avail a wide range of Carbon Steel Electric Resistance Welded Pipes from us that are manufactured as per prevailing industry standards.

What is Carbon Steel Pipe?

The term Carbon Steel Pipe can be used to describe various metal tubular items whose main alloying element is 0.12%-2% carbon. In addition to the carbon elements chromium, cobalt, molybdenum, nickel, niobium, titanium, tungsten, vanadium and zirconium may be added to obtain their respective alloying effects. For example, A333 Grade 6 pipe has high tensile strength and impact properties in cryogenic applications and is used at room temperature or higher compared to A106 Grade B pipe which has low tensile strength. This is achieved by adding manganese above 0.9%, which is limited to 0.65% in A106 pipe.

In general, pipes are called carbon steel pipes when the maximum specified content of manganese is 1.65%, silicon content is 0.6%, and copper content 0.6% does not exceed the specified limits.

Carbon steel pipes are further divided into four categories:
Low Carbon Steel Pipe - Carbon Content: 0.55-1.05%
Medium Carbon Steel Pipe - Carbon Content: 0.25-10.6%
High Carbon Steel Pipe - Carbon Content: 0.9-2.5%
Ultra High Carbon Steel Pipe - Carbon Content: 2.5-3.0%

High carbon steel pipes can become harder and harder with lower ductility through quenching and tempering as the carbon content increases. High carbon steel pipes may have low welding ability and low melting point if not heat treated. Large diameter pipes used for water transportation are generally made of carbon steel.

Based on the manufacturing method, carbon steel pipes can be divided into 3 different types:

1. Seamless pipe - a pipe formed by passing hot steel through a die to form the pipe. Carbon steel seamless pipes are manufactured in the range of in a range of 1/2"-36". Although this is the most expensive method due to the machinery and time involved in manufacturing, it is the most reliable method ever invented.

2. Welded pipes - formed by wrapping the steel plate in a circular motion and then welding at the seams are called welded pipes. These pipes are in high demand due to their cheap price. Depending on the type required, these pipes are welded in the following forms

a. ERW: Electric Resistance Welded Pipes
b. EFW: Electric Fusion Welded Pipes
c. HFW: High Frequency Welded Pipes
c. SAW: Submerged Arc Welded Pipes (LSAW/SSAW/DSAW)

3. Casting Mold Pipes - The old and oldest method of casting hot liquid. These pipes are rarely heat treated.

What is ERW Steel Pipe?

ERW pipe refers to straight seam electric resistance welded pipe (Electric Resistance Welding, abbreviated as ERW). Electric resistance welded pipe is produced by low-frequency or high-frequency resistance. It occupies an important position in the field of oil and natural gas transportation. This pipe is designed for medium and low pressure transportation needs. Its manufacturing process is unique. The weld is formed by melting the steel strip body. Compared with ordinary welded steel pipes, it has better mechanical strength. The most common standard for ERW pipe is ASTM A53. Typically ranges from 1/2 inch to 24 inches and larger, depending on the application.

Electric resistance welded steel pipes are divided into two forms: AC welded steel pipes and DC welded steel pipes.
AC welding is divided into low-frequency welding, medium-frequency welding, ultra-medium-frequency welding and high-frequency welding according to frequency. High-frequency welding is mainly used for the production of thin-walled steel pipes or ordinary wall steel pipes. High-frequency welding is divided into contact welding and induction welding. DC welding is generally used for small diameter steel pipes.

ERW straight seam welded pipes are characterized by high strength and durability, and are suitable for fluid transportation and other structural applications. Carbon steel ERW pipes are steel pipes with advanced product performance, leading quality and relatively economical performance in the field of oil and gas storage and transportation.

Manufacturing process of Carbon Steel ERW Pipe:

1. Raw material preparation: Select suitable steel strip coils and check the quality, size and chemical composition of the steel strip.
2. Uncoiling of steel strip: Unroll the rolled steel strip.
3. Leveling of steel strip: Straighten and level the steel strip through a leveling machine to eliminate the bending and wavy shape of the steel strip.
4. End trimming: Trim the two ends of the steel strip to ensure alignment during welding.
5. Forming of steel strip: Bend the steel strip into a tubular shape through a forming machine.
6. High-frequency resistance welding: Use the resistance heat generated by high-frequency current passing through the contact point to instantly heat the edge of the steel strip to the welding temperature and pressurize to achieve welding.
7. Remove internal and external burrs from the weld: Remove the burrs on the inner and outer surfaces of the weld through a special device to ensure the quality of the weld and the smoothness of the inner wall of the steel pipe.
8. Heat treatment of weld: Perform appropriate heat treatment on the weld to improve the organization and performance of the weld.
9. Sizing and shaping: The diameter and shape of the steel pipe are precisely adjusted and shaped by the sizing machine.
10. Nondestructive testing: The quality of the steel pipe weld and pipe body is checked by nondestructive testing methods such as ultrasonic and eddy current.
11. Cutting and finished product inspection: The steel pipe is cut to the specified length and subjected to final quality inspection, including inspection of appearance, size, performance, etc.

Application of Carbon Steel ERW Pipe:

Carbon Steel ERW Pipe is widely used in various industrial applications, including:

(1) Oil and Gas Industry
Due to its high pressure bearing capacity and durability, it can be used for the transportation of oil, natural gas and petroleum products.

(2) Construction Industry
Structural applications such as building frames, scaffolding and support columns.

(3) Water Transportation
Due to its corrosion resistance, it is used in the distribution and transmission systems of water and other fluids.

(4) Industrial Process
Transport various fluids and gases in industrial processing plants.

Read more: ERW Pipe Grade and Specification or SAW vs ERW and EFW Welded Steel Pipe