What are the materials of steel pipes?

What is steel pipe?

Steel pipe refers to steel with a hollow section whose length is much larger than its diameter or circumference.

1. According to the cross-sectional shape, it is divided into round, square, rectangular and special-shaped steel pipes;
2. According to materials, they are divided into carbon structural steel pipes, low alloy structural steel pipes, alloy steel pipes and composite steel pipes;

3. According to the purpose, it is divided into steel pipes for transportation pipelines, engineering structures, thermal equipment, petrochemical industry, machinery manufacturing, geological drilling, high-pressure equipment, etc.;

4. According to the production process, it is divided into seamless steel pipe and welded steel pipe. Seamless steel pipe is divided into hot-rolled and cold-rolled (drawn). Welded steel pipe is divided into straight seam welded steel pipe (ERW/LSAW) and spiral seam welded steel pipe (SSAW). 

Steel pipes are not only used to transport fluids and powdery solids, exchange heat energy, and manufacture mechanical parts and containers, but they are also a kind of economical steel. Using steel pipes to manufacture building structural grids, pillars and mechanical supports can reduce weight, save 20 to 40% of metal, and enable factory-like mechanized construction. Using steel pipes to manufacture road bridges can not only save steel and simplify construction, but also greatly reduce the area of protective coating, saving investment and maintenance costs.

Characteristics of steel pipes:
1. High strength: Steel pipes have high strength and pressure resistance, and are suitable for workplaces with heavy pressure and large loads;
2. Strong corrosion resistance: Steel pipes can maintain a certain degree of corrosion resistance in different working environments, especially stainless steel pipes, which have good corrosion resistance;
3. Good toughness: Steel pipes are not easily damaged during transportation and installation and have good toughness;
4. Good formability: Steel pipes can be processed into various shapes and specifications in a variety of ways and have good formability.

Material classification of steel pipes:

Steel pipe is a tubular material, usually made of carbon steel, alloy steel, stainless steel and other materials. Among them, carbon steel pipes are mainly composed of carbon and other elements with a carbon content of less than 0.8%. They have higher strength but poor corrosion resistance. Alloy steel pipes are composed of a variety of alloy elements other than carbon and iron, such as chromium, molybdenum, manganese, etc., and have high strength and corrosion resistance. Stainless steel pipes are made of steel containing chromium and have good corrosion resistance, strength and toughness. details as follows:

1. Carbon steel pipes
Carbon steel pipes (cs pipe) refer to steel pipes with carbon as the main alloy element. Carbon steel pipes are cheap, have high hardness, good toughness and good weldability, and are one of the most commonly used metal pipe materials. Carbon steel pipes can be divided into low carbon steel pipes, medium carbon steel pipes and high carbon steel pipes, which are suitable for transporting low-pressure fluids, water, gases, steam and other liquids with low energy consumption.

2. Stainless steel pipes
Stainless steel pipes (ss pipe) are usually steel pipes with chromium and nickel as the main alloy elements. They have good corrosion resistance, high temperature strength and hot and cold processing properties. Stainless steel pipes have a variety of grades and uses, such as SUS304, SUS316, SUS321, etc. Among them, 304 has good processing and welding properties, while 316L has higher corrosion resistance and is widely used in pharmaceuticals, food processing, chemical industry, marine engineering, etc. field.

3. Alloy steel pipes
Alloy steel pipes are steel pipes made of a mixture of various metal elements. Adding nickel, chromium, molybdenum and other elements can increase the strength and corrosion resistance of the steel pipe. Alloy steel pipes have corrosion resistance, high hardness, high temperature resistance and good wear resistance. Common alloy steel pipes include Cr-Mo alloy steel pipes, Mn-V alloy steel pipes, etc., which are widely used in the transportation of high-temperature, high-pressure, and corrosive media such as chemicals, petroleum, natural gas, and nuclear power.

Other steel pipe materials:
In addition to the common steel pipe materials mentioned above, there are also other steel pipe materials, such as copper pipes, galvanized steel pipes, aluminum-plastic composite pipes, etc. Copper pipes and galvanized steel pipes have the advantages of light weight, low price, and high reliability, and are suitable for use in households, industries, underground gas pipelines, and other fields. Aluminum-plastic composite pipes have the characteristics of high strength, corrosion resistance and good plasticity, and are suitable for water supply, chemical transportation and other fields.

Conclusion:

Steel pipe is an indispensable material in the industrial and construction fields. Choosing the right material is crucial to ensuring the quality of the project. Steel pipes are mainly made of carbon steel, stainless steel, alloy steel and other steel pipe materials. Choosing the appropriate pipe material can meet the requirements for pipeline strength, corrosion resistance, temperature, pressure and other performance requirements in different occasions.

Go here to learn more: Carbon steel vs Stainless Steel