Standards of black carbon steel pipe

Black carbon steel pipe is a type of carbon steel pipe that has not undergone any coating treatment. Its surface is covered with a natural black layer of iron oxide, hence the name black carbon steel pipe. Black carbon steel pipes are generally made of low-carbon steel (with a carbon content of 0.17% to 0.30%), featuring excellent processing performance. They are widely used in fluid transportation, structural support, mechanical manufacturing and other fields, and have good toughness and weldability.

The relevant standards for black carbon steel pipes are very extensive, covering various countries and regions. Below, I list some common standards for black carbon steel pipes for everyone:

American Standard (ASTM/API

ASTM A53: Carbon structural steel tubes for pressure transmission, covering welded tubes and seamless tubes. It is mainly divided into two grades, A and B. Among them, Grade B has higher requirements for chemical composition and mechanical properties and is more widely used. It is mainly used in structural application fields and for the transportation pipelines of water, gas and oil at low pressure.
ASTM A106: Seamless carbon steel pipes for high-temperature services, mainly including grades A, B and C, are suitable for high-temperature environments and can withstand medium temperatures above 450℃ at most. It is widely applied in high-temperature steam pipes, heat exchanger pipes, etc.
API 5L: Pipes for the oil and gas industry can be classified into PSL1 and PSL2 based on the strength of the steel grade. Common ones include X42, X52, X60, etc. It is often used in natural gas pipelines and long-distance oil and gas transportation systems.
ASTM A500: Cold-formed welded or seamless structural tubes (round, square, rectangular), mainly used for structural purposes, not often used for fluid transportation.

European Standard (EN/DIN

EN 10255 (DIN 2440/2441) : General-purpose welded and seamless carbon steel pipes, mainly divided into two grades A and B. Among them, grade B has higher strength and is widely used in construction and scaffolding pipes, as well as low-pressure fluid transportation pipes.
EN 10220 / EN 10216 / EN 10217: EN 10220 defines the correspondence table between nominal wall thickness and actual wall thickness; EN 10216-1/2 for seamless pressure tubes; EN 10217-1/2 for welded pressure steel pipes. These standard steel pipes have very strict requirements for dimensions, and their mechanical properties are mainly classified according to steel grades (such as P235, P265, P355, etc.). It is commonly used in boilers, heat exchangers, pressure vessels and high-pressure pipelines.

Japanese Standard (JIS

JIS G3454 / G3456 / G3444: G3454: Seamless steel pipe for low-pressure fluid conveyance; G3456: Welded steel pipe for low-pressure fluid conveyance; G3444: Cold-drawn welded pipe. It features strict chemical composition control and offers a variety of coating options, allowing customers to apply the corresponding coating according to their application requirements. It is widely applied in municipal water supply pipes and HVAC systems.

Chinese Standard (GB/GB/T

GB/T 8163: Seamless steel pipes for fluid conveyance, with main steel grades including 10, 20, 45, etc. It is suitable for conveying general fluids such as water, oil and gas.
GB/T 3091: Welded steel pipes for low-pressure fluid conveyance, available in three grades: A, B, and C, with strict control over thickness deviation and dimensional accuracy. It is mainly used for water supply, gas and HVAC system pipelines.
GB/T 8162: Seamless steel tubes for structural purposes, mainly used as load-bearing components of structures and for the transportation of non-pressure media. Typical applications include mechanical structures, building supports, mechanical manufacturing, etc.

The characteristics of black carbon steel pipes

The reason why black carbon steel pipes are widely used in the construction industry and agriculture and industry mainly lies in their performance characteristics of high strength, high plasticity and high weldability. During use, the black oxide layer on the black carbon steel pipe can protect the steel pipe from external erosion and has certain corrosion resistance. Compared with galvanized steel pipes, black pipes are more economical and practical, and more environmentally friendly. They can be provided in various forms, such as seamless pipes and welded pipes.