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Differences in chemical composition and performance of stainless steel seamless pipes

Jun 5, 2024

According to different materials, seamless steel pipes can be divided into 304 steel pipes, 316 steel pipes and 106 seamless steel pipe. Different steel pipes have different properties and standards.

304 stainless steel seamless pipe

304 stainless steel seamless pipe is a common stainless steel pipe, which is manufactured by seamless process and has excellent corrosion resistance and good mechanical properties. 304 stainless steel is a kind of austenitic stainless steel, containing 18% chromium and 8% nickel, so it is also called 18/8 stainless steel. The following are some main features and applications of 304 stainless steel seamless pipe:

Features:

1. Corrosion resistance. 304 stainless steel has good corrosion resistance and can resist corrosion from most acids, alkalis and salt solutions.

2. High strength. The seamless process makes the pipe have higher strength and pressure resistance.

3. Good processing performance. 304 stainless steel is easy to process and weld, suitable for various manufacturing processes.

4. High finish. The surface is smooth, easy to clean and maintain, and suitable for environments with high cleanliness requirements.

5. High temperature resistance. It can maintain good mechanical properties and stability under high temperature environment.

Specifications and standards:

304 stainless steel seamless pipe has various specifications and standards, and common standards include ASTM A213, ASTM A312, JIS G3459, etc. Common pipe diameters and wall thicknesses can be customized according to specific application requirements.

304 stainless steel seamless pipe

316 stainless steel seamless pipe

316 stainless steel seamless pipe is a high-performance stainless steel pipe that is widely used in various harsh environments due to its excellent corrosion resistance and mechanical properties. The following is a detailed introduction to 316 stainless steel seamless pipe:

Chemical composition

Chromium (Cr): 16-18%

Nickel (Ni): 10-14%

Molybdenum (Mo): 2-3%

Carbon (C): ≤0.08%

Manganese (Mn): ≤2%

Silicon (Si): ≤1%

Phosphorus (P): ≤0.045%

Sulfur (S): ≤0.03%

The addition of molybdenum significantly improves the corrosion resistance of 316 stainless steel, especially in chloride-containing environments.

Features

1. Excellent corrosion resistance. 316 stainless steel performs well in various corrosive environments, especially in seawater and chloride-containing environments, and can effectively resist pitting and crevice corrosion.

2. Good high temperature performance. Able to maintain good mechanical properties and oxidation resistance in high temperature environments, suitable for applications in the temperature range of 800-1500°F (427-816°C).

3. High strength and toughness. Shows good strength and toughness under both low and high temperature conditions.

4. Easy to process and weld. With good machinability and weldability, it is suitable for various manufacturing processes.

Specifications and standards

316 stainless steel seamless pipes have a variety of specifications and standards, and common standards include:

ASTM A213: Seamless ferritic and austenitic alloy steel boiler, superheater and heat exchanger tubes.

ASTM A312: Seamless and welded stainless steel pipes.

JIS G3459: Stainless steel pipes.

316 stainless steel seamless pipe

Astm a106 seamless steel pipe

106 seamless steel pipe usually refers to seamless carbon steel pipe of ASTM A106 standard. This pipe is widely used in industrial piping systems under high temperature and high pressure environment. The following is a detailed introduction to ASTM A106 seamless steel pipe:

Standards and grades

ASTM A106 seamless carbon steel pipe is mainly divided into three grades: A, B and C. The chemical composition and mechanical properties of each grade are different, as follows:

Chemical composition (taking grade B as an example)

Carbon (C): ≤0.30%

Manganese (Mn): 0.29-1.06%

Phosphorus (P): ≤0.035%

Sulfur (S): ≤0.035%

Silicon (Si): 0.10-0.35%

Mechanical properties (taking grade B as an example)

Tensile strength: 415-585 MPa

Yield strength: 240 MPa (minimum)

Elongation: ≥30%

Features

High strength: It has excellent tensile strength and yield strength, and can withstand high pressure and high temperature environment.

Good corrosion resistance: It has good corrosion resistance under high temperature and high pressure environment.

Excellent processing performance: easy to cut, weld and form, suitable for various manufacturing processes.

Consistent quality: seamless process ensures uniformity and consistency of pipes, reducing the occurrence of defects and failures.