JIS G3461 Carbon Steel Tubes For Boiler And Heat Exchanger

JIS G3461 STB340 STB410 STB510 Carbon Steel Tubes For Boiler And Heat Exchanger

Material Specification

JIS G3461 is a Japanese industrial standard that specifies the requirements for carbon steel tubes used in boilers and heat exchangers. These tubes are designed to withstand high temperatures and pressures, making them ideal for use in industrial applications. The standard covers three main grades: STB340, STB410, and STB510, each offering different mechanical properties to suit various operational needs.

Key Features

• High Temperature Resistance: Designed to perform efficiently under high-temperature conditions.
• Pressure Resistance: Capable of withstanding high pressure, making them suitable for boiler and heat exchanger applications.
• Versatility: Available in various grades to meet specific application requirements.
• Durability: Offers long service life due to its robust construction.

Chemical Composition

The chemical composition of JIS G3461 carbon steel tubes is crucial for determining their suitability for specific applications. Below is a table presenting the typical chemical composition for each grade:

Element	STB340 (%)	STB410 (%)	STB510 (%)
Carbon (C)	≤ 0.18	≤ 0.20	≤ 0.23
Silicon (Si)	≤ 0.35	≤ 0.35	≤ 0.35
Manganese (Mn)	≤ 0.55	≤ 0.60	≤ 0.60
Phosphorus (P)	≤ 0.030	≤ 0.030	≤ 0.030
Sulfur (S)	≤ 0.030	≤ 0.030	≤ 0.030

Mechanical Properties

The mechanical properties of these tubes are essential for ensuring they can withstand the operational stresses they will encounter. The table below outlines the mechanical properties for each grade:

Property	STB340	STB410	STB510
Tensile Strength (MPa)	≥ 340	≥ 410	≥ 510
Yield Strength (MPa)	≥ 175	≥ 225	≥ 295
Elongation (%)	≥ 35	≥ 30	≥ 25

Steel Grade

The JIS G3461 standard includes three primary grades:

• STB340: Suitable for moderate temperature and pressure applications.
• STB410: Offers higher strength, suitable for more demanding conditions.
• STB510: Provides the highest strength, ideal for the most challenging environments.

Application

JIS G3461 carbon steel tubes are widely used in:

• Boilers: For generating steam and hot water.
• Heat Exchangers: For transferring heat between fluids.
• Power Plants: In various components where high temperature and pressure are factors.
• Petrochemical Industry: For processing and refining applications.

Possible Alternative Grades

While JIS G3461 is a popular choice, there are alternative grades that may be considered depending on specific requirements:

• ASTM A179: Seamless cold-drawn low-carbon steel heat exchanger and condenser tubes.
• DIN 17175: Seamless tubes of heat-resistant steels.
• EN 10216-2: Seamless steel tubes for pressure purposes with specified elevated temperature properties.

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