Description
JIS G3429 STM11 STH12 STH21 STH22 STH31 Gas Cylinder Tube
Introduction
The JIS G3429 standard specifies the requirements for gas cylinder tube made from various steel grades. These tubes are essential for the safe storage and transportation of gases under high pressure. This article will cover the material specifications, key features, chemical composition, mechanical properties, steel grades, applications, and possible alternative grades.
Material Specification
The gas cylinder tubes under JIS G3429 are manufactured from high-quality carbon steel and alloy steel, ensuring durability and safety under pressure.
Key Features
- High Strength: Designed to withstand high pressure.
- Corrosion Resistance: Suitable for various environments.
- Weldability: Can be easily welded for fabrication.
- Lightweight: Facilitates easier handling and transportation.
Chemical Composition
Steel Grade | C (%) | Si (%) | Mn (%) | P (%) | S (%) | Cr (%) | Ni (%) | Mo (%) |
---|---|---|---|---|---|---|---|---|
STM11 | 0.12 | 0.15 | 0.60 | 0.025 | 0.025 | 0.30 | 0.30 | 0.10 |
STH12 | 0.12 | 0.15 | 0.60 | 0.025 | 0.025 | 0.30 | 0.30 | 0.10 |
STH21 | 0.15 | 0.20 | 0.70 | 0.025 | 0.025 | 0.40 | 0.40 | 0.15 |
STH22 | 0.15 | 0.20 | 0.70 | 0.025 | 0.025 | 0.40 | 0.40 | 0.15 |
STH31 | 0.20 | 0.25 | 0.80 | 0.025 | 0.025 | 0.50 | 0.50 | 0.20 |
Mechanical Properties
Steel Grade | Yield Strength (MPa) | Tensile Strength (MPa) | Elongation (%) | Hardness (HB) |
---|---|---|---|---|
STM11 | 245 | 400-510 | 20 | 120 |
STH12 | 245 | 400-510 | 20 | 120 |
STH21 | 295 | 490-590 | 18 | 130 |
STH22 | 295 | 490-590 | 18 | 130 |
STH31 | 345 | 540-640 | 16 | 140 |
Steel Grade
The JIS G3429 standard includes several steel grades, each designed for specific applications and pressure requirements. The main grades are STM11, STH12, STH21, STH22, and STH31.
Application
Gas cylinder tube are widely used in various industries, including:
- Medical: For oxygen and other medical gases.
- Industrial: For welding and cutting gases.
- Chemical: For the storage of reactive gases.
- Energy: For natural gas and other fuel gases.
Possible Alternative Grades
While the JIS G3429 grades are widely used, there are alternative grades that may be considered based on specific requirements:
- ASTM A519: For seamless carbon and alloy steel mechanical tubing.
- EN 10216: For seamless steel tubes for pressure purposes.
- ISO 9809: For high-pressure gas cylinders.