Carbon steel seamless pipe for ships refers to a seamless pipe material used in ship construction and maintenance. Its main feature is that it is made of carbon steel, which has high strength and corrosion resistance. GB5312-85 is a standard promulgated by the China Standardization Organization, which stipulates the technical requirements and test methods for carbon steel seamless pipes for ships.
Chinese standard for ships:
Carbon steel seamless pipes for ships (GB5213-85) are carbon steel seamless pipes used to create Class I pressure-resistant piping systems, Class II pressure-resistant piping systems, boilers and superheaters for ships. The working temperature of the wall of carbon steel seamless pipes does not exceed 450°C, and the working temperature of the wall of alloy steel seamless pipes exceeds 450°C.
Carbon steel and carbon-manganese steel seamless steel pipes for ships (GB5312-1999): mainly used for grade I and II pressure-resistant pipes for ship boilers and superheaters. Representative materials are 360, 410, 460 steel grades, etc.
American standard for ships:
ASTM A106/ASME SA106 seamless pressure pipe is commonly used in the construction of oil and gas refineries, power plants, petrochemical plants, boilers, and ships where the piping must transport fluids and gases that exhibit higher temperatures and pressure levels.
Technical requirements for carbon steel seamless pipes for ships:
1. Material requirements: The material requirements for carbon steel seamless pipes are #20, #25, and #30 steel. Among them, #20 steel has better corrosion resistance and is suitable for ships with harsh operating environments.
2. Manufacturing method: Carbon steel seamless pipes for ships use cold-drawn or hot-rolled seamless manufacturing processes. After being made, the steel pipes need to be pickled, painted and other surface treatments are carried out.
3. Physical properties: The physical properties of carbon steel seamless pipes for ships must meet the requirements specified in the standard, including tensile strength, yield strength, elongation and other indicators.
4. Chemical composition: The chemical composition of carbon steel seamless pipes for ships must meet the requirements of the standard, and the carbon content should be between 0.17% and 0.24%.
Test methods for carbon steel seamless pipes for ships:
1. Appearance inspection: Check whether there are cracks, defects, oxide scale, etc. on the surface of the steel pipe.
2. Chemical composition analysis: Use chemical analysis methods to detect whether the chemical composition of the steel pipe meets the standard requirements.
3. Mechanical performance test: including tensile test, flattening test, hydraulic test, bending test, etc., to detect whether the physical properties of the steel pipe meet the standard requirements.
For example: Carbon steel seamless steel pipes should be subjected to hydraulic pressure tests one by one. The pressure resistance time of the hydraulic pressure test should not be less than 10 seconds. The steel pipes should not leak or seep. With the approval of the ship inspection department, non-destructive inspection methods are allowed to be used instead of hydrostatic tests.
Carbon steel seamless pipes for ships are an indispensable material in the process of ship construction and maintenance. Strict control of its quality and technical requirements is crucial to the safe operation of ships.
