What is the difference between marine steel plate ccs-a and ordinary Q235-B steel plate?
Although the steel plates CCS A and Q235 B for marine use may seem to have similar yield strengths, CCS A is a specially produced and certified steel specifically for manufacturing ship structures, while Q235-B is a general-purpose carbon structural steel. There are fundamental differences in the execution standards, chemical composition, and performance requirements between the two, and they cannot be used interchangeably at will.
| CCS A (Structural Steel for General Strength Hulls) | Q235 B (Ordinary Carbon Structural Steel) | |
| Core definition | Produced in accordance with the standards of the China Classification Society, this is a type of hot-rolled steel plate specifically used for shipbuilding and offshore facilities. | Produced in accordance with the national standard GB/T 700, this steel is used for general structures such as buildings, bridges, and machinery. |
| Standards | China Classification Society "Material and Welding Specifications" | GB/T 700-2006 "Carbon Structural Steel" |
| Certification | It must undergo factory approval and product inspection by the China Classification Society (or other international classification societies), and there must be strict third-party certification. | Generally, no special third-party certification is required. The steel mill can supply the goods in accordance with national standards. |
| Chemical composition | The control of harmful elements such as P (phosphorus) and S (sulfur) is more stringent, and the upper limit requirements are lower (please refer to the end note for details) | The component range is relatively broad, and the upper limit requirements for P and S content are higher than those of CCS A. |
| Mechanical properties | Yield strength ≥ 235 MPa Tensile strength 400 - 520 MPa Impact toughness requirement: tested at 0℃ to ensure certain low-temperature toughness |
Yield strength ≥ 235 MPa (thickness ≤ 16mm) Tensile strength 370 - 500 MPa Impact toughness requirement: tested at 20℃ room temperature |
| Core difference | Design purpose and safety margin. To accommodate the complex loading, welding and marine environment of ships, higher requirements are imposed on the toughness, weldability and corrosion resistance of the steel. The corrosion resistance is superior to Q235B. | General structure and cost. Meet the performance requirements of conventional buildings and machinery, with economy being the primary consideration. |
Detailed Explanation of Core Differences
Security and authentication are crucial
The most fundamental difference of CCS-A lies in the fact that it has been strictly certified by the classification society. This means that from the steelmaking process, chemical composition, mechanical properties to the production process, all are subject to the supervision of a third-party institution, ensuring that each steel plate is stable and reliable, capable of meeting the safety requirements of the ship's structure in harsh sea conditions.
Toughness at low temperatures
Although the lower limit of yield strength for both is the same, Q235B only undergoes impact tests at a normal temperature of 20℃, while CCS-A requires the tests to be conducted at 0℃. This difference is crucial for ships navigating in cold waters, as it can effectively prevent the steel plates from experiencing brittle fractures at low temperatures.
Differences in corrosion resistance
A study compared the corrosion behaviors of two types of steel in freshwater environments and found that after a period of 7 years of exposure, CCS-A exhibited slightly better corrosion resistance than Q235B. This is due to its stricter component control. For ship bodies that are constantly exposed to damp and corrosive environments, this difference will accumulate into a significant advantage over time.
who choose us?
We promise to provide genuine and verifiable factory certification certificates from the China Classification Society (CCS A steel) and product inspection certificates along with the goods. This is a crucial requirement for the shipyard's warehouse acceptance process.
Common specifications (CCS A 6-40mm) are in ample supply and can be cut to any length as per customer requirements. This feature helps shipyards reduce waste from leftover materials and lower procurement costs.
Based on the size of the order and the history of cooperation, we can offer competitive payment terms to help the shipyard optimize its cash flow.
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Choose YUXIN steel group, and what you purchase is not merely the steel plates, but also a complete warranty system and a sense of responsibility.
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Tianjin, China
Phone Number
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FAQ
01.How are the names of the ship plates determined? For example, what does CCS A mean?
A: Indicates that the strength level is of general strength. The general strength steel plates are divided into four grades: A, B, D, and E. The main difference lies in the test temperature for impact toughness (grade A at 0°C, grade B at 20°C, grade D at -20°C, and grade E at -40°C).
02.When purchasing the ship plates, what documents can you provide?
Traceability: The furnace number and batch number on the certificate must be consistent with the physical markings on the steel plate.
Data: It must include actual measured data such as chemical composition, mechanical properties (yield, tensile strength, impact value), etc.
03.What is the minimum order quantity?
04.Can you provide cutting and processing services?
China one-stop steel processing procurement
Through years of understanding and precipitation of steel, Yuxin Group has now become a mature steel processing and manufacturer, providing various products for many construction companies and steel structure companies around the world. Thanks to Yuxin Group's professionalism and integrity, it has become a world-renowned enterprise.
