CCS A and CCS B steel plates are common grades of shipbuilding steel from the China Classification Society (CCS), differing mainly in toughness levels for various temperatures, both offering good strength, weldability, and corrosion resistance for ship hulls, with Grade A being suitable for normal temperatures and Grade B offering better performance at lower temperatures (0°C) and generally used for more critical structural parts.
Chemical Composition of CCS A
|
Element |
CCS A Max % |
Element |
CCS A Max % |
|
C |
0.21 |
Ni |
|
|
Mn |
2.5*C MIN |
Mo |
|
|
Si |
0.50 |
Al |
|
|
S |
0.035 |
Nb |
|
|
P |
0.035 |
V |
|
|
Cu |
|
Ti |
|
|
Cr |
|
N |
|
Chemical Composition of CCS B
|
Element |
CCS B Max % |
Element |
CCS B Max % |
|
C |
0.21 |
Ni |
|
|
Mn |
0.80 |
Mo |
|
|
Si |
0.35 |
Al |
|
|
S |
0.035 |
Nb |
|
|
P |
0.035 |
V |
|
|
Cu |
|
Ti |
|
|
Cr |
|
N |
|
Mechanical properties of CCS A
|
Grade |
Thickness |
Yield Strength |
Tensile Strength |
Elongation |
Impact Energy |
|
(mm) |
MPa (min) |
MPa |
% (min) |
(KV J) (min) |
|
|
|
|
|
|
20 degree |
|
|
CCS A |
8-240 |
235 |
400-520 |
22 |
|
Mechanical properties of CCS B
|
Grade |
Thickness |
Yield Strength |
Tensile Strength |
Elongation |
Impact Energy |
|
(mm) |
MPa (min) |
MPa |
% (min) |
(KV J) (min) |
|
|
|
|
|
|
0 degree |
|
|
CCS B |
8-240 |
235 |
400-520 |
22 |
27J |
Key Differences & Properties:
CCS Grade A: The basic grade, designed for normal temperature applications (around 20°C).
CCS Grade B: Offers enhanced impact toughness at lower temperatures (0°C) compared to Grade A, making it more versatile.
Strength: Both have similar minimum yield strength (~235 MPa) and tensile strength (~400-520 MPa).
Applications: Used in ship hulls, cargo vessels, tankers, and other marine structures needing good strength, toughness, and weldability.
In essence: Think of CCS A as the standard, while CCS B is a slightly tougher, more versatile upgrade for marine environments where temperatures can drop, ensuring structural integrity in harsher conditions.
