Difference between RINA A and RINA B steel plate

RINA A and RINA B are standard strength shipbuilding steel plates certified by the Italian classification society RINA (Registro Italiano Navale). They are primarily used for general structural components in ship hulls and marine constructions where very high impact toughness is not a critical requirement. Both grades share a minimum yield strength of 235 MPa, but their key distinction lies in the specified level of notch toughness at ambient temperatures.

Key Differences

The fundamental difference is the mandatory Charpy V-notch impact test requirement.

RINA A Grade: Has no specified impact test requirement. It is suitable for secondary structures and non-critical areas where the risk of brittle fracture is minimal under normal service conditions.

RINA B Grade: Requires Charpy V-notch impact testing at room temperature (typically +20°C). This ensures a basic level of toughness, making it more reliable than Grade A for primary hull structures and critical components that may experience some dynamic or incidental loads.

RINA A Normal Strength Max Chemical Composition in Hot-rolled

RINA B Normal Strength Max Chemical Composition in Hot-rolled

RINA A Normal strength property in Hot-rolled

RINA B Normal strength property in Hot-rolled