Difference between BV D620 and BV E620 steel plate

BV D620 and BV E620 are high-strength structural steel plates certified by Bureau Veritas (BV) for specialized, heavy-duty marine and offshore applications, such as ice-class vessels, offshore wind foundations, and high-stress structural nodes. Both grades share an ultra-high minimum yield strength of 620 MPa, providing exceptional load-bearing capacity and enabling significant structural weight reduction. Their key distinction is not strength, but their guaranteed low-temperature toughness, defined by their prefix.

Key Differences

The core difference lies in their impact toughness testing temperature, a critical factor for operational safety in cold climates. BV D620 is required to maintain adequate impact energy (resistance to brittle fracture) at a test temperature of -20°C. Conversely, BV E620 must meet these stringent toughness requirements at a significantly lower temperature of -40°C. This makes E620 the essential material for structures operating in polar regions or severe arctic conditions where failure due to brittle fracture is a major risk. Achieving this enhanced low-temperature performance in E620 necessitates more sophisticated metallurgy, stricter process control (like thermo-mechanical rolling), and often results in slightly different weldability and fabrication characteristics compared to D620. Therefore, the choice is dictated by the service environment: Select BV D620 for very high-strength applications in moderate or cold (down to -20°C) climates; choose BV E620 for the same strength but where guaranteed performance in extreme arctic cold (below -40°C) is non-negotiable.

RINA D620 extra high Strength Chemical Composition in Tempering and Quenching

RINA E620 extra high Strength Chemical Composition in Tempering and Quenching

RINA D620 extra high strength property in Tempering and Quenching

RINA E620 extra high strength property in Tempering and Quenching