Crane pedestal foundations in offshore engineering are characterized by high-strength base materials

thick-section plates

and highly rigid structures

making them susceptible to cold/hot cracking and structural distortion during welding. For a specific project involving an EH36 high-strength steel pedestal (dimensions: 2001 mm × 2169 mm × 19135 mm

weight: 45.945 t

plate thickness: 42 mm)

this study developed a flux-cored arc welding (FCAW) process using ceramic backing for single-side welding with double-sided formation (SSW-DSF). This approach eliminates the need for back gouging

improves welding efficiency

and reduces secondary heat-induced deformation. Key process parameters： interpass temperature control (≤230 ℃)

maximum heat input (≤13 kJ/cm)

and root pass current limitation (≤200 A)—were optimized to mitigate cracking risks and ensure joint integrity. Multi-pass welding strategies were employed to minimize residual stresses and angular distortions. The welded joints passed all non-destructive testing (VT

MT

UT) and mechanical tests (tensile

bend

impact

hardness)

meeting project specifications. Practical implementation confirmed that the proposed technology ensures both weld quality and dimensional accuracy of the crane pedestal. This work provides valuable technical guidance for similar thick-plate

high-strength steel welding applications in offshore structures.