Oxyfuel cutting excels with high-yield steels like S690QL due to its ability to cleanly profile thick quenched-and-tempered plates (50-200mm) without excessive heat distortion or edge cracking. This thermal process delivers straight, square cuts ideal for heavy structural fabrication where plasma reaches its limits on material over 40mm thick.
Why Oxyfuel Dominates Thick High-Strength Steels
S690QL's minimum 690 MPa yield strength and through-hardened microstructure demand controlled preheat (100-175°C depending on thickness) to prevent hydrogen cracking during profiling. Oxyfuel torches maintain consistent kerf width up to 260mm depth while minimizing the heat-affected zone (HAZ) compared to plasma on heavy sections. The oxygen jet produces sharp, dross-free edges ready for immediate welding without extensive grinding.
Precision for S690QL and Beyond
Modern CNC oxyfuel tables achieve ±1mm positional accuracy across 4x12m plates, nesting multiple crane boom segments or offshore platform legs efficiently. For S690QL1 (-60°C impact grade), preheating prevents brittle fracture initiation at cut edges, while post-cut normalization restores base metal properties in critical lifting lugs.
Heavy Fabrication Applications
UAE shipyards and oil rig fabricators use oxyfuel for S690QL pressure vessel skirts, wind tower base flanges, and mining truck chassis where weight savings justify the premium alloy. The process cuts 100mm plate at 300-500mm/min—3x faster than waterjet with 40% lower operating costs per linear meter.
UAE Processing Excellence
Services like oxyfuel cutting services | precision steel plate processing uae integrate S690QL plate supply with certified cutting to EN 1090 standards, complete with dimensional reports and PMI verification. Sharjah suppliers deliver pre-profiled components direct to weld bays, slashing fabrication lead times by 60%.