本发明是一种F级超高强海洋工程用特厚板的淬火工艺，淬火温度为Ac₃+(10-50)℃，淬火速度为0.035-0.050m/s，淬火后温度≤50℃，淬火冷速为20-35℃/s，淬火总水量为15000-18000m³/h，水比为1.10-1.35；淬火冷却水高压段为2组缝隙喷嘴加5组高密喷嘴，冷却水压力为0.7-0.8MPa，淬火冷却水低压段为12组高密喷嘴，冷却水压力为0.3-0.4MPa。本发明可有效提高F级超高强度海洋工程用特厚板的心部淬透性、沿板厚方向的组织均匀性，保证钢板强度和低温冲击韧性，避免采用传统淬火工艺引起的表面晶粒粗化和瓢曲、扣翘等板形问题。

The invention discloses a quenching technology of an F-grade extra-thick plate for ultrahigh-strength ocean engineering. The quenching technology is characterized in that the quenching temperature is (Ac₃ + (10 to 50)) DEG C; the quenching speed is 0.035 to 0.050 m/s; the temperature after quenching is 50 DEG C or below; the quenching cooling speed is 20 to 35 DEG C/s; the quenching total water amount is 15000 to 18000 m³/h; the water ratio is 1.10 to 1.35; a quenching cooling water high pressure section comprises two groups of gap nozzles and five groups of high-density nozzles; the cooling water pressure is 0.7 to 0.8 MPa; a quenching cooling water low pressure section comprises twelve groups of high-density nozzles; and the cooling water pressure is 0.3 to 0.4 MPa. According to the quenching technology, the core hardenability and structure homogeneity in the plate thickness direction of the F-grade extra-thick plate for ultrahigh-strength ocean engineering can be effectively improved, the strength and low temperature impact toughness of the steel plate are guaranteed, and plate shape problems like surface grain coarsening, buckling and warping due to the adoption of a traditional quenching technology are avoided.