... level, normally used for shipbuilding, marine structures. special 1, Welding term, low-alloy steel and high strength steel 490Mpa level ... used for shipbuilding, marine structures, steel structures, bridges, chemical welding equipment, etc.2,PackagingWire SizeSpool SizeNet WeightΦ1.0~1 ... Preheating before welding to 150-300 °C, PWHT 700-740 °C tempered by the need to deal with Flux Cored Welding Wire ...