Kobe Steel Develops High Strength New Plate for Chemical Tank

Kobe Steel announced on Wednesday the firm developed new plate which has high-strength of 550 mega paschal, toughness and weldability for large sphere tank, which delivered for the first time. The firm controlled depression of strength and toughness for plate by optimum addition of alloy and high purity production technology when the plate is vitiated by neat treatment for long time after forming to tank. The firm became commonplace max70 millimeter thick of plate for the first time, which meets users requests which they need thick plate with large tank. The construction of large sphere tank is increasing for preservation of chemical products such as butane or propylene with increasing energy demand in the world. The tank is larger in size and thicker with hoard efficiency and economic efficiency. Users request the plate with over 70 millimeters thick from below 38 millimeters thick. The tank production is needed the post weld removal heating treatment (PWHT). The heating treatment time is going long to about 20 hours from about 8hours with thicker plate. PWHT changes micro anatomy of plate and vitiates strength and toughness with longer heating time. In the past, many alloy addition can control the depression, but vitiates weldability.