Three large blast furnaces of NKK have been shifted to the operation without liquid fuel one after another since January, 1980, and the oil-less operation of all blast furnaces was finally achieved in April, 1980. Fukuyama No. 3 Blast Furnace (3223m3), has been operated with increased blast volume and higher blast temperature in order to solve operational problems and achieve improved operation. Although increased slips and fluctuations in blast pressure have been often observed in the operations when the flame temperature is high, all furnaces have been in smooth operation owing to the proper gas distribution control and furnace heat control. By the calculations based on operational results, a productivity of as high as 2.3t/m3/d can be expected on a monthly averaged value in all-coke operation.