PURPOSE: To contrive to make the quality of a sintered ore uniform, by changing an igniting position at each part of a pallet along its widthwise direction corresponding to the upper surface of a raw material to be sintered being charged in the pallet along the moving direction of said pallet.

CONSTITUTION: In the process of moving a pallet 1 along the arrow between driving and idling sprockets 2 and 3, said pallet is packed with a flooring ore and a raw material to be sintered from hoppers 4, 5, respectively. Said packing layer is ignited in an ignition oven 6 and held hot in a heat-retaining oven 7. On the other hand, air is sent from the upper surface of the pallet to its lower part by the suction force of each wind box 8 through a common duct. Hence, the packing layer is sintered with the movement of the pallet. In the oven 6, burners 61 in lines of 20, 5 with the same intervals d, l along the widthwise and moving directions, respectively, of the pallet, constituted in the same way, are provided on the plane of a wind tunnel in parallel with the upper surface of said packing layer. An operational controlling part 10 changes the igniting position of one burner among five of the line of burners along the moving direction of the pallet in a manner such that the distribution of temp. is made uniform by a pallet counter 12 and a thermometer 9 corresponding to each line of burners at the downstream side of the igniting position.