To perform the kneading of a continuous strip member with the consumption of a small amount of energy and also prevent kneading time from varying under the influence of a seasonal factor by heating the continuous strip member when it passes through a hot water tank and drying it using a specific dryer.

A strip member 1 is guided to a hot water tank 3 with the help of a belt conveyor. The hot water tank 3 is operated to keep the strip member 1 under a water level using a holding roll and is constantly rocked by a rocking roll. In addition, the strip member 1 is guided to a pair of heating drums 5 through the belt conveyor. The paired heating drums 5 are of such a type that hot water is loaded inside. The hot water is set at 90°C, for example, and this temperature is maintained. Further, another heating drum 5 is provided behind the heating drum 5 and is operated for assisting in the heating and drying process. Next, the strip member 1 is caused to pass through at least, a single dryer 4 for drying process and then is loaded into a roll-type kneading machine 2 for kneading. Thus it is possible to ensure the positive preheating of the strip member 1.