A batch annealing furnace for coils configured to anneal a coil in which a steel sheet is wound, the batch annealing furnace comprising: a coil support base on which an end face of the coil is mounted and that supports the coil with an axis of the coil being upright; an inner cover that covers an entire body of the coil mounted on the coil support base; and a cooling pipe that extends downward from an upper part of the inner cover to a cavity of an inner peripheral part of the coil mounted on the coil support base and cools the coil from an inner surface side by passing a coolant through inside of the cooling pipe, wherein the cooling pipe comprises: an introduction pipeline that introduces the coolant from the upper part of the inner cover toward the coil support base; and at least a return pipeline that returns the coolant toward the upper part of the inner cover; characterized in that the cooling pipe further comprises: at least a curved pipeline formed as a semispherical shape convex downward, that changes a direction of flow of the coolant introduced into the introduction pipeline toward the upper part of the inner cover, the return pipeline returning the coolant of which direction of flow has changed by the curved pipeline. a coil support base on which an end face of the coil is mounted and that supports the coil with an axis of the coil being upright; an inner cover that covers an entire body of the coil mounted on the coil support base; and a cooling pipe that extends downward from an upper part of the inner cover to a cavity of an inner peripheral part of the coil mounted on the coil support base and cools the coil from an inner surface side by passing a coolant through inside of the cooling pipe, wherein the cooling pipe comprises: an introduction pipeline that introduces the coolant from the upper part of the inner cover toward the coil support base; and at least a return pipeline that returns the coolant toward the upper part of the inner cover; characterized in that the cooling pipe further comprises: at least a curved pipeline formed as a semispherical shape convex downward, that changes a direction of flow of the coolant introduced into the introduction pipeline toward the upper part of the inner cover, the return pipeline returning the coolant of which direction of flow has changed by the curved pipeline. an introduction pipeline that introduces the coolant from the upper part of the inner cover toward the coil support base; and at least a return pipeline that returns the coolant toward the upper part of the inner cover; characterized in that the cooling pipe further comprises: at least a curved pipeline formed as a semispherical shape convex downward, that changes a direction of flow of the coolant introduced into the introduction pipeline toward the upper part of the inner cover, the return pipeline returning the coolant of which direction of flow has changed by the curved pipeline. at least a curved pipeline formed as a semispherical shape convex downward, that changes a direction of flow of the coolant introduced into the introduction pipeline toward the upper part of the inner cover, the return pipeline returning the coolant of which direction of flow has changed by the curved pipeline.