Connecting clamp, connecting apparatus and connecting method

1. Field of the Invention A connecting clamp includes a heating member which surrounds a portion to be connected of a steel pipe and heats the portion to be connected, and a first clamp section and a second clamp section positioned on opposite sides of the portion to be connected and clamping the steel pipe, whereby the portion to be connected is connected by heating the portion to be connected by the heating member while applying pressure to the portion to be connected by the first and second clamp sections. The first and second clamp sections and the heating member are so arranged as to be slidable around the outer surface of the steel pipe from one side of the steel pipe to the other side thereof.