To provide a method of manufacturing a fin tube, wherein the number of steps for manufacturing the fin tube is reduced to attain efficiency and reduce the manufacturing cost.
The method of manufacturing the fin tube includes: a step in which, by holding the outer periphery of a heat transfer tube by a pair of oppositely facing planar fins, the plurality of pairs of the planar fins are brought into contact with the heat transfer tube and pressurized at a prescribed pressure or higher, in a state where the planar fins are arrayed with prescribed spaces apart in the axial line direction of the heat transfer tube; a step in which, by rotatably driving the heat transfer tube, a frictional heat is generated in the contact face between the planar fin and the heat transfer tube, to perform fusion and welding; and a step in which, by pressing the planar fin against the heat transfer tube during the inertia rotation of the heat transfer tube concurrently with the stoppage of the rotary driving of the heat transfer tube and further by imparting a high upset pressure thereto, braking is applied to the rotation of the heat transfer tube, to bring the planar fin into close contact with the contact face of the heat transfer tube.
FUJITANI YASUYUKI
MORI TADASHI
KISHIKAWA KAORU
Kunio Ueda