MANUFACTURING METHOD FOR TUBE

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method for a tube capable of increasing the strength in a sealed part of an exhaust pipe. SOLUTION: A glass tube 1 having an exhaust pipe forming part 2 at the end is vertically set and the tip of the exhaust pipe forming part 2 is connected to an exhaust device head 8. A part 6 to be blocked and the vicinity of the part 6 to be blocked of the exhaust pipe forming part 2 are heated with a burner 3 moving up and down. The burner 3 are moved twice or more up and down, a heated and softened part is melted together with the inner surface of the exhaust pipe forming part 2, and a blocking part 4 having sufficient thickness is formed. When the blocking part 4 is still soft, the exhaust pipe forming part 2 is interposed between cutters 5 and cut to form a sealed part 7. The sealed part 7 is annealed to remove strain, and the exhaust pipe 9 is formed.