PURPOSE: To heat the upset portion of an upset pipe and the piping body in the same heating time by providing a means of heating the upset portion and a means of centering the charging position of the upset pipe in a heat treatment furnace.
CONSTITUTION: An upset pipe 2 is charged by a roller conveyer 3 from the outside into the inside of a heat treatment furnace 1 and then orderly fed in a direction crossed to the longitudinal direction by means of a feeder 4. Hot air is sent into the furnace 1 from a burner port 5 and a high-temperature gas is sent through a duct 8 from a suction blower 7 into nozzles 6 to heat the upset portion 2b. On the other hand, also, on the feed line outside the furnace 1, photoelectric detectors 9 and 10 to be shielded over a minimum length of l1 and a photoelectric detector 11, together with the detector 9, to be shielded over a maximum length of l2 are provided. Also, a pulse generator 13 is provided at an optional position. By these devices, a reversible motor 14 is controllably driven, an end stopper 17 is transferred to a given position, and the upset pipe 2 is charged into an exact position.
KITAYAMA HIDEO
KOBAYASHI HIDEKI
CHUGAI RO KOGYO KAISHA LTD