To provide a manufacturing method of a tube having high dimensional accuracy capable of favorably manufacturing a tube having a large shrinkage ratio from a stock tube of one and the same size over the extensive range of request sizes of the tube, manufacturing tubes of different sizes, and manufacturing tubes at high efficiency.
In the manufacturing method of the tube having high dimensional accuracy in which a plug 1 is inserted in a tube 3, and the tube is punched by a die 2, a plurality of dies of different working sizes which are arranged in series in multiple stages in the working direction are used for the die. The tube can be efficiently punched without seizure by feeding a lubricant to an inner surface and/or an outer surface of the tube during the working (the tube between the die stages).
NAGAHAMA TAKUYA
SAKATA TAKASHI
SAKAGUCHI MASAYUKI
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