To control the tube diameter of a work tube to be drawn with excellent accuracy while reducing the cost therefor, to enhance the accuracy during the cutting while reducing the cost therefor.
When a drawing machine draws a work tube 10 by providing the drawing force to the work tube through a die 20a and a plug 20b, deposits (for example, lubricating oil fed from a lubricating oil feed part 28) on a surface of a drawn tube 12 is removed by spraying kerosene or the like by a washing part 30 after the drawn tube is subjected to drawing. The outside diameter of the washed drawn tube 12 is measured by the sensor unit 34, and the drawing speed of the work tube 10 is controlled based on the result obtained by the sensor unit 34. The outside diameter can thus be measured correctly, and the tube diameter of the worked tube can be controlled with excellent accuracy by the measurement of the outside diameter.
Kato Kazunori
Katsuichi Nishimoto
Hiroshi Fukuda
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