To provide a drawing method of a tube which can improve a work efficiency from a step to insert a mandrel into a mother tube to a step to separate the mandrel from the mother tube.
The drawing method of a tube comprises a step to insert the mandrel 200 into the mother tube 100, a step to draw the mother tube 100 with the mandrel inserted through a die 10, and a step to separate the drawn mother tube 100 and the mandrel 200. In the inserting step of the mandrel 200, a squeezed portion 110 of the mother tube 100 squeezed at its end is inserted into the die 10 to hold the position of the mother tube 100. In that state the top of the mandrel 200 is pulled by a drawing carriage 20 and the mandrel 200 is inserted into the mother tube 100. In the separation step of the mandrel 200 and the mother tube 100, a stopper 220 is prepared at the tail end of the mandrel 200, and the drawing carriage 20 is moved in the drawing direction of the mother tube 100. Thereby, the stopper 220 comes to touch with the die 10 and retains the position of the mandrel 200. The drawing carriage 20 is further moved in the drawing direction to draw the mother tube 100 over the mandrel 200.
TAMAE HIROAKI
SHIMIZU KENICHI
Hidemi Aoki
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