PURPOSE: To prevent seizure by providing nozzles with which lubricant is jetted toward rotary disks on the outside part of cannon with which a billet is introduced to a piercing roll in the piercing device of the manufacturing line for seamless steel tube.
CONSTITUTION: In the piercing device of the manufacturing line for seamless steel tube, the cannon 28 with which the billet 12 is introduced toward the piercing rolls 22a, 22b and the rotary disks 24a, 24b which are adjacently arranged to the piercing roll 22 and with which the billet 12 worked into a hollow piece 14 is introduced are contained, the jet nozzles 42a, 42b for supplying lubricant to the rotary disks 24 are provided on the outside part of the cannon 28 and the device is constituted so as to supply lubricant to the rotary disk 24 in the vicinity of the contact position with the billet 12. In this way, seizure between the billet 12 and the rotary disks 42a, 42b can be prevented.
YOKOYAMA TAKASHI
SAITO NORIYUKI
SASA TOSHIO
