Title:
MANUFACTURING METHOD OF SEAMLESS TUBE
Document Type and Number:
Japanese Patent JP2001162307
Kind Code:
A
Abstract:
To provide a manufacturing method of a seamless tube to effectively suppress generation of flaws on an inner surface without generating any defective bite in the Mannesmann pushing and boring method using a material such as free-cutting steel easy to degrade the internal material quality and high alloy steel difficult to work.
In the manufacturing method of the seamless tube to allow a cast ingot of circular transverse section to bite a skew mill roll and bore it by a boring plug, the skew mill roll is rotated at the peripheral velocity below 4.5 m/second and the back-pressure is applied to the cast ingot by a pusher until the cast slab is stably bitten by the skew mill roll.
Inventors:
KATSUMURA TATSURO
ARIIZUMI TAKASHI
AZUMA SHOZO
ARIIZUMI TAKASHI
AZUMA SHOZO
Application Number:
JP34651399A
Publication Date:
June 19, 2001
Filing Date:
December 06, 1999
Export Citation:
Assignee:
NIPPON KOKAN KK
International Classes:
B21B19/04; C22C38/00; C22C38/50; (IPC1-7): B21B19/04; C22C38/00
Attorney, Agent or Firm:
Takehiko Suzue (5 outside)
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