Title:
DEVICE AND METHOD FOR MANUFACTURING SEAMLESS TUBE
Document Type and Number:
Japanese Patent JP3036356
Kind Code:
B2
Abstract:
PURPOSE: To manufacture a seamless tube without the occurrence of a defect even in the case of a high expansion ratio.
CONSTITUTION: A billet B is fed in the axial length direction, is rotated helically and is moved by the rotations of both main rolls 1. And, a plug 2 with specific dimensions and a shape is intruded into the billet B, a hollow shell H is drawn, and piercing whose expansion ratio is 1.15 or over is stably performed. For the shape and dimensions of the plug 2, the sum of the length of the rolling part L1 of the plug and a plug reeling part L2 is two to four times the diameter Bd of the billet B, L1/L2 is 0.1 to 3.0, and a difference idle obtained by subtracting an angle contained by the skew roll surface and a pass center from an angle θp contained by a plug surface and the pass center is -0.65° to 0.2°.
Inventors:
Tomio Yamakawa
Isso Shimoda
Isso Shimoda
Application Number:
JP12925394A
Publication Date:
April 24, 2000
Filing Date:
June 10, 1994
Export Citation:
Assignee:
SUMITOMO METAL INDUSTRIES,LTD.
International Classes:
B21B19/04; B21B19/08; B21B25/00; B21B27/02; (IPC1-7): B21B19/04; B21B25/00
Domestic Patent References:
| JP4143004A | ||||
| JP1181905A | ||||
| JP6466006A | ||||
| JP5944927B2 |
Attorney, Agent or Firm:
Norio Kawano