Title:
METHOD FOR MANUFACTURING RIFLED TUBE
Document Type and Number:
WIPO Patent Application WO/2016/084361
Kind Code:
A1
Abstract:
A method for manufacturing a rifled tube (15) having a plurality of first helical ribs (12) on an inside face thereof and having an outside diameter of 34 mm or less is provided with: a step for preparing a steel pipe having a tensile strength of 600 MPa or less; and a step for cold-drawing the steel pipe using a plug (2) having a plurality of helical grooves (21) and a plurality of second helical ribs (22) each arranged between adjacent helical grooves (21), the plug (2) satisfying expression (1) and expression (2). (1): 0.08 < W × (A – B) × N/(2π × A) < 0.26. (2): 0.83 < S × (A – B) × N/(2 × M) < 2.0. In the expressions, W is the width (mm) of groove bottom faces (210) of the helical grooves (21) in a transverse section of the plug (2), A is the maximum diameter (mm) of the plug (2), B is the minimum diameter (mm) of the same transverse section having the aforementioned maximum diameter, N is the number of second helical ribs (22) in the transverse section, S is the width (mm) of the groove bottom faces (210) in a longitudinal section of the plug, and M is the pitch (mm) of the second helical ribs (22) in the longitudinal section.
Inventors:
NAKASHIMA TAKASHI (JP)
ISEDA ATSURO (JP)
MIKI TAKESHI (JP)
OTSUKA SHUNICHI (JP)
ISEDA ATSURO (JP)
MIKI TAKESHI (JP)
OTSUKA SHUNICHI (JP)
Application Number:
PCT/JP2015/005823
Publication Date:
June 02, 2016
Filing Date:
November 24, 2015
Export Citation:
Assignee:
NIPPON STEEL & SUMITOMO METAL CORP (JP)
MITSUBISHI HITACHI POWER SYS (JP)
MITSUBISHI HITACHI POWER SYS (JP)
International Classes:
B21C3/16; B21C37/20
Domestic Patent References:
WO2009081655A1 | 2009-07-02 |
Foreign References:
JP2005221153A | 2005-08-18 | |||
US20050229667A1 | 2005-10-20 | |||
JPS6172310U | 1986-05-16 | |||
JPH04224013A | 1992-08-13 |
Other References:
See also references of EP 3225319A4
Attorney, Agent or Firm:
ASCEND IP LAW FIRM (JP)
アセンド patent business corporation (JP)
アセンド patent business corporation (JP)
Download PDF: