Inventor

TSUYAMA YOSHITO

JP3 patents

Patents

3 patents

US4603806AAug 5, 1986

Method of manufacturing metal pipe with longitudinally differentiated wall thickness

NIPPON STEEL CORP45 citations90

US4645893AFeb 24, 1987

Method for manufacturing spiral-welded steel pipe

NIPPON STEEL CORP12 citations66

US4436239AMar 13, 1984

Method and apparatus for manufacturing spiral pipe

NIPPON STEEL CORP11 citations65