Title:
BUTTERFLY VALVE AND MANUFACTURING METHOD THEREFOR
Document Type and Number:
Japanese Patent JP2002346671
Kind Code:
A
Abstract:
To provide a butterfly valve having high productivity and excellent shape accuracy by reducing the number of molding man-hours of the inner tube of the butterfly valve.
A peripheral wall of a round tubular material tube is bent and formed, and a hydraulic forming tube 4 in which a plurality of wavy projections 40, 40... are provided in the longitudinal direction at every pitch is manufactured. This hydraulic forming tube 4 is cut in the shaft cross section at neat the apex of each the wavy projection 40, 40..., the half parts of the wavy projections 40, 40... are remained on both sides of a short tubular body, and these comprise an inner tube 1 as gasket seats 10, 10... whose diameters are expanded in a circular plate shape.
Inventors:
NAKANISHI NOBUYUKI
TANAKA TAKAMI
KAWAMURA HIDEO
SADAYAMA SEISHO
IWASAKI ISAO
TANAKA TAKAMI
KAWAMURA HIDEO
SADAYAMA SEISHO
IWASAKI ISAO
Application Number:
JP2001154608A
Publication Date:
December 03, 2002
Filing Date:
May 23, 2001
Export Citation:
Assignee:
KURIMOTO LTD
YAMAMOTO SUIATSU KOGYOSHO KK
YAMAMOTO SUIATSU KOGYOSHO KK
International Classes:
F16K27/02; B21D26/033; B21D26/035; B21D26/047; B21D51/18; F16K1/22; F16K27/00; (IPC1-7): B21D51/18; B21D26/02; F16K1/22; F16K27/02
Attorney, Agent or Firm:
Tono Kono
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