FLOW CONTROL VALVE AND MANUFACTURING METHOD THEREFOR

摘要

Provided are: a flow control valve wherein the vicinity of a radial stepped section of a gas passage in a housing has reduced susceptibility to corrosion; and a manufacturing method therefor. The flow control valve (1) is provided with: a housing (2) in which a gas passage (20) is formed, said gas passage comprising a first cylindrical member container (21), a second cylindrical member container (22), and a radial stepped section (23); a first cylindrical member (3) contained in the first cylindrical member container (21); a second cylindrical member (4) contained in the second cylindrical member container (22); and a valve (5) rotatably disposed radially interior to the first cylindrical member (3) and the second cylindrical member (4). The housing (2) is made of cast iron. The surfaces, at least, of the first cylindrical member (3) and the second cylindrical member (4) are made of a highly corrosion-resistant material. A first axial end face (30) and/or a second axial end face (40) have a facing section (401) which faces the radial stepped section (23) in the axial direction. A gas seal structure (61) is disposed between the facing section (401) and the radial stepped section (23).