| 摘要 |
A butterfly valve housing which is to be interposed between two sections of as conduit includes a metallic core body and a covering body of a high-rigidity synthetic plastic material which is molded around the core body to substantially completely encase the same and to form a substantially self-supporting shell around the core body. The core body has and annular portion that bounds an internal opening and two projections which extend radially outwardly from the annular portion. The projections and the annular portion bound transverse passages that are centered on a common axis extending across the internal opening and in use accommodate respective trunnions that support a disc-shaped valve member of the butterfly valve. The covering body has regions which penetrated into these transverse openings to cover the core body within the latter. The core body has two additional projections that are situated between the first-mentioned projections and which have recesses that, during the molding of the covering body around the core body in a molding cavity, receive locating pins that hold the core body in position in the molding cavity. Other locating pins are received in the radially outer ends of the transverse passages during the molding operation to hold the core body in position in the molding cavity.
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