In view of the above-noted state of the art, the object of this invention is to provide a BUTTERFLY VALVES free from sticking at the bearing portions and from an inconvenient flexion of the stem under fluid pressure without requiring the stem to have a large diameter.

To this end, the Butterfly Valves according to this invention comprises a valve housing having tubular portions, a valve stem extending in the tubular portions and carrying a valve closure member rotatable in the valve housing, gland packing portions provided between the stem and the tubular portions to prevent fluid leakage, and bearing portions for the valve stem provided outwardly of the gland packing portions respectively, wherein each of the gland packing portions is divided axially of the valve stem into two sections, and a bearing member is fitted between the valve stem and the tubular portion at a position intermediate between the two sections.

The stem is supported not only by the bearing portions but also by the bearing members each fitted between the divided sections of each gland packing portion. Therefore, the divided gland packing portions protect the bearing members from fluid whose heat would otherwise cause their sticking. The valve stem in this invention is supported at closer intervals than in conventional valves, which helps diminish the flexion of the valve stem due to fluid pressure acting on the valve closure member.Butterfly Valves Thus the invention does not require a large diameter stem, and yet provides excellent sealing and flow characteristic when the valve is completely closed.

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