VALVE FOR POWDER

摘要

Disclosed is a valve for powder wherein powder is prevented from gathering in the valve without complicating or enlarging an apparatus, and the valve can endure high-pressure feed. A valve element (22) supported by a valve stem (25) is provided in a valve casing (21), the valve element (22) is equipped with a spherical outer surface (27) which touches the valve seat (23) of the valve casing (21) to close the valve. The valve element (22) is provided with a circulation hole (26) intersecting the valve stem (25) perpendicularly so that the valve can be opened through the circulation hole (26) when the valve element (22) rotates in any direction from valve close state. The circulation hole (26) is opened over the full length on the back (22b) side of the valve element (22). With such an arrangement, advantages of a ball valve, i.e. full bore and high rigidity, can be ensured and the pressure of powder flowing through the circulation hole (26) spreads toward the inner surface of the valve casing (21). Consequently, powder which is apt to gather near the inner surface of the valve casing (21) can be blown off by jet flow of powder and removed. When the orientation of the valve element (22) is changed, powder can be removed on the opposite sides of the valve stem (25).