| 摘要 |
PURPOSE:To prevent resonance vibration of a valve and damage of carbon packings, by providing a plurality of partitioning plates in the axial direction of a valve rod and partitioning the inside so as to form a plurality of hollow chambers in the main steam control valve for a steam turbine driving a pump in a cooling system when a nuclear reactor is isolated. CONSTITUTION:A main steam control valve 30, being formed into hollow construction, provides in its internal contour part a plurality of partitioning plates 43 at a distance apart in the axial direction, forming a plurality of hollow chambers. The valve 30 provides in its upper part, in which the valve 30 is connected with a valve rod 25, a balance hole 44 which guides steam, leaking from a clearance between the internal contour side of a sleeve 42 mounted to an upper valve structure 29 and the peripheral side of the valve 30, to a steam outflow side of the main steam control valve. A plurality of carbon packings 26 are piled together toward the axial direction of the valve rod 25 in the internal contour side of a bush 39 and fixed to an end part of the bush by a screwing plug. |
