| 摘要 |
PURPOSE:To have full closing of a steam control valve smoothly when it should occur quickly by actuating a damping valve as component of this steam control valve, and at the same time by closing rapidly an equalizer valve which is also a component member of said steam control valve. CONSTITUTION:This steam control valve includes an oil-hydraulic cylinder 2 to drive valve element 6 installed inside the valve casing 1, a damping valve 3 to exhaust quickly the oil out of said cylinder 2, a pilot valve 10 ato supply and exhaust the oil to/from the lower part of the cylinder 2 in accordance with control signals, and an oil relay 4 to supply and exhaust the oil to/from the lower part of said damping valve 3. Thereto are also added a solenoid valve 5 to change over the operating position of the oil relay 4, an equalizer valve 7 to be installed on the piping which connects a chamber in the upper part of the valve element 6 to downstream the valve, and a solenoid valve 8 to perform opening/closing of this valve 7. On the piping between the equalizer valve 7 and solenoid valve 8, another oil relay 9 is interposed, which is controlled according to the magnitude of the supply oil pressures to the lower part of the damping valve 3 of the above mentioned oil relay 4. Thus the damping valve 3 and equalizer valve 7 can operated interlockedly. |
