1, in the closed position, the valve body is mechanically pressed by the valve stem and tightly pressed on the valve seat.
2, when turning the handwheel counterclockwise the valve stem is reversed and its bottom angle plane causes the ball to disengage from the valve seat.
3, the stem continues to ascend and interacts with the guide pin in the stem spiral so that the ball begins to rotate without friction.
4, until the fully open position, the stem reaches the limit position, and the ball rotates to the fully open position.
1, turn the handwheel clockwise when the valve closes. The stem begins to fall and the ball begins to rotate away from the seat.
2, continue to rotate the handwheel, the stem is inserted in the spiral groove in the guide pin role, so that the stem and gate simultaneously rotating 90 degrees.
3, when it is about to close, the gate has been rotated 90 degrees without contact with the valve seat.
4, in the last few turns of the handwheel, the angle plane at the bottom of the valve shaft is mechanically wedged against the compression sphere, making it tightly pressed against the valve seat to reach full seal.
[Valve structure drawing]
|Design standard||API 600、ASME B16.34、DL/T 531、JB/T3595|
|Structural length||DL/T 531、ASME B16.10、GB/T 12221|
|Connection standard||DL/T 531、JB/T3595、ASME B16.25|
|Pressure test||API 598、GB/T 13927、JB/T 9092|
|Pressure temperature rating||API 598、GB/T 13927、GB/T 26480、JB/T9092、JB/T3595|
1, the valve cavity using pressure tight sealing structure, good sealing performance.
2, the valve, valve seat sealing surface cobalt based carbide alloy surfacing, wear-resistant, high temperature, good scratch resistance, long service life.
3, The valve stem is treated by corrosion resistance and nitriding. It has good corrosion resistance and scratch resistance.
4, high temperature creep design.
5, the valve cover stuffing box depth reasonable, filler plus corrosion inhibitor, sealed reliable.
6, the valve has an upper sealing structure, to ensure that the valve opens when running, the valve stem will not leak.
7, the valve drive mode manual, gear drive, electric, remote control and automation requirements can be achieved.
The utility model relates to a gate valve of a power station (main steam gate valve), which is suitable for pipelines of hot water, steam, oil, and superheated steam at a high temperature and a high temperature, such as a power plant, an oil chemical industry, metallurgy, etc..