What is a high-pressure shut-off valve? The opening and closing part of the high-pressure shut-off valve is a plug shaped disc, with a flat or conical sealing surface. The disc moves in a straight line along the fluid centerline. There are two types of valve stem movement: one is the lifting rod type (the valve stem moves up and down, and the handwheel does not rise) and the lifting rotating rod type (the handwheel is set on the valve body together with the valve stem to rotate and rise and the nut). Globe valves are only suitable for fully open and fully closed, and do not allow adjustment or throttling. So what is the function of a shut-off valve?

1、 Working principle of high-pressure shut-off valve

The high-pressure angle globe valve is a forced sealing valve, so when closing the valve, pressure must be applied to the valve disc to prevent leakage from the sealing surface. When the medium enters the valve from below the valve disc, the resistance that must be overcome is the frictional force between the valve stem and packing, and the thrust generated by the medium pressure. The force to close the valve is greater than the force to open it, so it is necessary to increase the diameter of the valve stem. Otherwise, the valve stem will bend and fail. In recent years, with the emergence of self sealing valves, the flow direction of the medium in the shut-off valve has shifted from above the valve slot to above the valve chamber. Due to its large size, the diameter can be correspondingly reduced. At the same time, under the action of the medium, this type of valve also becomes tighter. When the high-pressure shut-off valve is opened, the valve disc opening height is 25% to 30% of the nominal diameter, and the flow rate reaches a certain level, indicating that the valve is in the fully open position. Therefore, the fully open position of the shut-off valve must be determined by the stroke of the valve disc.

2、 Characteristics of High Pressure Stop Valves

High pressure shut-off valves have the following advantages:

1. Simple structure, more convenient for manufacturing and maintenance;

2. Small work schedule and short opening and closing time;

3. Excellent sealing performance, small friction sealing surface, and long sealing time for daily use.