Working principle and characteristics of high pressure stop valve

Working principle and characteristics of high pressure stop valve

What is a high pressure stop valve? The opening and closing part of the high pressure stop valve is a plug disc, the sealing surface is flat or conical, and the disc moves in a straight line along the center line of the fluid. There are two types of stem movement: one is the lifting rod type (the stem moves up and down without the handwheel rising) and the lifting rotary rod type (the handwheel is set on the body with the stem rotating rise and nut). Globe valve is only applicable to full open and full closed, do not allow adjustment or throttling. So what is the purpose of the globe valve?

First, the working principle of high pressure stop valve

High pressure Angle globe valve is a forced seal valve, so close the valve must apply pressure to the disc, to prevent the sealing surface leakage. When medium enters the valve from below the disc, the resistance that must be overcome is the friction between the stem and the packing and the thrust generated by the medium pressure. The force to close the valve is greater than the force to open it, so you need to increase the diameter of the stem. Otherwise, the stem will bend and fail. In recent years, with the emergence of self-sealing valves, the flow direction of the medium of the globe valve has been changed from the direction of the valve seam to the direction above the valve chamber. Due to the large size, the diameter can be reduced accordingly. At the same time, under the action of the medium, such valves also become tighter. When the high pressure globe valve is opened, the opening height of the disc is 25% ~ 30% of the nominal diameter, and the flow rate reaches a certain degree, indicating that the valve is in the fully open position. Therefore, the full open position of the globe valve must be determined by the stroke of the disc.

Two, the characteristics of high pressure stop valve

High pressure stop valve has the following advantages:

1, simple structure, more convenient manufacturing and maintenance;

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

3. Excellent sealing performance, small friction sealing surface, long sealing time.