Answer: The return seat pressure refers to the static pressure at the valve inlet when the medium pressure drops to a certain value after the safety valve reaches the discharge state, and the valve disc contacts the valve seat again, that is, when the opening height becomes zero. It is not good to have a return seat pressure that is too low or too high. Too low will cause the loss of medium and energy. Too high will not reach the discharge volume, causing the valve to jump frequently. The principle is to adjust the return seat pressure as high as possible while reaching the discharge volume to reduce the loss of medium and energy.
Adjustment method: The return seat pressure is adjusted by the adjustment ring. The adjustment principle is the gap principle. The smaller the gap, the greater the resistance during the spraying, the greater the force to support the valve core to drop, and the more difficult it is to return to the seat. On the contrary, the larger the gap, the easier it is for the valve core to fall back, and the higher the return seat pressure.
For a safety valve with only a lower adjustment ring, the return seat pressure decreases when the adjustment ring is adjusted upward, and the return seat pressure increases when the adjustment ring is adjusted downward; For a safety valve with upper and lower adjustment rings, the distance between the upper and lower adjustment rings decreases, the return seat pressure decreases, and the distance between the upper and lower adjustment rings increases, and the return seat pressure increases.
