Pressure self-tightening principle
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May I ask everyone, for high-pressure valves such as those with a rating of 1500LB and a pressure-self-sealing valve structure, what is the principle behind this?
The principle is to use the pressure in the valve chamber to push the rear valve seat, thereby compressing the packing around the valve stem as well as the seal ring between the rear valve seat and the valve body, in order to achieve sealing.
Supports the 2nd floor. . . . . . .
Confirm whether it is called pressure self-tightening or pressure self-sealing. The latter refers to a type of seal between the valve cover and the valve body, used in high-pressure gate valves, globe valves, and check valves
Pressure self-tightening bonnet sealing: The pressure self-tightening valve body seal (Pressure Seal Bonnet) is an efficient type of valve body seal widely used in gate valves, globe valves, and check valves that operate under high temperature and high pressure conditions. http://www.enertech-power.com/image/Tech-ValPressureSealA.jpghttp://www.enertech-power.com/image/Tech-ValPressureSeal1.jpghttp://www.enertech-power.com/image/Tech-ValPressureSealA1.jpg Local sectional view A – View http://www.enertech-power.com/image/Tech-ValPressureSealA2.jpg Figure 1: Pressure self-tightening valve body seal 1. Valve body ； Principle of pressure self-tightening valve cover sealing: 2. Wedge-shaped valve body seal ring ； The system pressure P acts vertically upward in the direction of the valve stem on the bottom surface of the valve cover. According to mechanical principles, P is broken down into a force P2 that acts perpendicular to the sealing ring of the wedge-shaped valve body, and a force P1 that acts perpendicular to the side surface of the wedge-shaped valve body, as shown in Figure 1, through the contact between the valve cover and the inclined surface on the inside of the sealing ring. 3. Valve cover compression flange ； 4. Metal valve cover sealing limit ring ； 5. Valve cover retainer ring ； 6. Valve cover ； 7. Valve cover fixing nut: The higher the system pressure P, the greater the squeezing force P1 between the sealing ring and the inner wall of the valve body, resulting in better sealing performance of the valve body. Theoretically, the smaller the angle of the wedge-shaped cross-section, the higher the efficiency with which system pressure is converted into radial sealing force. In fact, if the angle of the wedge-shaped seal ring is between 10° and 20°, the system pressure will cause the valve cover, the seal ring, and the valve body to stick together, making it almost impossible to disassemble them. http://www.enertech-power.com/image/Tech-ValPressureSeal45degree.jpg http://www.enertech-power.com/image/Tech-ValPressureSeal25degree.jpg Figure 3: Force decomposition diagram. Tests showed that the optimal angle is around 25° (see Figure 3).
Finally found it, learned something from it, thanks :）