Question regarding the effective perimeter in the definition of Ag for the calculation of the minimum cross-sectional area of the valve body and valve cover connection studs
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This post was last edited by Zhou Liuliuxu on 2019-11-28 at 18:16. In the standard GB/T 12237-2007 \"Steel ball valves for use in the petroleum, petrochemical, and related industries\", section 5.6.6 specifies that the minimum cross-sectional area of the bolts or threads used to connect the valve body to the left valve component, as well as between the valve body and the valve cover, must comply with the corresponding calculation formula. In the formula, Ab is defined as the area bounded by the effective outer perimeter of the gasket or O-ring, or by the effective perimeter of its sealing element; except in the case of the gasket ring contact surface, where this bounded area is determined by the inner diameter of the ring, and is expressed in square millimeters (mm2). May I ask whether the effective outer perimeter of a gasket or O-ring refers to its inner diameter or outer diameter? I noticed that in the calculation sheets, the inner diameter of the gasket is used as the effective outer perimeter for calculations; I’m not sure whether it refers to the inner diameter or the outer diameter. Also, is Ab equal to (π*dM^2)*Z/4, where dM is the diameter of the stud and Z is the number of studs? Please help me understand this, experts
The effective sealing surface area of a gasket usually refers to the area of the circular cross-section of the gasket.
Original poster, have you understood the meaning of that sentence above? Could you explain it to me?:hug:
It is the circular area defined by the average diameter of the sealing surface, that is: Ag=π/4*（dmp^2).
What does DMP mean? For a gasket with dimensions Φ120*Φ100, should the diameter of Φ110 be used to calculate the area? Is π*55*55=9503.318 correct? {:1_90:]
120×100 circular gasket, average diameter dmp=110, area=π/4*110*110