Doubts about the gasket coefficient m
Thread Content
The gasket coefficient is given by the formula m = p/p1, where P represents the effective compressive force on the gasket (the preload minus the operating pressure of the piping system), and P1 represents the operating pressure of the piping system. This value of m is often referred to as the gasket coefficient or the residual specific pressure coefficient. Different gaskets have different values of m, and this value increases as the hardness of the gasket increases. Both the gasket coefficient m value and the preloading pressure ratio y value are values specific to the gasket itself, and their values vary depending on factors such as the gasket’s shape and material. -----Boundary line—— I have a question: why not simply use the effective compressive force of the P---gasket (preload minus the operating pressure of the piping system) to determine the amount of preload that needs to be applied, instead of requiring that the effective preload P must be m times the operating pressure P1 of the piping system?
The actual required pre-tensioning force is = (m+1)P
Thank you. What is the relationship between the pressure that causes the gasket to deform and thus achieve sealing, and the internal pressure of the piping system? It has to do with the material of the gasket. I think the minimum preload required actually equals the specific pressure y required by the gasket itself plus the internal pressure P in the piping system. Is my reasoning correct?
It is the residual sealing pressure that enables the gasket to provide sealing, while it is the preload that causes the gasket to deform in order to achieve sealing. The greater the pressure that needs to be sealed, the higher the m-value of the gasket that should be used, and the greater the preload required as well.