The Strength of Valves at Closing

THE speed at which a valve is coming to rest on its scat at the moment of closing is one of the factors deciding the amount of gases passed through the valve. The inertia forces, however, act for a very short time on the valve at this moment, and this is the reason why normal considerations in the strength of valves are not accurate; it would be better, when designing the valve, to use approximate calculations giving the possibility of orientation among the various factors coming into consideration, than to leave all this to experimental practice.