valve lead

valve lead

valve leadclick for a larger image
The number of degrees of the crankshaft before the top or bottom center, at which the intake or exhaust valves open or close. For example, if the intake valve opens when the crankshaft is 25° before the piston reaches the top of the exhaust stroke, the intake valve lead is 25°. Early opening of the valve ensures that it is fully open at the beginning of the induction stroke and that there is no time lag between the piston moving down and the mixture flowing into the cylinder, as would other-wise occur as a result of the inertia of the mixture.
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Additionally, Eaton's new software tool offers a simple way to identify cartridge valve lead times and match valve pressures with specific system requirements for fast and efficient configuration.
Dual-key locks fitted to each valve lead the operator, valve by valve, through the correct sequence of operation until the key which governs the end closure is freed.
pressure drop across the valve leads to the selection of equal percentage valve characteristic for all two-way valves in variable flow hydronic systems.
Prompt diagnosis of valvular embolism is essential as thrombosis of mitral valve leads to occlusion of left main artery.
The lack of ducting and control valve leads to an overall cost and weight reduction.