دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: an eccentrically shaped disk, mounted on a camshaft, that varies in distance from its centre to various points on its circumference. As the camshaft is rotated, a set amount of motion is imparted to a follower riding on the surface of the cam. In the intenal-combustion engine, cams are used to operate the intake and exhaust valves.

n: the cam-operated mechanism through which burned gases are ejected from an engine cylinder.

n: a device that controls the rate of flow of fluid in a line or opens or shuts off the flow of fluid completely. When open, the sealing surface of the valve is moved away from a seat;when closed, the sealing surface contacts the seat to shut off flow. The direction of movement of the valve is usually perpendicular to the seat. Poppet valves are used extensively as pneumatic (air) controls on drilling rigs and as intake and exhaust valves in most intemalcombustion engines.

a type of valve common on early subsurface safety valves, where higher than expected flow through an orifice can move a round ball onto a sealing surface and stops the flow.

n: a set of gears in an engine, driven by the crankshaft, set to drive the equipment necessary for the engines operation. Engine equipment driven by the timing gears includes the oil pump, intake and exhaust valve mechanisms, fuel injectors, and magnetos.