دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a type of mechanical jar in which a fluid moving through a small opening slows the piston stroke while the crew stretches the work string. After the hydraulic delay, a release mechanism in the jar trips to allow a mandrel to spring up and deliver a sharp blow. Compare mechanical jar, rotary jar.

n: a tool that is shocking while drilling ,its mainly used to jam release.

n: the length of movement, in inches (millimetres),of the piston of an engine from top dead centre (TDC) to bottom dead centre (BOC).