US Patent 11313194 Retrieving a stuck downhole component

A wellbore assembly including a cable disposed within a wellbore and a fishing jar assembly coupled to the cable. The fishing jar assembly includes a housing assembly, a mandrel assembly, a fishing assembly, and an actuator. The housing assembly has an inwardly projecting shoulder defining an anvil surface and a hydraulic fluid chamber housing hydraulic fluid. The mandrel is movable along a central axis of the housing assembly and has an outwardly projecting shoulder that defines a hammering surface to strike the anvil surface. The mandrel assembly defines a piston disposed within the hydraulic fluid chamber. The fishing assembly engages a component stuck within the wellbore. The actuator moves the piston of the mandrel assembly along the longitudinal axis to pressurize the hydraulic fluid until the hydraulic fluid bleeds past a fluid port allowing the mandrel assembly to trip to strike the anvil surface with the hammering surface.