WELL CLEAN OUT TOOL

摘要

A well clean out tool installed in a drill string is operable to pump sand and debris from the well bore. A pump portion includes an elongate pump barrel having apertures extending through its side wall at the upper end which is attached at its bottom end to one or more the debris-receiving and trapping subs and enclosed at its upper end by a top cap having a hexagonal opening. A hexagonal pump mandrel extends through the top cap and is connected to the bottom of the drill string by a top sub having apertures through its side wall whereby the pump barrel may be rotated with the drill string. A swab assembly contained within the pump barrel and connected to the bottom end of the pump mandrel is reciprocated thereby. The swab assembly includes a cruciform swab bypass mandrel having longitudinal fluid bypass channels with stop shoulders at each end thereof. One or more swab cups having internal metal sleeves ride on the exterior of the bypass mandrel. On the down stroke, the swab bypass mandrel moves down relative to the swab cups to allow passage of fluid through the bypass channels and the apertures in the pump barrel and the valves in the lower subs close to capture sand and debris in the subs. On the up stroke, the bypass mandrel moves up and the lower swab cup closes off the bypass channels. As the swab assembly is raised relative to the pump barrel, the valves open allowing sand and debris to enter the lower subs and the fluids within the pump barrel are discharged are discharged through the pump barrel outlets.