DOWNHOLE FISHING TOOL Russian patent published in 2006 - IPC E21B31/08 

FIELD: mining, particularly for fishing or freeing objects at well bottom.

SUBSTANCE: fishing tool comprises body with pulling member, auger with shank arranged in body interior and spring-loaded in axial direction, as well as sludge trap and auger rotation drive made as non-locking screw pair. The pulling member is rope connected with auger shank so that rope may be rotated relative the auger. The body is made as inversed cup. The auger is provided with bearing assembly installed on shank between cup bottom and spring. The sludge trap is made as container with perforated bottom arranged below upper end of spiral auger blade.

EFFECT: reduced labor inputs and tripping operation time, simplified structure and increased operational efficiency.

2 cl, 1 dwg