DOUBLE-ACTING HYDRAULIC DRILL JAR Russian patent published in 2020 - IPC E21B31/113 

FIELD: oil, gas and coke-chemical industries.

SUBSTANCE: invention relates to oil and gas industry, in particular, to equipment for well drilling. Proposed device comprises tubular housing with hollow shaft telescopically arranged therein to move freely in case axial direction. Shaft and housing are made of connected parts and housing part are connected by housing adapters. In the body the first and the second pistons are installed, between them the chamber filled with working fluid between the body and shaft is formed. Between housing and shaft there is a cavity with which throttles oppositely directed in axial direction of jar, interconnected with said chamber, are interconnected. Jar is equipped with enveloping shaft common for throttles annular housing, in which there is a pair of diametrically located threaded holes with located in them counter-directed in axial direction throttles. Annular housing is located between ends of housing adapters with possibility of their inner surface interaction with shaft bulge during its movement between end faces of adapters, as well as possibility of its end faces interaction with end faces of housing adapters. In wall of annular housing on its opposite end sides there are inclined holes communicated with threaded holes communicated with cavity formed by housing, shaft and ends of adapters.

EFFECT: simplified design, increased reliability of operation.

1 cl, 5 dwg