HYDRAULIC DOWNHOLE ENGINE Russian patent published in 2009 - IPC E21B4/02 

FIELD: engineering industry.

SUBSTANCE: invention refers to hydraulic drives used for rotary drilling and located in wells, and namely to fishing devices meant for lifting fallen shafts of spindles with a bit, and can be used in hydraulic gerotor-type screw engines and turbodrills for drilling inclined and horizontal oil and gas wells. Hydraulic downhole engine consists of a housing with a rotor located thereinside, and the rotation of which is performed by the pump feeding of fluid medium, and housing of spindle with a shaft located thereinside and installed on radial thrust bearings and also on upper and lower radial sliding supports; spindle shaft is connected with a drive shaft to rotor and attached to the bit; housings of engine and spindle are fixed with a threaded sub; lower radial support of spindle is located in threaded nipple, and nut connected to threaded nipple is provided with a fishing belt. Spindle shaft is provided with threaded belt located between lower radial sliding support and outlet shaft part meant for fixing the bit; on threaded belt of spindle shaft there fixed is a threaded bushing whereon there made is a fishing collar intended for interaction with fishing belt of nut connected to threaded nipple. Diametre of fishing collar of threaded bushing does not exceed diametre of outlet spindle shaft part.

EFFECT: increasing life time and reliability of engine spindle, reducing accident risk when lifting downhole engine with a drilling string out of inclined and horizontal wells, improving accuracy of well making and rate of set of parametres of well curvature, improving passing ability, ie reducing resistances and stresses in the layout of drill column bottom, as well as providing use of bit of one and the same diametre of two adjacent sizes of layout of drill column bottom.

3 cl, 3 dwg