WELL TUBING CUTTER-MILL Russian patent published in 2013 - IPC E21B29/00 

FIELD: mining.

SUBSTANCE: device comprises a body 1 with a stepped bore 10, where a perforated orifice 11 is installed with longitudinal holes 12, resting on the nut 12, installed on the upper end of a stem 4, under which there is a spring-loaded piston 3. In the axial channel of the orifice 11 there is a nozzle 14 with a collet 15 on the lower end, tabs of which are introduced into the axial channel 18 of the nozzle. As the tabs are pressed, a seat 16 is formed for a ball 17. In longitudinal slots of the body there are cutter holders 6 reinforced with a hard alloy and installed on axes 7. The stem is equipped with an extender 19 with a circular piston 20, forming a movable joint with the body, on the outer side of which there is a limiting bushing 22, pressed with the adapter 21. In the axial channel 23 there is a control bushing 24 with a seat 25, on which a detachable valve is installed, comprising a sleeve 30 with a collet 31, inside of which there is a fixator inserted in the form of a bushing 32 with a mount seat 33 for a ball 17. In the axial channel of the adapter there is a throttling orifice 26 with a case 28 and relief holes 27.

EFFECT: expanded process capabilities of control over cutting process, optimised liquid flow rate.

3 dwg