WELL PLUGGING DEVICE Russian patent published in 1995 - IPC

FIELD: well drilling. SUBSTANCE: well plugging device has container 1 with piston 3 which separates container into above-piston space 4 and working space 5 filled with grouting material, and pulser. Pulser has body 8 with axial channel and discharge ports 9, upper adapter 10 with inlet channel 11, lower adapter 12, supply nozzle 13 and receiving nozzle 14 and disk deflector 15. Adapter 10 is installed for rotation relative to body 8. Connected with body 8 and container 1 is lower adapter 4. Nozzle 13 has holder 17 installed in body 8 and is hydraulically communicated with channel 11. Nozzle 14 is installed in lower adapter 12 and hydraulically communicated with lower adapter 4. Deflector 15 is located between nozzles 13 and 14 and rigidly connected with adapter 10. Holder 17 is secured by means of central connector 18 relative to lower adapter 12. Holder 17 and lower adapter 12 have through bypass channel 31 hydraulically communicated with channel 11. Lower adapter 12 has cylindrical axial projection 27 on the side of lower adapter 12. Projection 17 has radial holes 30 hydraulically communicated with channel 31. Device has member signalling on ending of working stroke of piston 3 made in form of sleeve 28 installed on projection 27 for overlapping holes 30 and spring- loaded relative to lower adapter 12. Sleeve 28 is connected by means of flexible link with piston 3. Device is lowered into well, drill string is rotated and mud pump is started. Pulser forms pulse pressure which is transmitted to piston 3 and material forces it out. At the end of stroke piston 3 through link moves sleeve 28. Holes 30 open and drilling mud enters lower adapter 4 and further moves towards flow from nozzle 14. EFFECT: higher reliability and longer service life. 1 dwg