Use of three-cutter bit drills with oriented flushing assemblies at fields of the Central Priob'ye

During operation of the existing three-cutter bit hydromonitor bits (D) only the ring zone on the periphery of the face which comprises no more than 30% of the entire area is exposed to a jet effect. A design has been developed and tested for flushing assemblies which makes it possible to expose to the jet effect practically the entire area of the face, to intensify cleaning of the D outfitting, organize and regulate streams of drilling fluid in the near-face zone. This is achieved through the use of two elongated inclined attachments forming the jets directed within the D between the cutter bits at different angles to the axis D. The third attachment is left of vertical. Testing of the new flushing assembly on 25 wells of the Ust'Balykskiy, Pravdinskiy and Mamontovskiy fields indicated the high effectiveness of its use. Analysis of results of operation of D of the type 9 M-212.7 with these flushing assemblies indicated that in the interval 1720-2020 m represented by elastic rocks, clays and argillites, drilling on D increased by 25% with an increase in mechanical velocity. In the interval 20202300 m represented by sandy-argillaceous rocks of different hardness and plasticity, an equal increase of drilling on D and mechanical velocity by more than 30% was observed with a decrease in stability of the supports D by 3%. In the interval 2300-2700 m represented by solid rocks, with a decrease in the operating time of D on the face by 21%, there is an increase in drilling on D by 25% and mechanical velocity by 37%. This reduces the consumption of D by 2.