| 摘要 |
Tubular drill executive body has tubular body with tail element and auger at the outer surface, section earth-destruction crown, to each its section displaced in layout skewed and two-facet cutters are included, and rake-off scraper, at that the central front cutter of the section - two-facet one - is placed with possibility of formation of central cut in the flat circular face, and the next two ones that in turn cut soil to the side of central cut are skewed, each with two cutting edges, vertical and horizontal ones, inclined to cutting direction by angle , horizontal edge separates soil from end surface of the pit (up), vertical separates soil to the side of central cut, and the cutters are arranged each with decrease of height with respect to previous by direction of motion by value of vertical drill feeding motion during time for covering distance between those.
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