摘要 |
FIELD: construction.SUBSTANCE: invention relates to helical earthmovers and may be used in construction, geological prospecting and in households. An underground drilling assembly comprises a drive and a helical earthmoving element - a replaceable drilling attachment. The helical earthmoving element is made in the form of a regular trihedral pyramid comprising a cutting part at the pyramid top and a propelling agent having blades on pyramid ribs rounded with a radius R=R-H/2 along a triple-stage helical line, besides, the cutting part starts in the points R=0, where R - radius on ribs of the regular trihedral pyramid; R- the radius of the circumscribed circumference of the regular trihedral pyramid; H - distance between the axis of the regular trihedral pyramid and centres of radii on rounded ribs of the pyramid.EFFECT: invention provides for well drilling in an autonomous mode at large depth and in any plane without soil removal.1 dwg |