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Drilling principle of hydraulic anchor drilling machine
writer:ld-driller | time：2020-09-03 16:04:15

Hydraulic anchor drilling machine drilling adopts rotary drilling machine hydraulic drilling method to form holes. Before drilling, the design, supervision, geology and construction units should arrange holes according to the geological conditions on site, and pay attention to the following aspects when drilling:

(1) after the drilling rig is in place, the vertical, horizontal and angular deviation of the hole position should be corrected according to the design requirements, and it should be perpendicular to the retaining wall.

(2) the hole wall should be straight so as to place pull rod and grouting.

(3) in order to maximize the anchoring effect of the anchoring section, the hole wall shall not collapse or loosen, otherwise it will affect the placement of the pull rod and the bearing capacity of cable anchor.

(4) when drilling, it is forbidden to use the circulating slurry supporting of bentonite to avoid forming Peel on the hole wall and reducing the bearing capacity.

(5) allowable deviation of drilling: horizontal deviation 50mm, vertical deviation 20mm, angle deviation 0.5 degrees.

When the drilling anchor section is anchor drilling machine, replace the hydraulic reaming drill bit, and expand the aperture by using the water injection pressure.