Design Notice Of Guide Hole - XCMG XZ320 Operation Instructions Manual

Manual of XZ320 Horizontal Directional Drill
bending angle of single auger stem or it may be damaged.)
Attention：Stop operation and find out reasons instantly if
single auger stem has larger angle variation within shorter
distance. Auger stem, drill bit, beginning rod, pivot plate even
probe rod may be damaged if continuing to operate the machine.
Do not push the power head forcefully if it is difficult to change
pushing direction of auger stem to avoid bending. Auger stem can be
close to steering direction for slow rotation and pushing within scope
of 45° sector.

5 Design notice of guide hole

Guide holes shall be designed to evade underground pipelines and remain
sufficient safety distance. Measured depth of underground pipes deviates
from actual depth and detected and measured values are different
especially under large disturbance. Therefore, sufficient safety distance
shall be remained when designing the guide hole. In general, safety
distance shall be 1m during actual construction and it must reach 0.5m.
Guide hole below the water level shall be designed to horizontal hole as
practicable as possible when passing across the river. In general, guide
hole shall be at least 3m away from bottom of river bed because pipes may
float due to super-small distance. In the meanwhile, guide hole is difficult to
construct due to small distance of river bottom and complex soil quality.
Guide hole shall be at least 4m away from road base when passing across
railway or highway. Depth shall be increased if expanding diameter is
larger. Various conditions on the site shall be collected completely when
passing railway and highway to guarantee safety of guide operators.
In general, depth of guide hole shall be not lower than 5m when setting
pipes below floors. Depth of guide hole shall be increased if expanding
diameter is large with soft stratum.
Points shall be set when passing across routes for construction site with
poor vision to control guide precision and define soil exit hole positions.
Auger stems of every factory have different bending radius and they may
be invalid due to early rupture even major loss if actual bending radius
exceeds permissible bending radius.
Be in accordance with three requirements at the same time when
designing the guide hole. That is, it is required to meet owner's
requirements and construction process and evade underground hidden
articles. Coordinate with entrusting party to check if construction route can
be changed or not if construction location can not meet above conditions at
the same time. Project of which route can not be changed is preferred to
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