SUNWARD SWDM40 - Drilling Tools; Common Drilling Tools and Application

SWDM40 OPERATION & MAINTENANCE MANUAL
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7.2 DRILLING TOOLS
7.2.1 Common Drilling Tools and Application
Type of Drill Bit
Features
Suitable layer
Cone single head single auger
bit
Cone teeth drill successively,
that reduce load greatly; Cone
auger pilot drilling prevent or
reduce the possibility of
inclined hole; big screw pitch
distance, strong capacity for
conveying soil slag, but
small intensity; low
performance
Gravel-cobble layer, gravelly
soil, especially for the layer
with much and big
gravel-cobble and a weathered
rock formation with joint
fissures
Cone double head dual auger
bit
During drilling, dual teeth
work simultaneously, thus high
efficiency and stable drilling;
Cone structure for good guide
performance; Small screw
pitch distance, conveying
channel for soil slag is small
but with high intensity, and
good performance in guiding
and carrying rock.
Suitable for drilling under big
pressure, used for intermediary
weathered sandstone and
slightly weathered bed rock,
and gravel ground with small
particle size
Type of Drill Bit
Features
Suitable layer
Small screw pitch in the front
part, high intensity; the screw
pitch is double in the rear part,
the conveying channel for
soil slag increase.
Suitable for all kinds of
bedrock, pebble layers with
medium size
Big screw pitch, large soil slag
conveying channel, but small
intensity, bucket teeth (V20,
25T, BZ80)
Suitable for frozen soil without
water, cohesive soil, sand
layer, gravel layer with partial
cementation difference
medium particle size