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• Comparison of drilling speed
2. Comparison of Drilling Speed
Drilling speed varies considerably depending on the work conditions. Use the factory test results shown in
the figure below for comparison purposes only.
<Test conditions>
Direction
: Downward drilling
Pushing force : 98 N (10 kgf)
Test material : Concrete panel with compression strength of 2,352 N/cm
2
(240 kgf/cm
2
)
0
100
200
300
400
500
600
700
10
12
14
16
18
20
22
24
26
28
Drill Bit Dia. (mm)
Drilli
ng S
p
eed (mm/min)
HITACHI DH28PC
C
B
HITACHI DH30PC2
HITACHI DH25PB