Table 11.12
Performance parameters of DTH hammer impactor under different intake pressure
Intake
pressure
(MPa)
Maximum return
displacement (m)
Maximum
return speed
(m/s)
Maximum
stroke speed
(m/s)
Impact bit
speed (m/s)
Maximum return
acceleration (m/s
2
)
Stroke maximum
acceleration (m/s
2
)
Impact
work of
piston
Impact
frequency
1.4
0.164
5.67
7.55
7.07
292.16
225.86
5748.3
10.93
1.1
0.158
4.94
6.47
5.97
224.68
173.46
4098.7
9.79
0.8
0.150
4.08
5.23
4.74
190
122
2583.8
8.47
11.4 Dynamic Process and Theoretical Model of Large Diameter …
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