Table 11.7
Conversion factor
b of impact frequency of impactor
J Series
W-210
DHD Series
DHD-260
100
150
170
200
275
325
400
500
24
15
15
16
Air pressure
(MPa)
0.5
0.62
0.62
0.56
0.69
0.54
–
–
–
–
–
–
–
–
–
0.7
–
–
–
–
–
0.38
0.40
0.39
0.40
0.52
0.49
0.52
0.53
0.52
1.76
–
–
–
–
–
–
–
–
–
–
–
–
–
0.35
Valve distribution
type
Plate valve
Valveless
Butterfly valve
Valveless
214
11 Pneumatic Down-the-Hole Hammer