User's Manual

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RIOTRONIC X+
User Manual
9.2.5.1. The method of signature hole
Figure 117. Analysis using MAXAM software
Figure 118. Relationship between PPV, delay time and frequency
Based on analysis of the signature hole, the minimum PPV and maximum Frequency is
generated by an inter-hole interval of close to 25ms (Figure 118). The inter row timing should
be chosen trying to avoid overlapping with holes located on the previous line.
9.3. Blast Design Parameters
Initiation is not everything and the electronic detonator will not solve all problems. The
drilling and explosive parameters must also be properly controlled to achieve the best
results.
The main variables that a blast designer must consider are as follows:
 Blast-hole diameter
 Excavation depth (bench height)
 Angled blast-holes
 Burden and spacing
 Blast-hole pattern
 Subdrilling
 Explosives distribution