DRILL & BLAST
High-precision guidance systems’ compensation of actual topography design
blast design. T is can then be virtually displayed to the operator on-board the equipment and an audible and visual alarm appear if the machine enters a predetermined warning zone. Most drill guidance systems transfer their as-drilled data back to a central server in real time. T is allows the recorded data to be further analysed, trends established and the ability to respond to real-time deviations to plans given. Firstly, the recorded data can be used to identify issues in the pattern that has not gone to plan. For example, holes that have not been drilled far enough and need to be re-drilled, or holes that have been over-drilled and require backfi lling. Using a high- precision guidance system correctly allows the operator to do this in real time, getting it right the fi rst time. Drilling operations then do not have to go back to address these issues after the pattern is completed.
Drill collar above design elevation target now 14m
T e recorded data can then be used to adjust the loading or charge design of the blast. Adjustments to the loading of specifi c holes, or the timing or initiation sequences may be required as a result of holes drilled to a diff erent depth or in a diff erent location. In the case of the Leica J2drill solution, as-drilled information is stored in a database on a central server that can be retrieved by third-party systems as data becomes available.
Optimised blasting Depending on the conditions of the hole (dry or wet) or the hardness of the ground, an appropriate explosive product will be selected to place into the holes. A diff erent product may be required for diff erent holes, or even down the same hole if hard bands exist in the strata. Technology contained in Leica J2drill can help here. Using measurement while drilling (MWD)
Drill collar at design elevation target now 11m
Actual Topography Design Elevation
Drill collar below design elevation target now 9m
Planned hole depth = 10m
Standoff
Planned hole depth = 11m
Planned hole depth = 12m
10
www.engineerlive.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52