improve blast performance with borehole surveys

Do you want to decrease the potential for fly rock or unintended rock movement during blasting? Are you interested in improving blast fragmentation? Would decreasing the variability in floor elevations help your site?

All these concerns can be addressed through accurate borehole drilling and verification of the actual design compared to the initial design. Consider this: you design a pattern, you drill it, you blast it; but because things do not always perform as planned, you still notice issues with the blast performance. What is causing this? Do these issues indicate that the design is not working, or is there another cause? An easy solution for addressing concerns and determining the root cause related to blast performance issues is through a simple audit to ensure blast patterns are drilled within the tolerances of their design. Boreholes drilled incorrectly can lead to serious consequences in safety and production. Larger material can cause crushing systems to work harder. Flyrock and unintended rock movement can damage nearby structures or equipment. Uneven floors can cause additional work for bench preparation and impact the quality and performance of subsequent blasts. All these consequences have the potential to indirectly lead to an increase in the overall operating costs, which can be minor in some cases but are often more than you might think.

When optimizing a blast, the RESPEC team recommends and performs borehole surveys to confirm the blast pattern is drilled according to the initial design. As the U.S. distributor for all Carlson LMD equipment, our team uses the Carlson Boretrak2 borehole survey tool to understand the borehole deviation and orientation. This tool incorporates an internal gyro compass to take directional measurements throughout a borehole. The initial azimuth of the Boretrak2 when it is calibrated is all that is required for deployment, which can be in any direction—downhole, uphole, horizontally, or 360 degrees. As the tool is deployed, readings are taken at incremental measurements through the borehole, creating a survey string