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One of the most important properties of an explosive is its velocity of detonation (VOD). It is essential that the explosive should detonate at its optimum rate and release sufficient detonation pressure to get good fragmentation under the existing field conditions. The main objectives of this research study are to investigate the effects of explosive type, blast hole diameter, and degree of confinement on the VOD of bulk ANFO and bulk emulsion in Kumtor Open Pit Gold Mine. In this study, the continuous resistance wire method is employed to measure in-situ VOD of both bulk ANFO and bulk emulsion. The VOD values are measured for different hole diameters and under different confinements for both explosives. The ideality of bulk ANFO and bulk emulsion is calculated by comparing the in-situ measured VOD&rsquo / s and their ideal detonation values. It is found that the VOD of both explosives increases as the blast hole diameter and the degree of confinement increases. In addition to this, VOD of bulk ANFO decreases when it gets wet in the blast hole. Another finding is that, proportion of bulk emulsion ingredients has influence on its VOD. This research study provides a good understanding to use suitable explosive in existing rock conditions in Kumtor Open Pit Gold Mine.

The increase of intelligent systems can be seen in every industry. Integrated sensors and processors are used with internal control systems to create better performance for mobile hydraulic applications. The report describes how an evaluation was made to see if the productivity of a drill rig could be increased. This was done by implementing a programmable hydraulic valve to control the hydraulic drilling functions. The productivity would be increased by reducing the downtime due to jamming in the drill hole. Jamming occur when the system does not compensate for changes in rock conditions. By conducting a series of tests in a controlled environment with simulated loads, the response time of the CMA system and original system could be determined and compared. The CMA system had a response time that was 60-64% faster than the original system. Two different implementations of a controller was tested. Ziegler-Nichols method was used to get the initial value of the PI parameters. The controller that was implemented onboard the valve’s CPU was considered more successfull to reduce jamming. A drill test was conducted to ensure that the programmable valve could handle a drilling procedure with the controller that was implemented onboard the valve’s CPU. The valve handled the drilling procedure well.