| Summary: | This thesis is part of the requirements for the degree of Master of Science in Applied Geosciences and Rock-mechanics. The purpose was to analyse the rock-breaking operations by the five different remote- controlled rock-breakers that are located at different shafts and levels in the Kiruna mine operated by LKAB. The result of this analysis was that a large amount of data considering the obstacles that the rock-breakers have to destroy came to LKAB’s knowledge. Data such as volumes and material, shapes and number of contributions and sizes of the obstacles were found. According to the gathered data approximately 65 obstacles covers the shaft- entrances each day and the rock-breakers need in average 152 minutes for their daily operations. Instead of having almost 90 percent of the boulders made of waste-rock, as was assumed, the data showed that almost half of the obstacles were made of ore. Data about the operations that the rock-breakers performed (such as different times and types of operations) and some data about the effect the rock-breakers have on the production-chain (accessibility of the rock- breakers, the affect on the production and yearly production-losses) were also discovered. One result was that the average time for the different types of rock-breaker operations became known. It takes in average 5 minutes for a rock-breaker to destroy a boulder, roughly 2 minutes to destroy a bridge and 1.1 minutes to clean up around the shaft-entrance. It also became known that the obstacles made of waste-rock took longer time to destroy than the ones made of ore: 58.5% against 34.8 % of the total time needed for operations. Another result was that the accessibility of the rock-breakers was 68.6% and that LKAB yearly looses almost 420’000 ton due to short production-breaks in the five shafts covered by this work. LKAB had before this study mostly had assumptions to work with and wanted to change that. The gathering of the data consisted of several different operators filling in report-sheets of paper that later ...
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