Delay analysis of mechanised longwall faces

Australia is the largest exporter of hard coal. With the large opportunity for economic, social and political benefits from coal as a natural resource, longwalls are widely adopted by the Australian Coal Industry. By the end of 1995, there were 28 longwall operations in Australia. The percentage of longwall productions covering total raw underground coal production has rapidly been increasing since the introduction of the first longwall mining to Australia. Meanwhile, significant attention has been paid towards increasing longwall productivity. Even though longwall systems are designed to cut and produce coal at rates of more than 1000 tonnes per hour, recent statistics show that most operations of Australian longwalls fall far below this figure. In response to this problem, the reseai'ch objective of this thesis was to identify as to why current longwall operations are not reaching the designed output capacities and recommend the means of increasing production and productivity to the optimum goal.