Real time analysis for forecasting of chock shields performance a case study

摘要

Difficult caving characteristics of overlying strata have been experienced in most of the Indian longwall faces. Caving of the roof is very important aspect for successful longwall operations. The increase in uncaved roof span will cause dynamic loading on the chock shields and face due to sudden increase of leg closure and pressure. In most of the cases conventional yield valves do not respond to dynamic loading, because of the design constraints. Further, goaf overhang will increase the front abutment stresses and initiate the severe face spalling. The severe face spalling will deteriorates the safety and productivity of the longwall faces. In addition, the efficiency of the chock shields is reducing for every panel extraction due to complex geomechanical conditions. The efficiency deterioration is leading to hydraulic leakages. The increased hydraulic leakages, which are continuously overloading the power pack pump resulting in frequent failure. The deteriorated condition of hydraulic systems, chock shields are not offering adequate resistance. Thus the strata control problems are enhanced. This complex situation was disturbed face operations very often. Therefore, the continuous monitoring and analysis of chock shields performance is imperative for forecasting in real time for improving productivity and safety of longwall operations. This paper discuss the analysis and forecasting of the chock shields behavior in real time. The authors successfully developed the Real Time system with state-of-the-art-technology. This innovative system was successfully implemented in one of the Indian problematic longwall mines for continuous monitoring, analysis and forecasting of chock shields behavior. Therefore, the Real Time system has improved safety and productivity of longwall operations. However, this paper will mainly concentrate discussions on analysis and forecasting of chock shields behavior.