Improvement of longwall operation using real-time shield pressure monitoring

Longwall mining achieves higher productivity with better safety records and provides opportunity for full automation. Today, the use of wide longwall face and its fast advancing rate can achieve an ever more production. However, this technique can create unexpected hazardous conditions such as face failures, excessive face convergence, shield damage and numerous maintenance problems, which may interrupt coal production. To evaluate these problems in real-time, shield legs are equipped with electronic pressure sensors for monitoring pressure from underground to the surface. These data provide information regarding face conditions such as shield yielding, periodic weighting, shield maintenance problems, shearer location, etc. A longwall Strata Control and Maintenance System (LoSCoMS) was developed at The University of Alabama, USA to analyze pressure data in real-time and forecast forthcoming periodic weighting and shield pressures. This system is also being used everyday to reduce out-of-seam material cutting and improve productivity.