Field Test of Deep Cutting Double Arm Shearer

摘要

A field test was conducted to demonstrate the deep cutting principle in relation to the creation of airborne respirable dust when longwall mining with a double-ended, ranging drum shearer. The test was carried out on the 3 North Longwall at the Quarto No. 4 Mine in Clarington, Ohio. Continuous recordings of dust levels were made at midface and near the tailgate on 27 shifts during which time 81 mining cycles took place. Drum speed and number of picks per line were varied systematically over this period. At the midface position there was a strong association between drum speed and number of picks with the level of airborne respirable dust, drum speed had a much stronger effect than number of picks over the experimental range, since a halving of drum speed reduced dust levels by approximately 60 percent while removal of every other vane pick resulted in only a 20 percent reduction. At the tailgate position, however, neither effect was strongly apparent. A tendency for the slower drum speeds to be associated with reduced power consumption and higher haulage speeds (and therefore production rates) was also noted. It is recommended that longwall operators operate at the lowest available drum speed wherever possible.