Equipments of Underground Coal Mining

In early days, development was carried out by hand working (i.e. digging with pick and shovel, usually assisted by the use of explosives to dislodge most of the coal. Roof support was by hand set timber props and bars. Rail tracks were extended to the face and coal was hand loaded into skips, mostly horse drawn at that time. Over the years mechanization was gradually introduced, including (not necessarily in order):

• Coal cutters which could cut a narrow channel into the coal ahead of the development face to provide a second free face for explosives to break the coal into
  
• Powered (compressed air) drills for drilling shotfiring holes, usually rotary/percussive
  
• Replacement of horses by locomotives (battery or diesel powered)
  
• Powered (electric) loaders to pick up the broken coal and load into skips
  
• Development of roof bolts and powered drilling equipment (hand held, compressed air operated).
  
• Rotary roof bolting
  
• Mobile roof bolting machines
  
• Replacement of coal transport in rail skips with conveyor belts, shuttle cars being used to bridge the gap between face and belt end (see coal transport section)
  

While all this development work was going on, continuous miners which were able to both cut and load coal were being developed. Other development unit equipment is dealt with in other sections of this document (coal haulage, ventilation amd strata control) and the rest of this section will deal briefly with continuous miners only (with some reference to roof bolting).