The hydro mechanical steel cogs for underground mining applications have been designed by The Central Mining Research Institute at Dhanbad. Necessity for such design arose as wood which are being used for conventional supporting in the past have already become scarce causing a great concern among mines safety officials who used wooden props earlier. Further wooden supports do not have the provision for pre-setting loads while installation, the Hydro Mechanical Steel Cogs which are available in two models .Viz; 20T & 40T capacity obviate such short comings and are designed to provide. Goaf edge supports in depillaring areas in underground mines and for supporting of development areas particularly injunctions, slices. The Hydro Mechanical Steel Cogs are so fabricated as to facilitate easy assembly and are therefore constructed in three parts viz; the base frame, the central cylindrical portion for height adjustment and the top supporting canopy frame.
