supply of drill rod hexagonal 22 mm ( as per enclosed drawing ) , drill rod hexagonal type for resin capsule bolting with 6 mm centre hole without water manifold: size of drill rod ( diameter ) : 22 mm , length of drill rod : 2100 mm . technical specification:- ( i ) scope : use of drill rod: in coal mines , ( ii ) the rods shall be manufactured from hexagonal type section , ( iii ) material - the drill rods shall be manufactured from high tensile steel special steel of grade min 0 . 55% carbon with surface hardness 50-55 hrc , ( iv ) the length of drill rod as measured excluding square drive & shank for drill chuck shall be 2100 mm , ( v ) diameter of hexagonal rods shall be 22 mm with central hole of 6mm . ( vi ) diameter of shank shall be 19 mm & length 70 mm . ( vii ) accommodation of drill bit - m-16 thread shall be provided at the end to accommodate 27mm diameter drill bits with threaded end , ( viii ) square drive adopter of 25 mm x 22 mm long shall be provided for holding the rod in drill chuck , ( ix ) each rod shall be marked on the shank with the diameter of the rod and manufacturers name , make/ trade mark . ( dimensions will be as per enclosed drawing )