supply of hexagonal drill rods size 22mm x 1800mm with 6mm central hole and with water manifold , hexagonal drill rods size 22mm x 1800mm with 6mm central hole and with water manifold . technical specification:- scope :- a ) use of drill rod : in coal mines . b ) the rods shall be manufactured from solid hexagonal type section . c ) material: - the drill rods shall be manufactured from high tensile steel special steel of grade 55 simncrnimo with surface hardness 50-55 hrc . d ) the length of drill rod as measured excluding water manifold & shank for drill chuck shall be 1800mm . e ) diameter of hexagonal rods shall be 22mm with central hole of 6mm . f ) diameter of shank shall be 19mm & length 70mm . g ) accommodation of drill bit:- m-16 thread shall be provided at the end to accommodate 27mm diameter drill bits with threaded end . h ) adopter of 39 . 7mm diameter x 22mm long shall be provided for holding the rod in drill chuck of 25mm square x 22mm long adapter . i ) drill rods shall be suitably electroplated to provide a surface hardness of 65-86 hrc . j ) hexagonal drill rods for resin capsule bolting shall be supplied with water manifold as below:- i ) water manifolds shall be made from high grade seamless tubes . ii ) water pressure of water outlet from drill rods shall be minimum of 30 kg/m2 . iii ) high quality bearings and oil seals shall be provided in the manifold so that there shall not be any water leakage from water manifold during drilling operation . k ) each rod shall be marked on the shank with the diameter of the rod and manufacturers name , make/trade mark .