... Odex bits,Hole opener,DTH bits,Down the hole bits,DTH hammer,Hammer,Rock drill,overburden bits, Eccentric Reamer System ... enough for the casing tube to slide down behind the drill bit assembly.2 When the required depth ... carefully, whereupon the reamer swings in, allowing the drill bit assembly to be pulled up through the ... tubes that are to be left in the drill hole should be sealed at the bottom of ...