... ,T45,T51 2.manufacture of series drill rod 3.professional technical team 4.ISO9001:2008 T45 extension drill rod :Our company can ... , tapered drill rods and integral drill rods, MF drill pipe.extension drill rod.mainly used for mining, coal cutting, tunneling, rock ... cutting in quarrying.T38 extension drill rod,length from 1220mm,1525mm,1830mm,3660mm to 6095mm ...