Furnace tapping tools include rods, shank adapters, couplings and bits. They can be used with cross bits and button bits. There are mainly 2 types of rods:R38-Round39-R32 and T38-Round 39- T38. Blast Furnace Taphole Drill Rod a.38mm*12-14mm(1.496"*0.472") b.34mm*11mm(1.338"*0.433") c.34mm*12mm(1.338"*0.472") Blast Furnace Taphole Drill Rod We are the Blast Furnace Taphole Drill Rod manufacturer,it is our featured product,then we can supply you high quality,competitive price with best service. 1) Our featured size(Outer diameter*wall thickness) a.38mm*12mm(1.496"*0.472") b.34mm*11mm(1.338"*0.433") c.34mm*12mm(1.338"*0.472") d.32mm*10mm(1.259"*0.393") e.32mm*11mm(1.259"*0.433") f.40mm*12mm(1.574"*0.472") g.40mm*14mm(1.574"*0.551") 2) Application:It was widely used  in big steel mill for Deliver liquid steel specially from blast furnace. 3) Length:3--8 meters