DTH Drill Rods (Tubes/Pipes) and Sub Adaptors: Acedrills has DTH drill rods with several different thickness designs for each diameter, made from different grade steels for selection. So, in practice of field drilling, under different condition, there may be in need of different kinds of drill rods for particular application. For example, the thicker ones with general high quality grade steel for drilling hole of average depth, such as blasting holes; and the thinner ones with better grade steel for drilling hole of very deep, such as drilling for ground thermal. Moreover, Acedrills DTH drill rods are also well heat-treated, precision manufactured, and friction-welded.