DP-920GH thermal friction drill is the high speed version of DP-920G. It’s also called high speed sheet metal tapping drill. This kind of drill is used in any application where the material has thinner thickness such as sheet metal or pipe. It does not have enough support for a threaded surface or a sleeve bearing application. The high rpm up to 4000 generates heat to make the material soft. As the bit contacts the material, it’s easily pushed through the material. Some of the melted material is being pushed and formed a collar around the upper surface of the work piece. The rest of the material is being pushed down and formed a bushing in the lower surface of the work piece. The entire tapping is done in few seconds. The resulting collar and bushing can be up to 3 times to the original material thickness. The diameter of the bushing depends on the size of the drill bit. The pushing process does not destroy or damage the inner structure of the material but as a result form a very strong bushing, which can be used for threading and bearing sleeves.