Abstract: There are many advantages for coal tar enamel in corrosion protection. However, the key technique of such corrosion protecting material is the dipping divice for coal tar enamel external wrapping tape and joint coating tape of pipeline. The paper makes a conclusion on such technique and device and emphasically introduces the structure and the working principle of such dipping device for external wrapping tape and joint coating tape, as well as those calculations for the power of various parts and the speed of traction, etc.