The article describes the dynamics of drill bits, drilling modes, distribution of resistance forces when drilling with bits. The theory of drilling a well of arbitrary shape, possible shapes of contacting figures at the bottom hole and the type of drill bit operating in the rotation pair mode are considered. This type of bit has the properties of a double center of rotation, which results in attrition drilling. At the same time, during drilling, the load on the bit will be located the same throughout the working part, it is also theoretically shown that the specific volumetric and contact work of the cutting parts will be the same, which leads to the same wear of the bit. It also discusses the issues of improving the flushing and blowing of wells when drilling with rotary steam bits.