Studying of speed on the process drill string flattening vertical wells

Abstract

The issue of vertical wells curvature is important, especially when conducting wells in complex geological conditions of drilling, due to the increasing depth of the wells and the corresponding rise in the cost of drilling. The cause of this circumstance lies in the large time and financial costs while flattening of the bent wells. Moreover, it should be noted that during the subsequent drilling of a curved well the risk of key-seating and the corresponding complications increases. That is why large oil field service companies and drilling enterprises are paying more and more attention to solving the problem of vertical wells curvature.
This article is devoted to investigation the effect of rotation of the drill string on the deflecting force on the bit while drilling a vertical well in a rotary way. We suggest using of eccentric drill collars for drilling vertical wells in difficult geological conditions. Also, we create an expression for the dynamic milling force on the bit, taking into account the usage of an eccentric drill collar in the composition of bottom-hole assembly.