During drilling, how to drill a wellbore vertically is a common technique issue. Though there are some anti-deviation and well straightening methods at present in drilling fields, most of them have their disadvantages, such as decreasing the weight on bit (WOB) and the rate of penetration (ROP). These drilling methods can't achieve the aim of deviation control and fast drilling economically and effectively in high dip, fractured, fault zones, and other abnormal formations.
Automatic Vertical Drilling System (AVDS) is a Mechanical-Electrical-Hydraulic integrated drilling tool, and it is also an intelligent drilling system. As an advanced technology, the AVDS is a great breakthrough in deviation control and fast drilling. According to the result of theoretical analysis and oilfield applications, the AVDS can not only increase the weight on bit and improve the rate of penetration greatly, but also can guarantee improved well bore quality. And perfect borehole quality is an important premise of subsequent operation while drilling.
By the results of the experiments, the indexes of the AVDS have met the design requirements and achieved vertical and fast drilling aim in high dip formations. The paper aims to introduce the characteristics, operating principles and matching technologies of the AVDS.