Study on compound drilling technology of turbodrill

The compound drilling technology of the turbodrill is one of the main methods to increase the penetration rate and realize the deviation control and fast drilling.In pace with the perfection of performance and model number of turbodrills,as well as the rapid development of high efficiency of PDC bits,the compound drilling technology of turbodrill will be widely used.Based on comparing the structure,performances,advantages and disadvantages of the turbodrill and screwdrill,the concept of the optimal conditions for compound drilling of turbodrill is proposed,as well as the speed range is shown clearly.The compound drilling mechanism of turbodrill is elaborated in detail after analyzing the characteristics of turbodrill and coordination requirements for PDC bits.What’s more,a dynamic and longitudinal vibration model of the turbodrill system used in the drilling process is established,which lays the theoretical basis for obtaining the best results of compound drilling of turbodrill.The deviation control and fast drilling has been shown in the typical region of high-steep structure in China.As a result,the drilling speed is obviously improved,the drilling period is shortened,the cost is reduced considerably,and remarkable economic results are obtained.