Laboratory Scale Control of Drilling Parameters to Enhance Rate of Penetration and Reduce Drill String Vibration

Abstract

Abstract Drill string vibration and shock loads are known as destructive loads while drilling and are the reason for tool failure, lost time and reduction in rate of penetration. Vibrations of drill strings can be effected by bit and bottom hole assembly design, interaction of bit/formation and drilling parameters. To manage vibration, however, weight on bit and rotary speed are the only means that can be changed by the driller while making a hole. Therefore it has been always tried to define an optimum range for drilling parameters as key components of the vibration reduction and the rate of penetration management process. A fully automated laboratory scale drilling rig (CDC miniRig) and vibration sensor sub are used to monitor and record drilling parameters such as weight on bit, rotary speed and vibration of drill string among others. Based on different ranges of weight on bit and rotary speed, drilling data and vibration readings are analyzed and the effects of drilling parameters due to vibrations are better understood. Parameter ranges based on the experimental results leading to minimum vibration and optimum rate of penetration are presented.