Rafid Abbas
University of Leeds, UK
Title: A new approach for predicting the wear of roller-cone bits using the Concept of three body abrasive wear
Biography
Biography: Rafid Abbas
Abstract
Predicting the wear of drill bits is essential for all oil and gas industries to maximise drilling efficiency and reduce loss in money and time. Typically, this problem has been handled by evaluating the specific energy of the drill bits at drilling formation intervals along with well logs and geophysical analysis. Although these techniques could provide good indication of the bit tooth wear, lack of consideration of material properties of rock and bit in the previous wear models, the bit balling phenomena and high level of vibration of the drill bit might give misleading results that affect the reliability of these techniques.
The present study focused on the determination of the wear of roller-cone bits taking into account the hardness of the rock formation and the materials forming the drill bit, along with other drilling parameters, such as rotary speed, rate of penetration, weight on bit and the time required to drill a specific interval.
The bit wear obtained from the formula developed in this work is compared to the qualitative in-situ bit tooth wear for various drilled formation intervals of a number of wells in the south of Iraq for which a close match is observed.
The new approach for bit wear determination could be used as a trending tool to evaluate the status of the drill bits or predicting the wear of roller-cone bits. The study could potentially be extended and applied to other types of drill bits such as Polycrystalline Diamond Compact (PDC) bits.