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The low rate of penetration (ROP) and severe wear of polycrystalline diamond compact (PDC) bits are one of the main problems restricting the exploration of deep oil and gas resources when drilling strongly abrasive formations. As a rock-breaking tool that breaks rocks in the way of diamond exposure, the impregnated diamond bit has the characteristics of high stability, long service life and high drilling speed, which are considered to improve the drilling efficiency of strong abrasive formations. one of the effective ways. However, the drilling parameters and rock abrasiveness of the impregnated drill bit have a very significant impact on the wear rate of the impregnated diamond bit. If the drilling parameters are not designed properly, the bit will be severely worn and the service life will be too low. At the same time, there is a lack of research on the wear equation of diamond-impregnated drill bits, which cannot predict the wear rate of the drill bit and the life of the drill bit well. Therefore, this paper analyzes and summarizes the experimental data of the influence law of drilling parameters and rock abrasiveness coefficient on the wear of impregnated diamond bits, and establishes a formula based on the quantitative relationship between wear rate and WOB per unit area, rotary speed and rock abrasiveness. The impregnated diamond bit wear model provides a theoretical basis for the life prediction of the impregnated diamond bit in field drilling operation. [ABSTRACT FROM AUTHOR]

Optimal parameter drilling has been an effective means to improve drilling efficiency for years now. It is an important theoretical basis to build the rate of penetration (ROP) model and wear model of PDC bits for optimal parameter drilling. However, several authors have focused on the ROP models for PDC bits, only a few researchers have attempted to study PDC bit wear models. Thus, the aim of this research is to establish a quantitative relationship between the PDC cutter wear rate and different influencing factors, and then to determine the overall PDC bit wear model. First, the influence of different factors on the PDC wear rate and the general relationship equation were investigated through a single-variable VTL test. Secondly, a new mathematical model is constructed by fitting multifactor orthogonal experimental data to predict the PDC cutter wear rate by considering the factors of WOB, RPM, rock abrasiveness index and dimensionless cutter wear height. Finally, the PDC bit life model was derived based on the IADC bit dull grade evaluation standard and PDC cutter wear rate equation. And the accuracy of the model was verified by field tests in Changchun, Jilin granite formation, which were drilled with three different PDC bit sizes. The results showed that the PDC bit life obtained by the prediction model was well in agreement with the actual field data obtained in bit records, and the margin of error was within 10%. And the PDC bit life model in this paper has a significant theoretical reference value for PDC bit design and improving drilling efficiency. [ABSTRACT FROM AUTHOR]