Abstract: An approach for increasing the rate of penetration (ROP) of roller cone bits is presented. The proposed approach is based on 3D finite element method (FEM) simulation as well as field test results that were carried out on the Aghajari formation located in the southwest of Iran. In order to reduce the operation time by improving roller cone bit design, the FEM simulation of the complex nature of the contact between the roller cone bit and the formation was performed and the obtained results were compared with the field test data. Results were employed to improve the geometry of the bit profile. Based on the improved design, a roller cone bit was manufactured and employed in the field experiment to assess the performance and to verify the numerical simulation. The results show a positive effect of the improvements on the ROP which leads to a considerable reduction in drilling costs.

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