What is the difference between roller cone and PDC bit
The difference between roller cone bit and PDC bit: Roller cone bit and PDC bit are two types of drilling bits widely used in oil and gas drilling. The main difference between them is the cuttings removal method and application scenarios.
Roller cone bits use rolling cones to crush the formation and remove cuttings. The cuttings are moved up the borehole by the rotation of the drill string and the movement of the rolling cones. Roller cone bits are suitable for drilling soft formations such as sandstone and shale, because the cutting force is relatively small and the bit does not damage the formation. However, roller cone bits are not suitable for drilling hard formation such as granite, because the cutting force is insufficient to cut through the hard formation.
PDC bits use polycrystalline diamonds to cut through the formation. The cuttings are removed by the rotation of the drill string and the abrasion of the diamonds. PDC bits are suitable for drilling hard formation such as granite, because the cutting force of the diamonds is very high and can cut through hard formation. However, PDC bits are not suitable for drilling soft formation such as sandstone and shale, because the diamonds will damage the formation and reduce the drilling efficiency.
For soft formation, roller cone bits are more suitable, while for hard formation, PDC bits are more suitable. the drilling speed, cost and wear of the bits are also factors to consider when choosing a drilling bit