Maintenance Methods for PDC Drill Bits
During drilling operations, a PDC drill bit works together with the rig and related drilling equipment and is the only core tool that directly cuts rock. As such, it has a finite service life. After each borehole is completed, timely maintenance is essential. Proper upkeep not only extends bit life but also ensures efficient performance in subsequent drilling work.
1. Maintenance of Electroplated Layer
Scientific and timely maintenance can effectively extend the service life of electroplated diamond bits while significantly reducing overall drilling costs. After each operation, clean the matrix area at the bit head as soon as possible, and carefully inspect for abnormalities such as matrix detachment or cracking of the bit body. At the same time, check the wear condition of the diamonds on the cross-section. If the bit can no longer drill normally or perform core jamming/catching properly, it should be replaced immediately.
If the bit body and matrix remain intact but drilling efficiency drops significantly or slipping occurs, one solution is to switch to a 6°–8° diamond bit. Another is to manually expose the cutting edges on the bit matrix to improve penetration rate. To keep an electroplated bit in optimal drilling condition each time it is used, thorough cleaning and detailed inspection after every job are mandatory.
2. Overall Bit Maintenance
PDC bits fall within the category of geological diamond bits and are available in two types: coring and non-coring. Regardless of type, regular maintenance is required.
After each borehole operation, first inspect wear on the hard-alloy sections of the bit. If wear on the outer gauge-protection strips exceeds two-thirds, continued use will not only reduce drilling efficiency but also accelerate wear of the core barrel and drill rods. In this case, replace the bit promptly or reweld the alloy section.
Next, inspect wear of the cutting PDC elements on the bit head. If the remaining cutter material is less than one-fifth, continued use is strictly prohibited. The cutters must be replaced in time, or the bit should undergo re-machining/deep re-turning treatment as required.
Although diamond bit prices have dropped significantly in recent years, controlling drilling cost remains a core objective across the industry. Timely maintenance and servicing of bits can effectively reduce overall cost, lower the probability of drilling accidents, and provide strong support for safe and efficient drilling operations.
