This article distinguishes **PDC cutter chipping** and **insert loss**, two frequently mixed-up bit failures. Statistics from a 15-year bit repair expert show chipping accounts for 55% of scrapping causes and insert loss for 25%. Their failure locations, root causes and fixes differ greatly: chipping means the PDC cutter itself fractures, mainly caused by parameter overload, abrupt formation hardn

This article analyzes four major reasons for frequent breakage of rock drill rods: 1. **Raw‑material defects**: Poor‑quality steel contains impurities and air bubbles. These hidden internal flaws develop into cracks under impact and torsion, leading to premature fracture. 2. **Violent drilling operation**: Forcing against hard rock, empty firing, and operating with bent drill rods subject the

This article addresses a common field issue: PDC bits fail quickly after replacing tricone bits, which is usually blamed on bit quality. In most cases, however, damage results from applying tricone‑based operating habits to PDC bits. Tricone bits work with high weight‑on‑bit for impact‑crushing rock, while PDC bits cut rock by shearing and are sensitive to excessive WOB. When operated within pr