The casing drill bit fractures the formation through rotary cutting or impact and is rigidly connected to the casing string via mechanical or hydraulic mechanisms, allowing the casing to be run into the hole synchronously with the drilling process.

A borehole reamer is a specialized tool used to enlarge the diameter of an existing borehole. It is widely used in oil drilling, geological exploration, and trenchless engineering.

Core drill bits are the core tools for obtaining complete rock core samples in drilling projects. Their design must balance efficient rock breaking, core protection, and adaptability to complex formations.

The hole-starting drill bit is the core tool for establishing the initial hole section in drilling operations. It is designed to cope with complex geological conditions and ensure precise hole opening formation.

These are the core components for achieving efficient rock breaking and precise cuttings removal. Their design directly impacts drilling efficiency, cost, and operational safety. Reverse circulation drill bits employ a dual-channel structure: the outer tube injects high-pressure fluid (air or mud) to drive rock breaking, while the inner tube rapidly extracts rock cuttings to the surface.

Its working principle involves compressed air driving an internal piston to generate high-frequency impact force, which pushes the drill bit to break the rock. Simultaneously, high-pressure airflow enters the impactor through the outer tube, driving the piston and carrying rock cuttings back to the surface through the inner tube, forming a closed, continuous reverse circulation system.

It employs a double-layer hollow structure, consisting of an outer tube and an inner tube. An annular channel is formed between the outer and inner tubes for injecting compressed air or drilling fluid. The inner tube serves as a return channel for cuttings and fluids, transporting bottom-hole debris to the surface at high speed. This enables highly efficient reverse circulation cuttings removal, making it particularly suitable for large-diameter boreholes and complex formations.