Journal Article

Performance evaluation and selection of the core drill bits for lunar rock

Zhou, Lang, Wu, Yan, Li, Jiahua, Gao, Zheng, Wang, Xuan, Gao, Mingzhong, Hao, Haichun

2025

Overview

The objective of this study is to systematically examine the drilling efficiency and performance of various core drill bits in lunar rock formation using the discrete element method (DEM) and drilling experiments conducted in a lunar vacuum environment. This research aims to establish a scientific foundation for selecting core drill bits for lunar deep drilling operations. To achieve this, four distinct core drill bits were designed. Subsequently, a numerical model of lunar rock was constructed and the load characteristics and drilling efficiency of each bit during the drilling process were analyzed using DEM. Drilling and coring tests were then performed in both atmospheric and lunar vacuum environments, thereby validating the numerical simulation results and providing a comprehensive evaluation of the actual performance of the core drill bits. The study revealed that the carbide-tipped core drill bit with octagonal prisms design resulted in the core disking due to a significant rise in temperature, underscoring the critical importance of temperature control in maintaining core integrity. While the carbide-tipped core drill bit with cutting edges demonstrates exceptional drilling efficiency and coring quality, its inherent fragility and rapid wear of the cutting edges present considerable challenges for practical application. The diamond-impregnated core drill bit is unsuitable for drilling operations under lunar loads and power limitations due to its high weight-on-bit (WOB) requirements. In contrast, the PDC core drill bit exhibits excellent drilling stability, low rotary torque requirements, minimal temperature-rise effects, and significantly enhanced penetrating speed in the lunar vacuum environment, making it a recommended choice for lunar rock drilling. This study provides substantial theoretical and experimental support for the development of lunar drilling equipment and the formulation of effective drilling strategies. Highlights An improved HMB contact model was used in the numerical simulation calculations. Simulated lunar rock drilling tests were conducted in both atmospheric and vacuum environments, and a comparative analysis was performed with the numerical simulation results. Among the four self-designed drill bits, the PDC bit was identified as the most suitable for lunar rock drilling through comparative selection.

• Publisher: Springer International Publishing,Springer Nature B.V,Springer
• Subject: Carbides / Comparative analysis / Core drill bit / Core drilling / Core sampling / Coring bits / Cutting / Cutting tools / Cutting wear / Design / Diamond drills / Diamond machining / Diamond tools / Diamonds / Discrete element method / Discrete element method (DEM) / Drill bits / Drilling / Drilling and coring tests / Drilling equipment / Drilling machines (tools) / drilling performance / Drills / Efficiency / Energy / Engineering / Environmental Science and Engineering / Foundations / Fragility / Geoengineering / Geology / Geophysics/Geodesy / Geotechnical Engineering & Applied Earth Sciences / Hydraulics / Lunar rock simulant / Lunar rocks / Mathematical models / Mechanical properties / Moon / Numerical models / Performance evaluation / Physical properties / Prisms / Rock / Rocks / Temperature control / Tensile strength / Torque