In mining, tunnel construction, geological exploration, and other fields, rock drilling tools are essential construction tools, and their development history has witnessed the continuous progress and innovation of engineering technology. This article will take you on a journey through the history of rock drilling tools, exploring their development and future trends and unveiling the infinite possibilities in this field.
The development history of rock drilling tools
Early development
Initially, the quality of hollow steel was not high, but through continuous research and experimentation by scientists, its quality has significantly improved. By 1920, the emergence of high manganese steel cores made this material widely used in Europe and Japan. At the same time, people also solved the anti-corrosion problem inside the water holes through the SR method (phosphating, waxing).
Development of drill rod technology
To further enhance the performance of the drill rod, hollow steel undergoes processes such as forging, machining, and heat treatment to be made into a drill rod. To increase its bending fatigue resistance, treatments such as surface shot peening and rolling were applied, resulting in a 30% to 40% increase in the service life of the drill rod. By the late 1940s, cross-forged brazing steel specifically designed for hard rock impact drilling emerged.
From 1947, integral drill rods with carbide welding began to be widely used. This kind of drill rod not only has a high effective utilization rate of impact energy and good rock-breaking effect but also discharges powder promptly, reducing repeated crushing, thereby increasing the rock drilling speed. By eliminating the weak link between the bit and the drill rod, they enhance the service life of the rock drilling tool, improve working conditions for workers, save steel, and boost comprehensive technical and economic benefits.
Material development
With the application and promotion of hydraulic rock drills, the stress conditions of rock drilling tools have become more stringent, which also makes carbon steel gradually replaced by alloy steel. Materials like high-carbon chromium-molybdenum steel, medium-carbon nickel-chromium-molybdenum steel, and low-carbon nickel-chromium-molybdenum steel are widely available due to their excellent performance.
Innovation in connection methods
The connection method between the bit and the drill rod is also a crucial area in the development of rock drilling tool technology. According to ISO international standards, large-diameter drill bits mostly use threaded connections, while small-diameter drill bits mainly use cone connections. There are three types of threads for threaded connection bits: corrugated, anti-zigzag, and trapezoidal, each with its own unique characteristics and applicable scenarios. The corrugated thread has a fixed pitch of 12.7mm. As the thread diameter increases, the helix angle decreases, the thread surface pressure increases and disassembly is difficult. It is only suitable for thread diameters less than 32mm. The anti-zigzag thread was proposed by Gardner-Denver Company in the United States, also known as GD thread. As the thread diameter increases, the pitch of the trapezoidal thread also increases, while the helix rise angle remains relatively consistent. Additionally, the flank contact length is more than that of corrugated threads, enhancing thread stress conditions and loading/unloading performance. Trapezoidal threads are commonly employed for thread diameters exceeding 38mm due to their ease of disassembly and extended lifespan.
Diversification of rock drill bits
Rock drill bits come in some various shapes and types, including blade drill bits and button bits such as chisel bits, cross bits, X-bits, and three-edged blades. Each of these drill bits has its advantages and is suitable for different types of rocks and rock drilling scenarios.
The chisel bit is easy to manufacture and grind and has a good drilling effect in solid and dense rock formations.
Cross or three-blade drill bits can drill smoothly in rock formations with developed joints and have fewer stuck problems. The position of the three-edged drill bit and the cemented carbide piece increases the cross-sectional area of the powder discharge ditch, improves the powder discharge condition, increases rock drilling efficiency, and reduces the amount of cemented carbide.
The button bit has the advantages of wide adaptability, fast chisel speed, round and straight blast holes, long service life without grinding, and improved working conditions. It has developed rapidly and has many structural forms. It has formed a complete series, adaptable to various mineral rocks and machine models, and will gradually replace the cross bit.
To meet people’s different needs, people have also developed types such as guide bits, reaming button bits, and retract button bits. These bits play an important role in specific application scenarios.
The prospect of rock drilling tools
With the continuous advancement of global infrastructure construction and mineral development, the market demand for rock drilling tools will continue to grow. At the same time, with the advancement and innovation of science and technology, the performance and quality of rock drilling tools will be further improved. The following is the outlook for the prospects of rock drilling tools:
Continuous growth of market demand
With the continuous acceleration of global infrastructure construction and the development of mineral resources, the market demand for rock drilling tools will continue to grow. Especially in some developing countries and regions, the demand for infrastructure construction will be more vigorous, providing a broad development space for the rock drilling tool market.
Technological innovation to promote industrial upgrading
With the continuous advancement and innovation of science and technology, the material, technology, and intelligence level of rock drilling tools will undoubtedly undergo further improvement. It will promote the development of the rock drilling tool industry, improve product performance and quality, and meet higher market demands. At the same time, technological innovation will also drive the development of related industrial chains and promote the prosperity of the entire industry.
Green environmental protection becomes the development trend
With the continuous improvement of global environmental awareness and the promotion of policies, green environmental protection will become an essential trend in the rock drilling tools’s development. In the future, rock drilling tools will pay more attention to environmental protection and energy-saving design, using environmentally friendly materials and energy-saving technologies to reduce environmental pollution and energy consumption. At the same time, enterprises will also pay more attention to social responsibility and promote the green development of the entire industry.
Personalized customization will become the trend
With the continuous changes in the market and the diversification of needs, personalized customization will become an important development direction of rock drilling tools. In the future, the production of rock drilling tools will pay more attention to customer needs and market changes and flexibly adjust product design and manufacturing processes to meet the needs of different customers. At the same time, the application of digital and network technology can realize intelligent management and optimization of the production process and improve production efficiency and product quality.
Strengthening of international cooperation and exchange
With the acceleration of globalization and the development of international trade, international cooperation and exchanges will become an essential trend in the development of rock drilling tools. Companies from various countries will jointly promote technological innovation and market expansion of rock drilling tools by strengthening cooperation and exchanges. At the same time, international cooperation will also aid companies in understanding the needs and trends of the global market, thereby enhancing the international competitiveness of their products.
Conclusion
The development of rock drilling tools is a process of continuous innovation and progress, and every step embodies the wisdom and sweat of scientists and engineers. In the future, with the development of science and technology, rock drilling tools will be more advanced, efficient, and environmentally friendly, making more contributions to infrastructure construction.
