In mining, tunnel construction, geological exploration, and other industries, top hammer rock drilling equipment has gained widespread adoption owing to its efficiency and reliability. However, the market offers a variety of top hammer rock drilling equipment, each with its strengths. This article aims to provide detailed insights into several common types of top hammer rock drilling equipment, comparing their advantages and disadvantages. We will help you better understand the various types of products so that you can choose the most suitable equipment for your needs.
Top hammer rock drilling equipment encompasses various types tailored to different application scenarios and engineering requirements, including pneumatic rock drills, surface hydraulic rock drilling rigs, underground mining drilling rigs, and underground excavation drilling rigs.
Pneumatic rock drill
A pneumatic rock drill is an impact drilling machine powered by compressed air. Classified by the support method, there are mainly hammer hand, gas leg, upward, and guide rock drills.
Advantage:
- Simple structure, easy maintenance, and flexible operation.
- Suitable for a variety of rock drilling scenarios.
- Low operating costs and good economic benefits.
Disadvantages:
- Long-term use will lead to the consumption of compressed air and affect the improvement of the energy parameters of the rock drill.
- In mass production, the production capacity of pneumatic rock drills can not meet the requirements of mine production growth.
- Pneumatic rock drills require specialized compressors and airlines, with higher repair and maintenance costs.
- Manpower support is required during construction, and the operation process is slow. Prolonged operation may lead to operator fatigue.
- Because of the need to generate a higher air pressure when working, it will produce high noise, which will cause damage to the operator’s hearing.
Features of equipped rock drilling tools
- The drill rod typically has a hexagonal shape, with frequent sizes being H22 and H19, while H25 is less commonly used. Connection methods with the drill head include integral drill rods, tapered drill rods, and threaded drill rods. Lengths range from 400mm to over 8000mm.
- The drill bit commonly connects via one-piece and taper connections, while threaded connections like R22 and R25 are less common. The drill bit diameter typically ranges from 26mm to 45mm.
Surface hydraulic rock drilling rigs
Surface hydraulic rock drilling rigs offer high drilling speed and efficiency. Equipped with multiple drill rods, they can conduct multi-point rock drilling simultaneously. These rigs find wide applications in hydropower, mining, quarrying, and other projects. Key brands include Atlas Copco, Sandvik, and Furukawa.
Advantage:
- Fast drilling speed and high efficiency.
- Multi-point simultaneous operation is possible to improve productivity.
- Good stability and ability to work in complex terrain.
Disadvantages:
- The equipment is large and requires ample working space.
- Maintenance costs are high.
Features of equipped rock drilling tools
Drill rod
- Surface hydraulic rock drilling rigs drill multiple drill rods (some models have up to 8 drill rods). Commonly used round drill rods, while hexagonal drill rods are less prevalent.
- The threads at both ends are the same, with commonly used T45, T51, and T38, while less frequently used ones include R32 and T60.
- The commonly used lengths of drill rods are 3660mm and 3050mm, while less frequently used lengths include 2435mm and 4265mm.
Rock drill bit
- Commonly used button bits have T45 threads of 76mm and 89mm, with 102mm being the limit. T51 threads are available in 89mm, 102mm, and 115mm is the limit. T38 threads are available in 64mm and 76mm, with 89mm being the limit.
- T60 thread button bits are not commonly used and are available in 102mm, 115mm, 127mm, 140mm, and 152mm diameters.
- R32 thread with optional cross bit and T38 thread with optional X-bit for drilling in shallow, friable rock formations.
- The above threads can be equipped with reaming button bits and retract button bits.
Underground mining drilling rig
Underground mining drilling rigs are primarily employed for rock drilling in large underground metal mines during ore mining. The main models include Simba1254/1257/1354, manufactured by Atlas Copco of Sweden.
Advantages:
- High safety performance, suitable for underground operations.
- Strong adaptability and can work stably in complex environments.
- Flexible operation, easy to adjust drilling direction and depth.
Disadvantages:
- Limited by the underground environment, its power and drilling speed may not be as good as open-pit equipment.
- The requirements for operator skills and experience are relatively high.
- Equipment cost is high.
- Maintenance and maintenance are relatively complicated.
Features of equipped rock drilling tools
Drill rod
- Most of them use round drill rods and rarely use hexagonal drill rods. The threads at both ends of the drill rod are the same. Commonly used threads include T38, T45, T51, and R32, while less commonly used ones include HL38, ST58, and ST68.
- The length of the drill rod is typically below 1830mm. Common lengths include 1525mm and 1830mm, while less frequent lengths are 1220mm.
Rock drill bit
- Commonly used button bits have T45 threads of 76mm and 89mm. T51 threads are available in 89mm and 102mm. T38 threads are available in 64mm and 76mm. R32 threads are available in 51mm and 64mm.
- Button bits with ST58, ST68, and HL38 threads are not commonly used. For the ST58 thread, the drill bit diameter is generally 89mm. For the ST68 thread, the drill bit diameter is generally 89mm or 115mm. Regarding the HL38 thread, the drill bit diameter is generally 64mm, 76mm, and 89mm.
- The R32 thread can be equipped with a cross bit, while the T38 thread can be equipped with an X-type bit. These configurations are suitable for drilling shallow and easily fractured rock formations.
- The above threads can be equipped with reaming button bits and retract button bits.
Underground excavation drilling rig
The tunnel drilling rig is a kind of engineering machinery that integrates drilling, excavation, loading, transportation, and other functions. It is suitable for tunnel boring, roadway development operation of rock drilling equipment, in mining engineering roadway and tunnel excavation is widely used, especially in large power station underground plants, guide hole excavation, large underground metal mines, large cross-section tunnel boring projects has been the focus of application. There are single-arm, double-arm, and multi-arm designs. The models of famous foreign brands include Boomer351/353 (three-armed) and Boomer281/282 (single-armed) of Atlas Copco of Sweden and DT1130 (three-armed) and DD210/310 (single-armed) of Sandvik of Sweden.
Advantages:
- It has strong drilling ability and is suitable for complex geological conditions.
- Good stability and capable of continuous operation for a long time.
- High degree of automation, reducing the labor intensity of operators.
Disadvantages:
- Equipment cost is high.
- Higher requirements on the technical level of operators and maintenance personnel.
- The requirements for underground space are relatively high, requiring detailed planning and design in advance.
Features of equipped rock drilling tools
Drill rod
- Underground rock drilling rigs generally have only one drill rod, and most use hexagonal drill rods.
- The thread of the drill bit end of the hexagonal shank rod is R25, and the opposite side size of the drill rod is 22mm or 25mm.
- Excavation rigs of well-known brands at home and abroad mainly use R38/T38-H35/H32-R32 ordinary drill rods or MF rods. The thread at the end of the shank is R38 or T38, the opposite side of the drill rod is 35mm or 32mm, and the thread at the end of the drill bit is R32. Commonly used drill rod lengths are 3090mm, 3700mm, 4305mm, 5525mm, 2475mm, etc
Rock drill bit
- For R25 threaded button bits, the diameter range of ordinary button bits is 33-45mm; when using split-type reaming button bits, the drill bit diameter range is 64-89mm; when using cross bits, the diameter range is 33-51mm.
- For drill bits with an R28 thread, the diameter range of ordinary button bits is 37-48mm, with 41mm and 43mm being more commonly used. When using split-type reaming button bits, the diameter range of the drill bit is 64-89mm. When using cross bits, the diameter range is 38-51mm.
- For drill bits with an R32 thread, the diameter range of ordinary button bits is 45-51mm, with 45mm and 48mm being more commonly used. Split-type reaming button bits diameter range of 64-127mm and integrated reaming drill bits diameter range of 76-127mm. Cross-bit’s diameter range is 41-64mm. Optionally, a retract button bit is available with a diameter range of 45-76mm.
Conclusion
Different types of top hammer rock drilling equipment have their advantages, disadvantages, and specific application scenarios. When selecting equipment, it’s pivotal to consider various factors such as project requirements, operating environment, budget, and more. Additionally, regular maintenance and upkeep are essential to ensure the proper functioning and longevity of the equipment. With careful selection and correct use, top hammer rock drilling equipment can significantly improve efficiency and deliver better economic benefits to your project.
