In engineering fields like mining, geological exploration, or tunneling, the button bit is an essential tool. It undergoes rapid development and finds widespread use. It has high rock-breaking efficiency and can effectively eliminate the blind rock-breaking area at the bottom of the rock hole and avoid repeated breaking of rock chips. The lower limit of drill bit diameter is not restricted, etc. Some technical engineers even argue that the combination of button bits and hydraulic rock drilling rigs is the most effective complement to rock drilling technology today. So, what is a button bit? This article will briefly introduce you to the basic knowledge and application of button bits.
Button bit is made up of a tungsten carbide button inlaid on the drill bit body. Compared with the flake drill bit, the button bit has a free button distribution. According to the drilling hole dia and the rock breaking load, the number and position of the edge and middle button can be reasonably determined, and the drill bit head diameter is not limited. And because it is multi-point crushing, the rock-breaking efficiency is higher. It can not only effectively eliminate the blind area of
Applications
Button bits are widely used in mining, geological exploration, tunnel excavation, and other engineering fields. In these fields, button bits are mainly used for rock drilling and crushing. Due to the unique design of the carbide button, the button bit can better adapt to the hardness and texture of various rocks, thereby increasing drilling speed and crushing efficiency.
Classification of Button bits
According to the connection form of the button bit with the drill rod, it can be divided into three types: taper button bit, threaded button bit, and down-the-hole drill bit.
The taper button bit is mainly used with the pneumatic rock drill and the tapered drill rod. It is a kind of rock drilling tool which is inlaid with cemented carbide on the drill body and is suitable for the taper of the drill bit body and the drill rod. According to the button fixing process, the products are divided into hot insert process tapered bits and cold pressing process button bits. Products are widely used in mining, tunneling, anchoring engineering, quarrying, and other industries.
The threaded button bit is a kind of rock drilling tool that is connected with the threaded drill rod through the drill bit thread to realize the transmission of the impact power and rotational torque of the rock drill to break the rock. It is often used with the hydraulic drilling rig. It is mainly used in underground mining, open-pit mining, and blast furnace opening in steel mills and other fields.
DTH drill bit
The DTH drill bit is connected to the DTH impactor through splines. The trousers are made of high-quality alloy steel that has undergone strict heat treatment, which has good hardness, wear resistance, and impacts resistance. The tungsten carbide buttons are installed at the head of the drill bit through cold or hot insert. Usually, this kind of drill bit is used combining with the submersible impactor to drill rock. It is widely used in the mining of open-pit mines, quarries, hydropower projects, drilling of water wells, etc. According to the shape classification, the DTH drill bits can be divided into the flat face, drop center, and semi-dome.
The applicable application scenarios of different button bits are also different. According to different rock formation conditions, how to choose a suitable button bit?
Selection of cemented carbide grades
Various rock drill bits and geological formations typically correspond to specific cemented carbide grades for optimal compatibility.
- The higher the uniaxial compressive strength value of the rock, the greater the toughness. In order to prevent the blades and teeth from breaking, it is advisable to choose alloys with higher cobalt content and higher strength.
- For brittle rocks with low uniaxial compressive strength but high corrosion resistance, it is advisable to use carbides with lower cobalt content and higher hardness.
- For extremely tough rocks whose uniaxial compressive strength exceeds 300MPa, it is advisable to choose specialized carbide grades exhibiting enhanced toughness and containing 10% to 15% cobalt. However, in cases where the rock is highly abrasive, maintaining a moderate cobalt content is crucial.
Carbide buttons are an important part of the button bit, and their buttons’ shape mainly includes hemisphere buttons, semi-ballistic buttons, and conical buttons.
| Carbide Buttons Type | Application | Advantage | Apply to rock |
| Hemisphere Button | Universal Carbide | Good abrasion resistance | Very suitable for hard rock; Applicable to corroded strata |
| Semi-Ballistic Button | Universal Carbide | Button entry speed is fast | Very suitable for medium hard rock; Suitable for moderately corrosive rock strata |
| Conical Button | Mostly used for small diameter bit | Button entry speed is fast | Applicable to non-corrosive rock strata |
Notice: Generally, the more edge button, the better overall performance, especially in hard rock conditions.
Development trend
With the continuous advancement of science and technology, button bit technology is also constantly developing. The research and application of new button bit materials have become a focal point in the industry. Through the utilization of more advanced materials and manufacturing processes, the new button bit has seen significant improvements in wear resistance, strength, and service life. In addition, with the application of intelligent and automated technology, the drilling efficiency and accuracy of button bits have been further improved.
Conclusion
As an essential drilling tool, button bits play an irreplaceable role in mining, geological exploration, tunnel excavation, and other fields. In future development, with the continuous advancement of science and technology and the continuous expansion of application fields, button bits will surely usher in broader development prospects. It is hoped that readers will actively apply button bits in their practical work, enhancing work efficiency and quality, and making significant contributions to the industry’s development.
