A drill bit is a tool that directly works on the rock in the rock drilling tools, and its performance is related to the drilling effect of the entire rock drilling tools. Since the introduction of hydraulic rock drills, the drill bits used with them have also undergone continuous development and improvement, from cross bits and X bits to button bits. Nowadays, the button bit has become the main type of drill bit for hydraulic rock drills, and a relatively complete product series has also been formed in terms of bit structure. Because of the development of hydraulic rock drills, famous foreign rock drilling tools manufacturers still attach great importance to the research of button bits. For example, they have done a lot of research on the design of button structure, the arrangement of the powder discharge groove, the arrangement of the flushing water holes, the matching of gauge and center button as well as the geometry of drill bits and the shape of tungsten carbide button, and have also achieved some experience and results.

Rock drill bit is a tool that works under impact dynamic loads, and its working conditions and stress conditions are all dynamically changing. Therefore, the research and development on the button bit has also experienced a process of continuous improvement.

Button bit for tunneling jumbo

To make the hydraulic tunneling jumbo achieve rapid rock drilling, a series of performance characteristics are required for button bit，such as strong toughness and wear resistance of carbide button, high strength of drill bit steel, effective rock breaking by the arrangement of a button, and the location of flushing water hole and powder discharge slot to adapt to the fast exclusion of rock chips. After the appearance of SR threaded rods and Alpha threaded rods, foreign rock drilling tools companies have also launched several matching button bits.

Atlas Copco’s drill bit for SR threaded rod is called “focus” drill bit, with a diameter range of 33 mm-54 mm. When Sandvik first launched the Alpha threaded rod in 2003, the drill bit is called “CAPP Black Label” drill bit. At the beginning of 2007, Sandvik introduced a new version of Alpha threaded rod with the RT300 series.

Button bits for open-cutting drill jumbo and mining jumbo

Open-cutting drill jumbos and mining jumbos use the extension rod to drill medium-deep holes, usually with a diameter range of 76 mm to 102 mm, up to 152 mm, and a depth of 20 m to 30 m. Nowadays, most open-cutting drill jumbos are equipped with high-power and high-torque hydraulic rock drills, and the drilling speed is about 1.5 m/min. There are higher requirements on the overall strength of drill bit, the wear resistance of carbide button, the straightness of drill hole, and the performance of the rapid discharge of rock debris. In recent years, foreign rock drilling tools manufacturers have made many improvements to drill bits for open-cutting drill jumbo, especially the drill bit with a diameter of 89 mm or more, in terms of the structure of the carbide button, button shape selection, the shape and arrangement of the air holes and powder discharge slots, etc. These improvements have also achieved good results.

From the continuous improvement of drill bits by foreign rock drilling tools manufacturers, we can know that the development of drill bits for drilling is carried out continuously along the lines of research and exploration, practical use, discovery of problems, and improvement. Other rock drilling tools manufacturers can study these developments, combine them with market demand to conduct more in-depth research on products, and explore more characteristic rock drilling tools for drill jumbos. As long as we can ensure the performance and quality of the products, we believe that we will be able to further improve the market awareness of the enterprises and provide a broader space for the development of rock drilling tools.