Carbide drill bit break rock by weight on bit and impact load generated by their own rotation. In rock drilling, the drill is subjected to high frequency impact loads, and is subjected to torsion, bending, stretching, compression and other compound stresses, and is subjected to wear and corrosion of rock, rock powder and mineral water and other working media in the environment of high-speed rotary collision.
Most of the cone bits used at home and abroad are tricone bits. The characteristics of this bit are: axial pressure and impact load distribution range is large and uniform, and can make full use of effective space, smooth drilling. The size and shape of the carbide teeth used in the cone drill must be suitable for the characteristics of the rock, requiring good wear resistance, high strength, and not easy to fracture and break. The carbide teeth used in cone bits are mainly spherical teeth, conical ball teeth, wedge teeth, edge wedge teeth and flat top teeth for the wheel back and Java tip.
Generally, cone bits drilling very hard rock mainly use spherical teeth, bit pressure of 892~1339MPa, speed of 50~80r/min; The cone bit used for drilling hard and medium hard rock formations uses cone and ball teeth, the bit pressure is 714~1071MPa, and the rotating speed is 60~100r/min. The cone bits used in soft and medium soft rock formations use wedge teeth or side wedge teeth, the bit pressure is 535~803 mpa, and the speed is 80~120r/min.
Carbide drill bit are divided into four base types: solid carbide bits, carbide indexable blade bits, welded carbide bits and interchangeable carbide crown bits. Each bit has benefits that suit the specific machining premise.
(1) Solid carbide drill bit
(2) carbide indexable blade drill
The drill equipped with carbide indexable inserts can process a wide range of apertures, and the processing depth scale is 2D to 5D(D is the aperture), which can be applied to lathes and other torsion machining machines.
(3) Welded carbide drill bit
Welded carbide bits are made by smoothly soldering a carbide tooth crown on a steel drill body. This kind of drill adopts self-centering geometric edge type, cutting force is small, the workpiece material can achieve excellent chip control, the finished hole profile is good, the dimensional accuracy and positioning accuracy are high, no need to carry out follow-up finishing. The drill is internally cooled and can be used in machining centers, CNC lathes or other high-rigidity, high-speed machine tools.
(4) Carbide tooth crown drill can be replaced
The replaceable carbide crown bit is a new generation of drilling tools. It is composed of a steel drill body and an integral carbide tooth crown that can be changed. Compared with a welded carbide bit, its processing accuracy is 82.5 pounds, but because the tooth crown can be changed, it can reduce processing costs and improve drilling production rate. This kind of bit can obtain the exact aperture size increment and has the self-centering function, and the machining accuracy is very high.
Kehua Cutting Technology (Wuxi) Co., Ltd. is a supplier of high-quality cutting tools with advanced equipment, mainly producing and operating: milling cutter, standard milling cutter, cutting tool, drill, reamer and other products. At present, the company has 25 high-precision CNC grinding machines in Germany, and the introduction of advanced grinding technology from Japan, focusing on the design and development of high-quality tools, for domestic and foreign high-end mold industry, 3C, wind power, auto parts and other machining tools in the field of machining, reflecting a strong competitiveness, especially in the standard milling cutter, deep-hole drilling and high-hard field tool advantages.