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The characteristics of rock drilling tools, H22 drill rod manufacturers explain to you
H22 drill rod manufacturers believe that carbon tool steel with a carbon content of 0.70%~1.0% is a kind of drill steel used for shallow hole drilling at home and abroad in the early days. It can still meet the needs of drilling projects at that time when matched with low-frequency, low-impact power rock drills. With the development of rock drills, the fatigue strength of carbon tool steel is increasingly unable to meet the requirements of rock drilling.
Sep 27th,2024
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H22 drill rod manufacturers believe that carbon tool steel with a carbon content of 0.70%~1.0% is a kind of drill steel used for shallow hole drilling at home and abroad in the early days. It can still meet the needs of drilling projects at that time when matched with low-frequency, low-impact power rock drills. With the development of rock drills, the fatigue strength of carbon tool steel is increasingly unable to meet the requirements of rock drilling.
Although 0.15%~0.30% vanadium or 0.47%~0.70% chromium is added to carbon tool steel to improve the hardenability, grain refinement and toughness of this steel, its usage is decreasing and will eventually be replaced by alloy drill steel.H22 drill rod manufacturers believe that China's medium and large diameter drill rods, 35Si. MnMc, V drill steel is used to drill medium and deep rock holes. It is only normalized and has a low average service life. After chemical heat treatment and surface shot peening, the average drilling life can reach 10,000 meters/root.However, in the past 10 years, foreign advanced high-frequency and high-power hydraulic drilling equipment has entered China in large quantities.H22 drill rod manufacturers believe that the plasticity, cyclic toughness and fatigue resistance of steel have an impact on the rolling quality. Non-metallic inclusions in steel are the source of fatigue cracks, and at the same time destroy the continuity of the matrix and cause stress concentration. The larger the inclusions, the more the fatigue strength decreases. The gas and non-metallic inclusion content of vacuum smelting is much lower than that of ordinary smelting, so its fatigue strength is also much higher. Therefore, the smelting of modern hollow steel adopts the methods of arc furnace smelting, vacuum degassing and refining outside the furnace to improve the purity of steel as much as possible.H22 drill rod manufacturers believe that the rolling quality of drill tool raw materials is closely related to the advanced degree of rolling technology and equipment. The characteristic of the "alloy cast pipe" method for manufacturing hollow steel is that the alloy steel pipe can be firmly cast in the hollow steel ingot. After rolling, a layer of alloy lining wall can be formed on the inner surface of the hollow steel, which strengthens its inner surface to a certain extent, thereby extending the drilling life of the drill rod. However, during the smelting process, due to the small shape of the steel key, metallurgical defects such as shrinkage cavities and inclusions are concentrated on the surface of the ingot and the interface between the alloy steel pipe and the base steel. After rolling, these metallurgical defects extend into strips and lines, randomly distributed on the cross section of the steel. When the drill pipe is used for drilling, it is easy to produce crack sources under the conditions of scouring and stress corrosion of mineral water. Due to factors such as low drilling accuracy, core loading process and equipment, the liner is poorly bonded to the parent material and local separation is serious. Some are deformed and folded to form sharp corners, causing stress concentration and becoming a fatigue crack source. The above are some knowledge points about rock drilling tools. I hope you can carefully study and understand the relevant knowledge, choose products and equipment that suit your needs, and ensure your own benefits. If you want to know more details, you can contact us. I believe we can give you a satisfactory answer.
