Recently, Shanxi Jianlong successfully developed MG700 high-strength anchor steel bars for coal mine support. This is a product independently developed by the company without similar products to refer to, breaking through the technical bottleneck of ultra-high strength and toughness of hot-rolled steel bars, and demonstrating Shanxi Jianlong's research and development capabilities for high-strength special environment steel materials.
After testing, the product has a yield strength of 730Mpa-750Mpa, a tensile strength of 905Mpa-925Mpa, an elongation of 17%-19%, and an impact absorption energy of 34J at room temperature. All technical indicators meet the technical agreement requirements of users.
Compared with ordinary anchor rods, high-strength anchor rods show significant advantages in coal mine support. Especially when the coal mining face encounters a structural section, reinforcement measures are required to prevent the roof from sinking and collapsing. The use of high-strength anchor rods and steel mesh combined support, combined with grouting and shock absorption measures, can significantly improve the stability and bearing capacity of the tunnel surrounding rock, reduce the impact of impact ground pressure on the tunnel, effectively control the deformation and damage of the shaft and large-section chamber, and ensure safe production in the mine.
For typical rock burst mines with a depth of more than 1,000 meters in Henan, Inner Mongolia, Shaanxi, Xinjiang, Shandong, and other regions, ordinary anchor rods with a strength of 500Mpa or less can no longer meet the use requirements. At the same time, the stress corrosion of anchor rods during use is difficult to monitor effectively, posing a huge safety hazard. High-strength anchor rods with a yield strength of more than 700Mpa and corrosion-resistant anchor rods resistant to Cl-, Na+, and CO2 acidity (hydrogen sulfide environment) have shown great advantages in practical applications.
The research, development, and application of MG700 high-strength anchor steel bars have significantly improved the safety of mine construction, improved construction efficiency and quality, and provided important material support for safe deep-well mining in key areas of my country's coal mines.