NM400/NM500 steel pipes are widely used in mining machinery for transporting ore pulp, crushed stone, and other abrasive materials, such as ore conveying pipelines in mines and slurry transport pipes in mineral processing plants, as their high hardness and wear resistance can withstand long-term friction and impact from solid particles to reduce pipe wear and leakage. In engineering machinery, they are applied to manufacture hydraulic support oil pipes for excavators, loader boom oil pipes, and bulldozer hydraulic system pipelines, ensuring stable operation under high pressure and harsh working conditions. They also find use in the building materials industry (for cement raw material transport pipes in cement plants), the coal industry (for coal slime transport pipes in coal preparation plants), and the environmental protection sector (for waste residue transport pipes in waste treatment equipment), serving as a reliable material for wear-prone and high-demand medium transportation scenarios.