rack (and pinion)It is one of the most important basic transmission components in gear transmission devices. Its load-bearing capacity and service life are important indicators of the level of manufacturing technology of racks. Large-module gear racks in existing mining equipment and metallurgical equipment such as forging and rolling mills have a tooth profile accuracy of medium-grade 8 or 9 according to the national standard (GB1009-88), a tooth surface hardness of medium-grade HB (350), and a tooth surface roughness Ra requirement of 3.2-1.6 μm. Milling is perfectly adequate for finishing the tooth profiles of these large-module gear racks to meet the requirements of the product design drawings. In recent years, hard-tooth-surface gear racks have appeared in some special products. These gear racks have a tooth profile accuracy equivalent to higher grades 7 or 8 of the national standard (GB1009-88), a tooth surface hardness of HRC55 or higher, and a tooth surface roughness Ra requirement of 0.8 μm. For the finishing of large-module hard-tooth-surface gear racks, due to the limitations of existing grinding equipment's machining dimensions, special high-hardness carbide tools are currently used for milling, which is costly and inefficient.