我厂主要产品大、中型堆取料机的车轮(φ650mm、φ750mm及φ850mm共三种)踏面技术要求为表面淬火硬度HB340～400,淬硬层6～8 mm。若无感应加热设备时,可采用正体加热淬火,但直径φ850mm车轮,淬后硬度只能达HB290～320。这是因为:一、有效壁厚太大; The main products of our factory are large and medium-sized stacker reclaimer wheels (φ650mm, φ750mm and φ850mm total of three) tread surface technical requirements for surface hardening hardness HB340 ~ 400, hardened layer 6 ~ 8 mm. If there is no induction heating equipment, you can use the body heating quenching, but the diameter φ850mm wheels, hardness after quenching can only reach HB290 ~ 320. This is because: First, the effective wall thickness is too large;