Cone Crusher step plate

The cone crusher step plate (main shaft step plate) is a key load-bearing and structural component, primarily responsible for axial load transmission (handling several tons in medium-sized crushers), positioning/guiding the main shaft and moving cone, and providing mechanical support to reduce vibration.​ Structurally, it is a disc-shaped part made of high-strength alloy steel (40CrNiMoA/35CrMo) with a 30–80 mm thickness. It features a central hole (±0.05 mm tolerance) for main shaft fit, step features (10–30 mm height, 20–50 mm width) interacting with thrust bearings, and 8–24 mounting holes for high-strength bolts (grade 8.8+).​ Manufacturing involves:​ Casting: Alloy steel melting (1500–1550°C), sand mold casting, followed by normalization (850–900°C) and quenching-tempering (820–860°C quenching, 500–600°C tempering).​ Machining: Rough turning (2–3 mm allowance), precision grinding (Ra0.8–1.6 μm surface finish, ±0.02 mm dimensional tolerance), and drilling/tapping (±0.1 mm positional tolerance for holes).​ Surface treatment: Shot-blasting and anti-rust coating (80–120 μm).​ Quality control includes material testing (chemical composition, tensile strength ≥980 MPa for 40CrNiMoA), dimensional inspection (CMM and gauges), NDT (ultrasonic/magnetic particle testing for defects), and assembly/performance validation to ensure fit and stability