Crane traveling crane wheel forgings | Analysis of forging process for 35CrMo and 40Cr alloy steel

Crane traveling crane wheel forgings | Analysis of forging process for 35CrMo and 40Cr alloy steel

Crane, hoist, and crane are core equipment for lifting and transportation. The wheels, which bear heavy loads, withstand impacts, and undergo repeated starting and stopping, are the key stressed components. They work in environments with heavy loads, alternating loads, and friction and wear. They require extremely high requirements for material strength, toughness, quenching and tempering properties, and fatigue resistance. 35CrMo and 40Cr alloy steels, with their excellent comprehensive mechanical properties, have become the mainstream materials for crane wheel forgings. Tongxin Forging Factory has been deeply engaged in the field of large-scale alloy steel forging. Relying on mature forging processes and a 15,000-ton large-scale forging equipment, it specializes in customizing 35CrMo and 40Cr hoist wheel forgings. It strictly controls the entire forging process to ensure the high strength, resistance to impact, and resistance to cracking and deformation of the wheels.

35CrMo and 40Cr are medium-carbon alloy structural steels, suitable for different tonnage lifting equipment. 40Cr has good quenching and tempering properties, high strength, and good wear resistance, and is suitable for small and medium-sized hoists, light and medium-sized cranes. It has a high cost-performance ratio. 35CrMo, with molybdenum elements, enhances toughness and fatigue resistance, and has better resistance to high-temperature impact and fracture. It is mostly used for heavy-duty crane wheels, bridge cranes, and龙门 cranes with heavy loads， capable of withstanding frequent lifting impacts and long-term continuous operation， and is less likely to have problems such as wheel rim cracking or tread peeling.

For 35CrMo and 40Cr crane wheels， Tongxin Precision Forging Factory adopts standardized integral free forging + die forging forming processes， controlling each step from raw materials to finished products. The first step is to strictly select materials， using high-quality steel billets from Baosteel， conducting spectral and flaw detection tests before entering the factory， eliminating impurities， porosity， and cracks， ensuring the purity of the material from the source. During the forging process， high-temperature heating is adopted， precisely controlling the heating temperature and holding time to avoid coarse grain formation and overheating and overburning. With a 15，000-ton press， the steel is forged with powerful force， making the internal metal flow lines continuous and dense， reducing grain size， eliminating internal pores and shrinkage porosity， and significantly improving the overall density and impact resistance of the wheels. The overall forging process is better than casting wheels in terms of internal structure uniformity and bearing capacity， effectively avoiding fracture hazards under long-term heavy loads.

Post-forging heat treatment is the core环节 of alloy steel wheel performance. Tongxin Forging Factory adopts the normalizing + tempering treatment process. After tempering 40Cr wheels， a uniform tempered bainite structure is obtained， with moderate hardness， wear resistance， and pressure resistance； 35CrMo wheels are precisely tempered to enhance toughness and fatigue strength， suitable for heavy-duty loading conditions. After heat treatment， the wheels undergo tempering stabilization to eliminate forging internal stress and prevent deformation and cracking in later use.

In the finishing and non-destructive testing stages, the wheel tread, rim, and axle holes are processed using lathes and milling machines to ensure dimensional accuracy, coaxiality, and surface finish. Each wheel undergoes ultrasonic and magnetic particle testing to thoroughly check for internal cracks and surface defects. Only after meeting the hardness standards can the wheels be shipped, which complies with the safety usage standards for lifting equipment. Tongxin Forging can customize various specifications of crane, crane, and crane wheel forgings as per customer requirements. It offers one-stop services for rough, semi-finished, and finished processing of raw materials. Non-standard and special-shaped wheels can also be customized. With stable forging processes, strict quality control, and rapid delivery capabilities, the products are widely used in factory cranes, port gantry cranes, bridge cranes, and construction machinery lifting equipment, providing reliable guarantees for the safe and stable operation of lifting equipment.