Author: Site Editor Publish Time: 2024-08-06 Origin: Site
Crane wheels are typically produced through forging, and smaller crane wheels are often made from forged steel, using high-quality steel of no less than grade 45. For crane wheels that are subjected to heavy loads, alloy steel is used. In certain cases, alloy steel is also employed to reduce the wheel diameter and lower the crane's height.
To enhance the load-bearing capacity and extend the service life of crane wheels, heat treatment is applied to their treads. The required hardness for both the tread and the inner side of the flange is 300-380 HB, with a hardness at a depth of 20 mm from the surface not less than 260 HB. Multiple heat treatment methods are currently available to meet these hardness requirements.
According to the Crane Design Handbook, the wheel flanges of crane wheels endure the lateral pressure of the crane. Approximately 70%-80% of the wheel's travel involves friction against the side of the rail. As a result, flange wear is a primary cause of crane wheel failure. Therefore, during heat treatment, the inner side of the wheel flange must be included in the process. For instance, if the induction coil used for power-frequency quenching is too narrow, the inner side of the flange may fail to meet the required hardness standard.
Achieving the correct tread hardness in the manufacturing process can be challenging. Excessive hardness can cause severe rail wear, while insufficient hardness at a depth of 20 mm can result in significant wear on the crane wheels themselves. From our extensive experience, using cast steel or carbon steel with a carbon content below 0.5% leads to a hardened layer depth on the tread that fails to meet the required standards.
Some forging manufacturers, due to equipment limitations or cost considerations, may use surface flame hardening for the heat treatment of crane wheels. However, this method only produces a hardened layer of 2-5 mm depth, which leads to considerable surface brittleness. During operation, cracks may develop on the tread, causing the hardened layer to detach, rendering the wheel unusable. This method is not recommended.
Ma'anshan Tianjun Machinery Manufacturing Co., Ltd. has 15 years of experience in precision forging. Based on different product structures, quantities, and material requirements, we select the appropriate forging process. Our rigorous production processes and strict testing procedures ensure that every step of the production is carefully controlled for each product. With superior product quality and service, we have earned the trust of both domestic and international customers. Interested parties are welcome to contact us.
