As a basic component to ensure the stable operation of the crane, the material selection of the crane rail is crucial. The right material can not only ensure the safe operation of the equipment, but also extend the service life of the rail and reduce maintenance costs. Many factors need to be considered when selecting.
Selection based on load-bearing capacity
The weight of the heavy objects hoisted by the crane varies greatly, and the load-bearing capacity is the key to selecting the rail material. Cranes with large lifting weights and frequent use, such as large port loading and unloading cranes, need to select high-strength materials, such as U71Mn steel. This type of steel contains high carbon and manganese (C=0.15% - 0.8%, Mn=0.6% - 1.5%), and has high strength after rolling. It can withstand huge pressure and frequent impacts, and is not easy to deform or break. If used in a small workshop, a crane with a small lifting weight and infrequent operation, it is sufficient to select a rail made of ordinary carbon steel, which is low in cost and can meet the use requirements.
Consider the need for wear resistance
The rail is subjected to wheel rolling and friction for a long time, and wear resistance directly affects its life. In an environment with complex working conditions and intense friction between wheels and rails, such as metallurgical enterprises, cranes often lift hot steel billets, and the rail temperature is high and wears quickly, so materials with good wear resistance are required. Carbide rails contain special alloy elements, which can greatly improve wear resistance. In some places with good working environment and low operation frequency, the requirements for wear resistance are relatively low, and ordinary material rails can be selected.
Pay attention to environmental adaptability
Environmental factors have a significant impact on rail materials. In high temperature environments, such as cranes in steel plants and glass plants, rails are prone to deformation due to thermal expansion and contraction. Materials with good thermal stability should be selected to prevent performance changes at high temperatures. In chemical companies with humid and corrosive media, rails are prone to corrosion. It is necessary to select corrosion-resistant materials, such as copper-containing carbon steel rails, or perform special anti-corrosion treatment on the surface of the rails, such as hot-dip galvanizing and anti-corrosion paint, to enhance its ability to resist corrosion.
Common rail material types
Common crane rails include QU70, QU80, QU100, QU120 and other specifications. The number after "QU" indicates the width of the rail head. The material is mostly manganese steel, which has good strength, hardness and wear resistance, and is suitable for all types of cranes. Taking QU100 as an example, the head width is 100mm, which can provide better support and strong bearing capacity. It is widely used in the laying of large crane tracks.
Railway rails
Railway rails are divided into heavy rails and light rails. Heavy rails weigh more than 30kg per meter and have high strength. Some heavy rails can also be used for crane rails after special treatment. They are suitable for cranes with large lifting weights and fast running speeds. Light rails weigh no more than 30kg per meter and are made of carbon steel or low alloy steel. They are low in cost and can be used for cranes with small lifting weights and slow running speeds, but their wear resistance and bearing capacity are inferior to crane rails.