It is a common fault that the main beam of the double girder crane sinks in use. What are the causes of the main beam sinking of the double girder crane
1. Various parts of the metal structure of the double girder crane have different directions and properties of stresses. Some of these stresses come from the load, while others are caused by the manufacturing process, welding seams and uneven shrinkage of the metal near them. During the use of the crane, these stresses tend to become uniform and disappear, thus causing plastic deformation of the structure
2. The influence of crane transportation, storage and hoisting, as well as unreasonable transportation, storage, hoisting and installation, can cause the deformation of bridge structure.
3. The influence of the use of double girder crane is designed under certain conditions. The unreasonable use of overload, eccentric load, etc. will cause bridge deformation. For example, a 75t double girder bridge crane in a factory has caused the main girder to sink 40mm within 3 years due to frequent overload.
4. The influence of repair method is gas cutting or welding on the cable tray. Uneven heating without taking any measures to prevent deformation will also cause cable tray deformation. The single girder crane has two operation modes: ground and air. There are two kinds of ground operation: handle operation with cable and handle operation with remote controller; Air operation refers to the operation in the cab. There are two types of cab: open type and closed type, which can be divided into left or right installation according to the actual situation. There are two types of entrance direction: side and end to meet the user's different needs.
5. The high temperature affects the sinking of the main beam of the double girder bridge crane used in the hot processing workshop, which is more common and serious than that used in the cold processing workshop. The reason is that the smelting radiation heat will cause the temperature of the lower cover plate of the main beam to be higher than the temperature of the upper cover plate, so that the increase of the lower cover plate is greater than the upper cover plate, which will cause the natural reduction of the camber of the main beam under the load.
