Overhead Crane Information

Overhead cranes are a type of bridge crane that runs on elevated tracks. They are widely used in general mechanical manufacturing, coal mines, chemical plants, and other places for material handling and loading/unloading. The working system applies to A3-A7, and the working environment temperature is within the range of -25℃ to 40℃. The lifting capacity ranges from 2t to 550t, and it is suitable for spans of 7.5 to 33.5 meters. The electrical equipment control forms include wireless, wired ground control, and control room control. The bridge of the bridge crane runs longitudinally along the tracks laid on both sides of the elevated structure, and the hoisting trolley runs laterally along the tracks laid on the bridge, forming a rectangular working range. This allows full utilization of the space under the bridge to lift materials without being hindered by ground equipment.

A bridge crane is generally composed of a hoisting trolley, a bridge running mechanism, and a bridge metal structure. The hoisting trolley is made up of a hoisting mechanism, a trolley running mechanism, and a trolley frame. The hoisting mechanism includes an electric motor, a brake, a reducer, a drum, and a pulley block. The electric motor drives the drum through the reducer, causing the steel wire rope to wind onto or off the drum to lift or lower the load. The trolley frame is a frame that supports and installs the hoisting mechanism and the trolley running mechanism and is usually a welded structure.

The running mechanism on a bridge crane is composed of an electric motor, transmission device, brake, and wheelset. The task of the running mechanism is to make the crane or trolley move horizontally for transporting goods or adjusting the working position, and at the same time, it can transfer the load acting on the crane or trolley to the foundation supporting them. The running mechanisms of land cranes are divided into two types: trackless running and track running. The running mechanism on a bridge crane belongs to the latter category. According to its structural characteristics, the running mechanism can be divided into two types: modular and integral. According to the driving method of the driving wheels, the running mechanism can be divided into two types: centralized drive and separate drive. Centralized drive is driven by one electric motor for the driving wheels on both tracks, while separate drive is driven by separate electric motors for the driving wheels on each track. The running mechanism is driven by the friction force between the driving wheels and the track. To ensure sufficient adhesion force, the running mechanism should have enough driving wheels. The driving wheels should be properly arranged to ensure sufficient wheel pressure in any case, otherwise it will affect normal operation.

 

 

Steel wire ropes are indispensable major components for lifting machinery and equipment, as well as for hoisting and binding operations. They are widely used as lifting ropes, luffing ropes, traction ropes, hoisting ropes, etc. No matter what kind of application the steel wire rope is used for, if the wrong type is selected, the usage method is unreasonable, safety checks are lacking, and maintenance is not emphasized, or even worse, it is still used after reaching the scrapping standard, major accidents may occur due to damage or breakage of the steel wire rope. Especially for the use of electric hoists with steel wire ropes, the selection of steel wire ropes should be given more attention.

 

1. For hoisting molten or hot metals, steel wire ropes with asbestos cores or other high-temperature resistant cores should be used.
2. In outdoor, humid, or corrosive environments, galvanized steel wire ropes should be selected.
3. For lifting equipment steel wire ropes that pass through pulleys and hoisting accessory drum mechanisms, wire contact steel wire ropes should be preferred. This is because wire contact steel wire ropes have smaller contact stress between wires, less wear, better flexibility, and relatively longer service life.
4. For cranes that lift heavy loads or have multi-layer wound steel wire ropes, non-rotating, non-loosening right-lay alternate-lay steel wire ropes are recommended. This type of steel wire rope has the twisting tendencies of strands and ropes canceling each other out, making it less likely to rotate or loosen when lifting heavy objects.