The shore container crane is a special crane for loading and unloading container ships at the front of the container terminal. It mainly uses special container spreaders to complete the loading and unloading operations of the container. In order to adapt to the heavy load handling of individual container ships, some shore container cranes are equipped with heavy hooks, and a few port shore container cranes have two functions of container and grab loading and unloading.container crane manufacturers
The main features of the shore container crane:
1. Trolley running and anti-rolling mechanism
The container crane has a long running distance and a high running speed. When the car starts and brakes, the cargo will sway in the direction of the trolley running. The higher the running speed of the trolley, the more severe the sway, which affects the loading and unloading efficiency and the safety of the operation. Therefore, a rocking device must be installed.
2. Lifting mechanism
Bridge grab ship unloaders are usually fully loaded, but the load on the shore container crane hoisting mechanism varies greatly. Since the current cargo load of the container is generally only 50% to 60% of the rated cargo capacity, if the crane’s rated lifting capacity is designed to be 30.5t, when lifting the 20ft container, even the maximum gross weight of the crane is only 67. %. In order to improve the loading and unloading efficiency, the lifting speed is required to vary with the load. If the speed of lifting the rated load is constant, the lifting speed should be increased in inverse proportion when the lifting load is less than the rated load. The general no-load speed is heavy. 2 times or even 2.5 times faster.
3.Drive and power supply
In order to meet the working requirements of the shore container crane and achieve good speed regulation performance, the DC stepless speed regulation system is generally adopted, and each mechanism is driven by a DC motor. There are three ways to supply DC power: the first one is the AC motor DC generator. This method is used more. It works more reliably. The power supply voltage is basically unaffected by the grid voltage fluctuation and is relatively stable. The disadvantage is that the unit is self-contained, the price is high, and the noise is also large. The second type is the thyristor rectification method, which has high electric efficiency, good speed regulation performance, light weight, small floor space and convenient maintenance, but requires large grid capacity and small voltage fluctuation. In addition, the technical level of maintenance is high. The third type is the power supply mode of the diesel generator. It is not affected by the external power supply and improves the mobility of the container crane. It is especially suitable for terminals with inconvenient power supply and can save investment in power supply facilities. The noise is very large and the maintenance of the diesel engine is complicated.gantry crane manufacturers
4. Car operating mechanism
When loading and unloading a container ship, it is necessary to move the big car to the position on the ship, and it does not collide with the adjacent container or the superstructure of the ship. Therefore, the running mechanism of the cart is required to have better speed regulation, micro-motion and braking performance. Therefore, it is usually driven by a DC motor.