The ship crane is the device and machinery for loading and unloading goods provided by the ship, mainly boom device, deck crane and other loading and unloading machinery.
There are two ways of loading and unloading goods with boom device, namely single-rod operation and double-rod operation. Single-rod operation is to use a boom for loading and unloading of goods, boom after lifting the goods, pulling the drawstring so that the goods with the boom swing outboard or cargo hatch, and then put down the goods, and then turn the boom back to the original position, so round-trip operation. Loading and unloading each time to use the rope swing boom, so low power, labor intensity. Double-rod operation with two booms, one placed over the cargo hatch, the other outboard, the two booms with a rope fixed in a certain operating position. The lifting ropes of the two booms are connected to the same hook. Only need to receive and put two starting cables respectively, you can unload the goods from the ship to the pier, or perhaps load the goods from the pier to the ship. The loading and unloading power of double-rod operation is higher than that of single-rod operation, and the labor intensity is also lighter.