Grab bucket refers to a special tool for cranes to grab dry bulk cargo. The container space is composed of two or more openable and closable bucket-shaped jaws. When loading, the jaws are closed in the material pile, and the material is caught into the container space. When unloading, the jaws are in the material pile. It is opened under the suspended state, and the material is scattered on the material pile. The opening and closing of the jaw plate is generally controlled by the wire rope of the hoisting mechanism of the crane. Grab bucket operation does not require heavy manual labor, which can achieve high loading and unloading efficiency and ensure safety. It is the main dry bulk cargo handling tool in ports. According to the types of working goods, it can be divided into ore grabs, coal grabs, grain grabs, timber grabs, etc.