What kind of equipment is the bridge grab ship unloader?

Bridge grab ship unloader is a kind of large-scale bulk cargo unloading equipment designed by Dravo Company of the United States. After continuous improvement, it has been widely used in large-scale new bulk cargo terminals in major ports all over the world since the late 1960s. From the appearance, the bridge grab ship unloader is similar to the shore container crane. Compared with the gantry crane, the bridge grab ship unloader has no complicated rotating mechanism and luffing mechanism. More importantly, it greatly improves the working speed of the grab lifting and closing mechanism on the basis of simplifying the movement, without worrying about the influence of additional loads such as inertia load and yaw load on the stability of the whole machine, which is conducive to the development of equipment in the direction of large-scale and high efficiency. The lifting capacity of large bridge grab ship unloader is generally 50-85 tons, and the working object is large bulk carriers with 200,000-300,000 tons. When used to unload iron ore, the average unloading efficiency can reach 1800 ~ 2500 tons/hour.

When the bridge grab ship unloader works, the grab bucket unloading is actually a dust-raising action. Although at present, water spraying or dust suction devices are installed at the discharge port and material transfer point, and good results have been achieved, the dust generated by bucket unloading can not be completely eliminated at present.

Over the years, countries all over the world are scrambling to develop continuous ship unloaders, hoping to replace grab ship unloaders. However, due to the complex structure, high technical requirements and poor commodity adaptability, the promotion and use of these models are still limited. However, the inherent advantages of grab ship unloader, such as mature and reliable technology and little influence by waves, are still the first choice of bulk ship unloader. Therefore, at present, most of the large-scale bulk cargo loading and unloading ports at home and abroad with large throughput and high operation efficiency still use intermittent bridge grab ship unloaders. It can be predicted that the bridge grab ship unloader will remain the dominant type of bulk cargo unloading operation for a long time to come.