QZ type grab overhead crane is widely used in power plants, freight yards, workshops, docks, etc., for the loading and unloading of bulk materials. The crane is a heavy-duty working system, and the working level is A6. The rated lifting capacity is generally 5~20t, and there are two kinds of parallel and perpendicular main beams in the opening direction of the grab. The fetching device is a four-rope grab with double drums, which has a simple structure and reliable work. The grapple can be opened and closed at any height. The grab is only suitable for bulk materials in the natural accumulation state, and when grabbing underwater materials or special materials, it must be specially requested at the time of ordering. It can be used indoors or outdoors, and a rain cover device is added for outdoor use.