Crane, truck, crane are commonly known as cranes, driving and now we call the crane basically the same. There are basically two types of driving methods: one is concentrated drive, that is, a motor drives a long transmission shaft to drive the active wheels on both sides; The second is to drive separately, that is, the active wheels on both sides are driven by a motor. Medium and small bridge crane more use brake, reducer and motor unit synthesis of "three-in-one" drive mode, large weight ordinary bridge crane for easy installation and adjustment, the drive device often uses universal coupling. The truck connects the lifting items with the lifting mechanism through the lifting device, so as to carry out the loading, unloading, lifting and installation of these items. There are many kinds of pick-up devices. Such as: hook, ring, tie, clamp, jaw, beam, electromagnetic suction cup, vacuum suction cup, grab, container spreader and so on.