Excavator, also called diging machinery (excavating machinery), it is to use the bucket to handle the material above or below the bearing machine, and then load on transport vehicles or discharge to pile-yard earthwork machinery. Excavator handle the main material of soil, coal, silt and soil or rock after the loose. From the development of engineering machinery in recent years, the development of excavator is relatively fast, and excavator is one of the main  engineering construction, the correct selection also becomes even more important.