Second, the characteristics of the scraper: it can complete shovel loading, transportation and paving operations, and has certain compaction and leveling capabilities; Scope of use: mainly used for earthwork with long transportation distance, such as subgrade filling, cutting excavation, large area leveling, etc.
Third, the characteristics of the grader: it is a continuous working machine, which can shovel, transport and unload soil at the same time; Scope of use: (1) borrow soil from both sides of the line and fill the embankment not higher than 1 m; (2) Repair the damaged surface of subgrade; (3) Brush the slope; (4) excavating road grooves and side ditches; (5) Level a large area of site.
Fourthly, excavator features: high efficiency, large output, but poor maneuverability; Scope of application: cutting excavation, high subgrade filling, etc.
Features of loader: high efficiency, simple operation, and working ability of bulldozer and excavator; Scope of application: shovel, push, level, loading and unloading, traction, etc. I found this in a college textbook. I hope it will help you.