YD-22III Automatic hydraulic Tamping Machine for track maintenance work YD-22III Smart rail tamping machine unit is a renewal product developed by our factory with new material and new technology. It has collected the tamping experience of users at home and abroad. It can do tamping works not only on the ballasted track of concrete sleeper type II and III in China, but also on various kinds of concrete sleepers and steel sleepers in foreign countries.This machine is suitable for tamping operation of different types of rails and concrete sleeper line after large and medium repair and sieving operations, and also suitable for tamping operation of ballast on newly built track bed. The equipment has superior performance, reasonable structure, safety and reliability, and high working efficiency. It fully meets the needs of railway ballast tamping operation