YD-22III Auto Hydraulic Rail Tamping Machine YD-22III Auto hydraulic tamping machine is an updated product based on the experience of domestic and foreign users on the tamping machine , using new materials and new technologies. This machine is suitable for the tamping operation after the large-scale and middle-repair cleaning operations of different types of rails and concrete sleeper lines ; it is also suitable for the tamping operation of the ballast on the newly-built line . The automatic hydraulic running function is added which can realize non-human Push forward or backward . The machine has superior performance , reasonable structure safety and reliability , and high operating efficiency , which fully meets the needs of railway ballast tamping operations