The working device is the main component of hydraulic excavators. The SY series excavator is equipped with a backhoe working device, which is mainly used to excavate soil below the stopping surface, but can also excavate soil below large cutting heights. In addition to digging pits, digging trenches, and loading, it can also perform simple leveling work on the site. Excavation operations are suitable for excavating soil of grades I-IV, with hydraulic hammers or blasting methods required for grades V and above. The backhoe working device consists of the boom, arm, bucket, rocker, connecting rod, and hydraulic pipelines including the boom cylinder, arm cylinder, and bucket cylinder.