GB/T 21938-2021
ActiveEarth-moving machinery─Hydraulic excavator and backhoe loader lowering control device─Requirements and tests
土方机械 液压挖掘机和挖掘装载机下降控制装置 要求和试验
Application Summary AI generated
This standard specifies performance requirements and test methods for lowering control devices on hydraulic excavators and backhoe loaders, ensuring safe and controlled descent of the work equipment. It is applied in the design, manufacturing, and type-testing of earth-moving machinery to prevent uncontrolled or hazardous lowering of attachments. The standard is relevant for construction, mining, and infrastructure industries where these machines operate.
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Transparency note: The application summary and key sentences on this page were automatically generated by AI from the standard's original text. This content has not been human-verified and should not be used for compliance or regulatory purposes. Always refer to the official standard document from the issuing authority.