GB/Z 19848-2005 is a guide on the control of the cleanliness of hydraulic components. It guides how to achieve and control the cleanliness of the whole process from the manufacture of hydraulic components to the installation. For the manufacturing process, give processing and cleaning process suggestions, and standardize the cleaning requirements of raw materials and production environment. In the transportation and storage stage, explain protective measures to avoid secondary pollution. In the installation process, clarify the cleaning standards of the installation site and tools and the installation operation specifications. Following this guide can effectively improve the cleanliness of hydraulic components, reduce system failures, ensure the efficient and stable operation of the hydraulic system, and prolong the service life of the equipment.