自卸车液压系统总成和部件的可靠性,与所采用的工作液的清洁程度有关。使用经验和研究的结果都表明,尽管自卸车液压系统中有滤清器过滤工作液,但其中仍含有0.06～0.11％的杂质。每毫升液压系统的工作液中,都含有几万个具有很高硬度和磨料作用的机械杂质,随同液体一起循环。这些杂质的尺寸,有的与液压系统部件的最小配合间隙值相近, The reliability of the hydraulic system assembly and components of the dump truck is related to the level of cleanliness of the working fluid used. Experiences and research results show that, although the filter hydraulic system working fluid filter, but it still contains 0.06 to 0.11% of the impurities. Every milliliter of hydraulic system working fluid, contains tens of thousands of mechanical impurities with high hardness and abrasive action, along with the liquid circulation. The size of these impurities, and some with hydraulic system components with the minimum gap size close,