柴油机气门导管密封结构的设计、计算和试验研究

针对柴油机气门导管的磨损和漏油问题，设计了三种不同形式的气门导管密封结构，从理论上对这三种结构所遵循的流体动力特性分别加以分析和计算，并对这些结构的漏油量进行了部件试验和整机试验。结果表明：这三种结构的实际漏油量和理论计算的漏油量相当，因此对气门导管的流体特性分析计算方法是合理的，能为结构设计提供指导；气门导管只加工凹槽而不安装密封圈的结构既起密封作用又起润滑作用，它不仅能减少进入进、排气道的机油量，而且还减轻了气门副的磨损，是简单而实用的新型密封结构。

Design, Calculation and Test for Engine Valve Guide Sealing Structures

To improve the wear resistance and decrease the oil-leakage of the diesel engine valve guide, three different sealing structures of valve guide were designed. Theoretical analysis and calculation of the characteristic of hydrodynamic lubrication for these structures were conducted respectively. And comparative tests of component oil-leakage and engine emission for these three sealing structures were also carried out. Test results were agreement with the calculation, which proves that the methods of analysis and calculation for the characteristic of hydrodynamic lubrication of engine valve guide are suitable and can provide theoretical guidance for structure designs. It also proves that the structure in which a machined sealing groove exists but no seal-ring is installed not only plays a role of sealing, but also plays a role of lubricating, which decreases the wear of valve stem and valve guide, reduces the lubricant that flows into the inlet and exhaust pipe, and improves its reliability. Meanwhile, it can lower the engine emission. So it is a simple, novel and applicable structure.