天然气发动机低速小负荷机油消耗量控制技术的研究

分析表明,导致天然气发动机低速小负荷机油消耗量过高的主要原因是:随着发动机转速和负荷减小,节气门开度减小,造成进气冲程时气缸内压力为负压,使机油被吸入到气缸内而造成机油消耗量过高。提出了活塞环结构改进方案和怠速机油消耗量测量方法。试验结果表明,通过改进活塞环结构,发动机的怠速机油消耗量降低了33.1%,且顺利通过了500h可靠性试验。

Investigation on Control of Lubricant Consumption at Lower Speed and Smaller Load Condition in a CNG Engine

This paper analyzed the problem that lubricant consumption at lower speed and smaller load condition in a CNG engine is too high.The analysis revealed that as engine speed and load reduce,the opening of throttle valve reduces,cylinder pressure at intake stroke is lower than atmospheric pressure gradually,lubricant is sucked into cylinder,which leads to exorbitant lubricant consumption.The structures of piston rings were improved and the test method of lubricant consumption at idle condition was proposed.Test results showed that the lubricant consumption at idle condition was reduced by 33.1 % after piston rings were improved.The problem of exorbitant lubricant consumption at lower speed and smaller load condition was solved.The CNG engine equipped improved piston rings passed through 500 hours durability test smoothly.