一台东风—12型手扶拖拉机工作中转速不稳,转速自动降低,接着就熄火。检查油箱,燃油足够,油路中无空气,柴油粗细滤清器及空气滤清器未堵塞,调速器各零部件均正常,检查三大精密偶件,喷油器针阀偶件雾化良好,出油阀偶件无磨损,柱塞副头部有大小不等的麻点和蜂窝状孔群,这种现象称之为柱塞穴蚀。 柱塞的穴蚀使柱塞头部很快磨损,而且磨成不规则的棱圆形,使局部间隙增大,导致柱塞副的密封性能下降 A Dongfeng -12 walking tractor work unsteady speed, speed automatically reduced, then turn off. Check the fuel tank, enough fuel, no air in the oil line, diesel fuel filter and air filter is not blocked, the governor of all parts are normal, check the three precision coupling parts, injector needle valve atomization Good, no oil valve wear parts, plunger head head ranging from pits and honeycomb-shaped hole group, this phenomenon is called plunger pitting. Piston cavitation causes the plunger head wear quickly, and grinding into an irregular prism, the local gap increases, leading to the sealing performance of the plunger pair decreased