柱塞偶件、出油阀偶件、针阀偶件是柴油机中没有互换性的三大精密偶件。柱塞与套筒、出油阀与出油阀座、针阀与针阀体的配合都有严格的要求。但在柴油机运转过程中,三大偶件会有不同程度的磨损,严重时会影响它们配合的密封性。下面简要论述三大偶件磨损后的危害及密封性能的简易检查方法。 Plunger coupling parts, oil valve coupling parts, needle coupling parts are not interchangeable in the diesel engine, the three precision couplings. Plunger and sleeve, the output valve and the valve seat, needle valve and needle with the body have strict requirements. However, during the operation of the diesel engine, the three major occasions will have different degrees of wear and tear, which may affect the tightness of their cooperation. The following briefly discusses the hazards of the three major wear parts and sealing performance of a simple inspection method.