焦化发电机组发动机突然加速时会发出沉重而有力的“刚、刚、刚”的金属敲击声，严重时机体发生很大振动。这实际上是发电机组曲轴主轴承响，要如何诊断呢？

When the engine of the coking generator unit suddenly accelerates, it will make a heavy and powerful metal knocking sound of "rigid, rigid, rigid", and the engine body will vibrate greatly in serious cases. This is actually the main bearing of the crankshaft of the generator set. How to diagnose it?

原因

reason

(1)主轴承盖固定螺钉松动；(2)主轴承减磨合金烧毁或脱落；(3)主轴承和轴颈磨损过甚、轴向止推装置磨损过甚，造成径向和轴向间隙过大；(4)曲轴弯曲；(5)机油压力太低或机油变质。

(1) The fixing screws of the main bearing cap are loose; (2) The wear reducing alloy of the main bearing is burnt or falls off; (3) Excessive wear of main bearing and journal and axial thrust device, resulting in excessive radial and axial clearance; (4) Crankshaft bending; (5) The oil pressure is too low or the oil is deteriorated.

诊断方法

diagnostic method 

(1)仔细倾听。如响声是随着发动机转速的升高而增大，抖动节气门时在加油的瞬间响声较明显，这一般是主轴承松旷；如发动机在怠速或低速运转时响声较明显，高速时显得杂乱，则可能是曲轴弯曲；如在高速时机体有较大振动，机油压力显着降低，则一般是主轴承松旷严重、烧毁或减磨合金脱落。

(1) Listen carefully. For example, the noise increases with the increase of engine speed. When the throttle valve is shaken, the noise is obvious at the moment of refueling, which is generally the main bearing is loose; If the noise is obvious when the engine is running at idle speed or low speed, and it appears disorderly at high speed, the crankshaft may be bent; If the engine body vibrates greatly at high speed and the oil pressure decreases significantly, the main bearing is generally loose, burnt or the anti-wear alloy falls off.

(2)从加机油口处听诊。打开加机油口盖，从加油处仔细倾听，同时反复变更发动机转速进行试验。如果是主轴承响，可明显听到沉重有力的金属敲击声。

(2) Auscultate from the oil filling port. Open the oil filler cap, listen carefully from the oil filler, and change the engine speed repeatedly for test. If the main bearing rings, you can obviously hear the heavy and powerful metal knocking.

(3)用听诊器具听诊。将听诊器或自制的简易听诊杆，在节气门开度不断变换的同时，触在机体曲轴箱两侧与曲轴轴线齐平的位置上进行听诊，响声强的部位即为发响的主轴承。

(3) Auscultation with stethoscope. Touch the stethoscope or self-made simple stethoscope rod at the positions of both sides of the crankcase of the engine body flush with the crankshaft axis for stethoscope while the throttle opening is constantly changing. The position with strong sound is the main bearing.

(4)断火试验。松开高压油管接头，如1缸断火后响声明显减弱，则为道主轴承响；如末缸断火后响声明显减弱，则为后一道主轴承响；如任意相邻两缸同时断火响声明显减弱，则为两缸之间的主轴承响。曲轴轴向窜动所产生的响声，单缸断火无变化。

(4) Fire break test. Loosen the high-pressure oil pipe joint. If the noise is obviously reduced after cylinder 1 is disconnected, it is the first main bearing; If the sound of the last cylinder is obviously reduced after the fire is cut off, it is the sound of the last main bearing; If the sound of any two adjacent cylinders breaking fire at the same time is significantly reduced, it is the main bearing sound between the two cylinders. The sound generated by the axial movement of the crankshaft does not change when the single cylinder is cut off.

(5)踩离合器踏板试验。踩下离合器踏板保持不动，如果响声减弱或消失，则为曲轴轴向窜动产生的响声。

(5) Step on the clutch pedal for test. Press the clutch pedal and keep it still. If the noise is reduced or disappears, it is the noise caused by the axial movement of the crankshaft.

(6)焦化机的降速试验。诊断焦化机主轴承响时，为避开着火敲击声的干扰，可采取加大供油拉杆行程后再迅速收回的方法，趁发动机降速之机，如听到坚实而沉重的“刚、刚、刚”声，则有可能为主轴承响。同时应打开加机油口盖，辅之于听诊法和气缸断油法，以便于确诊。

(6) Speed reduction test of coking machine. When diagnosing the main bearing sound of the coking machine, in order to avoid the interference of the fire knocking sound, the method of increasing the stroke of the oil supply rod and then quickly retracting can be adopted. If the sound of "hard, hard, hard" is heard while the engine is slowing down, it may be the main bearing sound. At the same time, the oil filler cap should be opened, assisted by auscultation and cylinder oil cut-off method, so as to facilitate diagnosis.

焦化发电机组曲轴主轴承响怎么诊断？以上我们从五个方面来具体讲解了问题内容，您可以作为参考使用，更多问题就来我们网站http://www.huannengpower.com咨询吧。

How to diagnose the crankshaft main bearing noise of coking generator set? We have explained the content of the question from five aspects above. You can use it as a reference. For more questions, please visit our website http://www.huannengpower.com Consult.