Treatment Measures for Mechanical Failure of Diesel Generator

Generally, before the diesel generator is damaged, its speed, sound, exhaust, water temperature, oil pressure and other aspects will show some abnormal signs, that is, the characteristics of damage omen. So operators should make accurate judgments quickly based on the characteristics of precursors and take decisive measures to prevent damage.

Symptom characteristics of overspeed damage: The speed suddenly increases and becomes faster, not controlled by the throttle, the sound is harsh, and the exhaust pipe emits a large amount of blue or black smoke. Flying cars belong to the category of overspeed idling, and they do not occur when working under load. They are only possible when the load is suddenly removed or reduced during start-up or operation.

The detailed cause is that the speed controller mechanism is damaged, causing the oil supply to lose control or excessive oil in the oil pan. If there is a warning of overspeed, if urgent steps are not taken immediately, it will eventually lead to major accidents such as cylinder knocking and shaft breakage.

Exclusion plan: The detailed method is to achieve flameout by cutting off oil or gas. The emergency measures that can be taken are: firstly, turn off the throttle to stop the oil supply and apply the brake; The second is to block the intake pipe and cut off the entry of air; Thirdly, quickly release the high-pressure oil pipe to stop supplying oil; Fourth, diesel generator used for power generation can use high-grade heavy load (braking) during traveling, which makes the diesel generator flameout due to insufficient torsional air.

Precursor characteristics of sticking cylinder failure: decreased speed, weak operation, dull sound, extremely high water temperature, with a water temperature gauge indicating over 100 ℃. At this point, spraying some water on the machine will quickly evaporate. The specific cause is severe water shortage and the failure of the water cooling mechanism. If the engine is immediately shut down, it may cause cylinder sticking. Treatment measures: Idle for a period of time or turn the spindle to help cool down, so that the water temperature drops to around 40 ℃, and then slowly add water to the water tank. Be careful not to add water immediately, otherwise it may cause deformation or cracking of the parts due to a sudden and rapid drop in local temperature.

Precursor characteristics of cylinder damage by knocking: There is a clicking sound in the oil pan, similar to the sound of a small hammer lightly tapping on a hard floor, commonly known as the cylinder knocking sound. The oil pressure drops, which is more pronounced during sudden loading.  

Knocking the cylinder is a highly destructive mechanical failure, mainly caused by the loosening or stretching of the connecting rod bolts, excessive clearance between the connecting rod shaft, and the loosening or breaking of the bolts. If there is a knocking sound, but the oil pressure is normal, it is not a precursor to knocking the cylinder, and consideration should be given to adjusting the fuel supply advance angle.

Warning features of burnt tile damage: The sound is muffled, as if the load suddenly increases and the speed decreases, the oil pressure drops, and black smoke is emitted from smoke exhaust. Burning the bearing pad can cause the bearing pad and journal to lock and stall, specifically due to the damage of the lubricating oil film on the surface of the bearing pad, direct contact with the metal on the surface of the bearing pad and journal, rapid increase in friction temperature, and surface adhesion. 

Pre warning characteristics of shaft failure: A dull knocking sound is generated in the oil pan, and when the throttle is triggered, the knocking sound becomes louder. When idling, the parts shake severely, and the exhaust emits black smoke. Broken shafts are caused by mechanical fatigue at the shoulder of the main journal, and there is a gradual process from cracking to fracture. When implicit fission occurs, the precursor characteristics are not obvious. As the crack expands, the precursor characteristics become more and more obvious, ultimately leading to shaft failure and flameout. If the throttle or other vibrations occur or the knocking frequency matches, the machine may be at the critical point of shaft breakage. At this point, the cover is removed for inspection and the flywheel is pushed by hand. If the axial clearance is large and the push is effortless, it indicates that the main shaft has been broken.

The above is the content recommended by Dingbo Power for you to simply explain the generation and elimination steps of mechanical faults of diesel generator. If you still don't understand this, please come to Dingbo Power website, we will answer for you. Or if you have purchasing plan of diesel generator, welcome to contact us by email dingbo@dieselgeneratortech.com or call us phone +8613481024441.