Treatment measures for five kinds of mechanical faults

Mechanical faults occur in the operation of the diesel engine, while light causes the damage of the basic parts, which results in serious mechanical accidents. Normally, before the diesel engine breaks down, its speed, sound, exhaust, water temperature, oil pressure and so on will show some abnormal signs, that is, fault omen characteristics. Therefore, operators should be based on the characteristics of the warning quickly to make the correct judgment, decisive measures taken to avoid accidents.

A, "speed" failure. The signs: speed suddenly increased, and more and more quickly, without throttle control, abnormal noise, harsh, exhaust smoke a lot of smoke or black smoke.

(1) the "speed car" belongs to the overspeed idling, and the work will not happen under the load, only when the load is suddenly removed or relieved at the beginning or at work. The main reason is the failure of the governor system, causing the loss of oil supply or excessive oil in the sump. A "coaster" warning, if not immediately taken emergency measures, will eventually lead to tamping cylinder, broken shaft and other major accidents.

The treatment measures: mainly through broken oil or gas to reach out. Emergency measures can be taken: one off the throttle to stop the oil and depress the brake; two is the blockage of the intake pipe, cut off the air; the three is the rapid release of high pressure tubing to stop the oil; four car diesel engine available in high-end walking heavy load (brake), the engine flameout due to twist the gas shortage.

Two, cylinder fault.

The signs: the speed drops, operation weakness, voice, high water temperature, with temperature meter indicating more than 100 DEG C. At this point, sprinkle some water on the machine, it will evaporate quickly. The main reason is the severe water shortage and the water cooling system is invalid. If the flame is stopped immediately, the cylinder may be stuck.

The treatment measures: idle for a period of time or to help cool the flameout crank crankshaft, the temperature dropped to 40 degrees Celsius, then slowly add cooling water. Be careful not to add cooling water immediately, or it will cause the machine to deform or crack when the local temperature suddenly drops too fast.

Three, incompletely cylinder fault.

The omen characteristic: blah sound crankcase parts, like a small hammer tapping hard floor sound, commonly known as the "knock" oil pressure drop, acceleration is more obvious. Tamping cylinder is a destructive mechanical fault, mainly due to the looseness of the connecting rod bolt or the necking of the bolt stretching, and the clearance between the connecting rod and the shaft is too large, resulting in looseness or fracture of the bolt. If there is knock cylinder sound, but the oil pressure is normal, it is not a warning cylinder, should adjust oil supply advance angle to consider.

The measures: downtime immediately replaced with new parts.

Four, burn tile fault.

The signs: sound muffled, as if the load suddenly increased to reduce speed, oil pressure drop, black smoke exhaust. The tile burning will lead to bearing and shaft neck lock and turn off, the main reason is that the bearing surface of the lubricating oil film is damaged, bearing and shaft neck, direct contact with the metal surface friction temperature rise rapidly, surface bonding caused by.

The treatment measures: immediately stop the demolition of the lid to check, connecting rod bearing, identify the cause, repair and replacement.

Five 、 shaft broken fault.

The sign features: the crankcase dull percussion sound, a sound of percussion throttle becomes large, idle running parts of the severe wobble, black smoke exhaust. The broken shaft is caused by mechanical fatigue at the shoulder of the crankshaft neck, and there is a gradual process from crack to break. When recessive fission occurs, the characteristics of omen are not obvious. With the crack enlargement, the characteristics of omen are more and more obvious, and finally the shaft break is stopped. If the throttle or other jitter or strike frequency coincide with the downtime, may be at the critical point of the broken shaft. At this time, check the cover, push the flywheel by hand, such as the axial gap is larger, and push no effort, indicating that the crankshaft has broken.

The treatment measures: warning immediately stop check, found that the crack should be replacedcrankshaft.