Four types of damage to crankshafts
2020-01-02
After the engine is used for a long time, the crankshaft may be damaged due to many reasons. In addition to the crankshaft itself, there are other abnormal damages, such as scratches on the surface of the journal and deformation of the crankshaft.
1.The gap between crankshaft journal and bearing bush increases after wear
When the crankshaft rotates, under the action of centrifugal force, the mechanical impurities in the oil are inclined to one side of the oil hole and become abrasive, which causes the journal to wear unevenly and produces taper.
2.Scratch or pull on surface of crankshaft journal
The lubricating oil of oil sump is not changed on time, so that the lubricating oil contains large metal and other abrasive particles mixed into the gap of bearing shell and journal to mark and tear the friction surface.
Air filter maintenance is not in place, cylinder liner, piston and piston ring wear gap increases, with sand, impurities and other abrasives with air inhalation cylinder combustion after running into the oil sump, circulation into the journal and bearing clearance.
3.The crankshaft deformation
Crankshaft deformation is usually bending deformation and torsional deformation, too much deformation of the crankshaft will lead to its own and connected parts of the wear, accelerated fatigue, crankshaft fracture and excessive mechanical vibration.
4.Crankshaft fracture
All causes of crankshaft journal surface crack and crankshaft bending and distortion are the causes of crankshaft fracture.
