The common injury (Dieselpartsworld) 2016-02-28    

The common injury
Bending or twisting deformation of shaft neck surface strain, the ablation of the crankshaft, crack and even fracture.
Wear of crankshaft
Wear 1, the shaft neck and shaft connecting rod carotid radial oval and maximum wear parts corresponding to each other, namely the main journal the maximum wear next to the connecting rod shaft neck side; and connecting rod shaft neck of the maximum wear is also close to spindle neck side.
2, practice shows that the wear of the crankpin than the main shaft neck wear. This is due to the crankpin load, lubrication condition and difference.
3, connecting rod shaft neck wear inside, causing the oval.
The crankshaft crack and breaking rules
1, location: fillet crack occurred in most of the crankshaft between the crank arm and axle, and the oil hole. The former is more serious when the transverse crack, causing fracture, should focus on checking. The latter is to develop along the axial axial crack, oblique oil hole edge.
2, why:
(1) the transverse and axial cracks are mainly caused by the stress concentration.
(2) the crack shaft hole of the oil, mainly because the oil oblique oil hole, the stress distribution is asymmetric.