The crankshaft function, structure and wear test

1, what is the role of the crankshaft? The piston connecting rod set of gas pressure coming into torque and external output, and drives the engine's distribution agencies and other auxiliary equipment. 2, 1 chart 3, the crankshaft crankshaft crankshaft structure tutu common wear? What are those? Common loss are: crankshaft bending deformation, cracks and uneven wear ( The most common) Three conditions. 1) The cause of the bending deformation of a and engine work in the deflagration and overload conditions. Don't work or two [b, individual cylinder Imbalance. C, when installation, main bearing looseness. 2) Crack crack even the reason of fracture is caused by the stress concentration. Figure 2 crankshaft are most likely to damage area 3) Uneven wear of uneven wear of the crankshaft is one of the most common loss, prone position: main journal and the connecting rod journal ( As is shown in figure 3) 。 Figure 3 crankshaft main journal and journal 4 connecting rod, crankshaft wear testing: outside micrometer. Test objective: to measure the diameter of the shaft neck ( Calculate roundness and cylindricity error) 。 A, roundness error: the same cross section diameter and minimum diameter difference of the half. B, cylindricity error: the same cylinder, not in the same section, maximum diameter and minimum diameter difference of the half. 5, wear characteristics of a crankshaft, wear mainly occurred in the crankshaft main journal and the part of the connecting rod journal, and the wear is uneven. B, main shaft neck of maximum wear near left-edge connecting rod shaft, connecting rod journal's biggest worn parts at the side of the main journal. C, connecting rod journal wear over main journal, Load, lubrication) 。