Gear failures

When lifting the load, it must be kept as close to the floor as practicable to prevent harm in case of gear failure. All equipment must be fully checked and replaced if damaged. 

BAYDAR, N. BALL, A. (2003) Detection of gear failures via vibration and acoustic signals using wavelet transform. Mechanical Systems and Signal Processing, 17 (4), pp. 787-804. 

Alban, L. E. Systematic Analysis of Gear Failures. Metals Park, OH ASM International, 1985. 

One of the primary causes of gear failure is the fact that, with few exceptions, gear sets are designed for operation in one direction only. Failure is often caused by inappropriate bidirectional operation of the gearbox or backward installation of the gear set. Unless specifically manufactured for bidirectional operation, the nonpower side of the gear s teeth is not finished. Therefore, this side is tougher and does not provide the same tolerance as the finished power side. 

Table 2. Modelling of spur gear failures by variation of spring and damping coefficients, [c] = Nmlrad, [d = Nmsl rad...

In this mixed film lubrication model it s considered that the load share function depends not only on A but also on gear pitch line velocity Vt, and the values of K in f(A) are determined firom the gear failure probability curves from Wellauer and Holloway, presented in figure 6 [9]. 

These curves, based on experimental gear failure results, establish the specific lubricant film thickness A) for which the probability of tooth contact failure is 5% and 80%, as a function of the gear pitch line velocity. 

Figure 6. Gear failure probability curves (5% and 80%) from Wellauer e Holloway [9].

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