Page 354 - Handbook of Materials Failure Analysis

(a) 200µm (b) 100µm

200µm 200µm
(c) (d)
FIGURE 13.67
The microorganism debris from the used oil samples: (a) a microorganism debris from a
gearbox oil sample (200 ); (b) a microorganism debris from a bearing oil sample (200 );
(c) a microorganism debris from geothermal steam turbine oil sample (100 );
(d) a microorganism debris from a hydro-turbine oil sample (200 ).

Table 13.1 Summary of the Case Studies
Failure Mode and the
Case Machine Root Cause of the
Studies Type Failure Typical Wear Particles
1 Race car Catastrophic wear due Large-size wear particles with
gearbox to inadequate color oxide film
lubrication (wrong type
of oil)
2 Wind Bearing spalling by the Large-size wear particles
Turbine white etching cracks (laminar particle, sliding wear
gearbox (WEC) particles, fatigue wear particle,
and spherical particle)
3 Bulldozer Seizure failure by Large-size sliding wear
diesel catastrophic wear due particles, fatigue wear
engine to inadequate particles, and copper alloy
lubrication wear particles
4 Yankee Bearing failure due to Large-size fatigue wear
machine in high level of moisture particles with multi-oxide
a paper mill content in the oil scales
5 250 Kw Impending catastrophic Large-size sliding wear
gearbox in wear due to the particles and black oxide
a paper mill blockage of the oil fatigue wear particles
supply
6 55 Mw gas The onset severe wear Vanish particles, babbit alloy
turbine on babbit bearing pad wear particles, and sliding
load due to varnish deposit wear particles with blue oxide
gearbox color