Parker FG-K17401-KW, Instruction Manual

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MA-K17510-KW LinerSCAN manual ISSUE P.doc Page 64 of 93
6.6 Effect of Maintenance
Inspecting cylinders through the scavenge port is the recommended way to spot problems like scuffing
and should be carried out on a regular basis in conformance with the manufacturers guidelines. Other
maintenance events on the cylinders have on multiple occasions caused sudden and severe wear
events. This is usually an unavoidable consequence but it has proved useful for operators to know
when this has happened to try to limit the damage when the same operation needs to be carried out
again.
An example of such an event was seen when a scheduled 6 monthly inspection of two of the cylinders
was carried out. Cylinders 1 and 5 had their exhaust valves lifted and bore measurements were taken.
Results showed both were in good condition and had low wear rates.
During the next short voyage after maintenance, all cylinders except 1 and 5 had normal iron readings
of approximately 100ppm or less. Wear levels for the inspected cylinders rapidly increased to over
4000ppm.
The first 12 hours of wear equated to more than one month’s normal wear! Such a phenomenon had
never previously been seen in real time, and it was unknown if permanent damage had taken place.
Wear levels began dropping after about three and a half hours.
Figure 8 Damaged caused by routine maintenance 1
This showed that although the maintenance had caused some damage to the cylinder it did recover
and showed what looked like a bedding in curve. Oil samples were taken during this voyage and the
sensor results were found to correlate well with ICP, XRF and PQ.