If your circulating oil should not to be changed within a certain period time or running hours and you want to monitor its condition, so following oil sampling crib is bound to be useful.
The parameters monitored for hydraulic oils should be system cleanliness, oil condition and system wear. System cleanliness provides an indication of the overall rate of ingress of contaminants and the effectiveness of the in-line filtering equipment. With this in mind, the location of the sampling point is not as important as the consistent use of the same sampling point for all sampling. Generally, the most convenient location is in the system return line, where relatively small pressure allows safe sampling.
Normally, manufacturers create their own designated sampling point. If it is an oil circulating system (CPP hydraulic oil system) type the sampling location may be in return line, at the filter inlet. But in case of non-circulating system (Mooring winch gear box oil) representative sampling is almost impossible. In such cases sampling from the expansion/sump tank is suffusion.For best sampling results ensure:
- Sample point is not exposed to dusty or moist conditions;
- Run an equipment for a short time, ensure oil flow and temperatures are steady and stable;
- Sample point is clean;
- Sampling equipment is thoroughly cleaned;
- Flush through at least one litre of oil before sampling commences;
- Open sampling bottle just before sampling is about to commence;
- Seal sample bottle immediately after filling;
- Label oil sample accordingly.
- For gear boxes fitted with lubrication oil circulation pumps, the sample should be taken at the pump discharge, before filters;
- For splash lubricated gearboxes, the sample may be drawn from the bottom of the sump by means of a sampling pump from convenient drain plug as low down in the sump as possible. Sampling should be attempted when machinery is stopped. Install permanent sampling point instead of plug, where possible. Always sample immediately after stopping the gearboxes to ensure that contaminants and wear particles do not have time to settle out.