"Our client insists on 'reprocessing' his own oil. I keep emphasizing that the risk is never worth it when it comes to lube oil. Do you come across this and do you have any statistics on machine failures due to improper lubrication?"
There are many statistics on machine failures caused by improper lubrication. For instance, one bearing manufacturer claims that approximately 90 percent of all bearing failures occur due to lubrication issues. A study by the German Steel Industry Association found that 43 percent of machine failures were the result of improper lubricant selection and usage. Of course, these studies don’t necessarily address the question of whether reprocessing oil is a good idea.
Industrial lubricants can be very expensive, so the desire to get the most out of them is high. This leads to creative solutions for capturing leaking oil and reintroducing it back into the system. Some organizations take collected oil and filter it prior to putting it back into service. Although it is understandable that this practice is used to save money, the risks typically far outweigh the rewards.
Contamination is the biggest risk. If oil is captured after a leak, it is subject to a wide range of environmental contaminants, including dirt, water, processing material or heat. While filtration can remove solid contaminants and vacuum dehydration can eliminate moisture, these processes take time. When you factor in the cost of filtration, you begin to see that reprocessing lubricants can end up being more expensive in the long run.
Perhaps the client is referring to re-additizing the oil. Additives deplete over time. When they drop to an unsafe level, the lubricant normally is changed out. Reblending an additive concentrate back into a used lubricant is a tricky proposition. The results are unpredictable without considerable lab work. Also, if the base oil is damaged, no amount of additives can transform the oil to a "like new" condition.
However, there are a few scenarios when it may make sense to reprocess a lubricant, such as if gross contamination was allowed into the system or a large oil leak was captured in a collection vessel and covered as quickly as possible. In these cases, filtration could solve the problem if it is performed immediately after the contamination occurs.
Many organizations employ a bleed-and-feed strategy to limp along without performing a full oil change. This involves draining out a percentage of the oil in the reservoir and refilling it with new oil. The new oil will bring with it fresh additives that can help prolong the need for a wholesale oil change.