When manufacturing plants receive raw materials on their dock, there is usually a rigorous quality control process in place to check these materials before they are sent to the production lines. Companies pay good money for these materials, and they expect them to be in good condition in order to ensure there are no manufacturing flaws in the end product. Do lubricants at your site receive the same amount of attention when they are received? With the price of lubricants being so high and the expectation for them to perform (often under extreme circumstances), shouldn’t they have a quality control process of their own? Just like faulty raw materials create flawed products, less than ideal lubricants can increase the chance of machine failure.
Creating a Quality Control Process
The first step when starting a Quality Control Process is to list out the goals of the program: what are you trying to accomplish, and what tests are you going to use to verify success? Is the program going to go as far as performing in-depth oil analysis on incoming lubricants, or are you just going to physically inspect the deliveries?
Typical steps in a Quality Control Process
Receiving Times - Make sure all lubricants are received in the agreed-upon amount of time. This step doesn’t check the quality of the lubricants themselves but instead shows the quality of the supplier. If a single delivery is a bit late, it can probably be excused; but if deliveries are consistently late, you might think about switching suppliers.
Accompanying Documents - When setting up an original agreement with the lubricant supplier, some companies request that a Quality Certificate or Certificate of Analysis be brought when lubricants are delivered. This document includes details such as when a sample was pulled, the analysis of the additives and the particle count. Other documents, such as a record of the last time the blending plant or supplier was audited, might also be requested.
Visual Inspection - Ensure the correct lubricant is being delivered in the right container/size. Check the container’s bungs, caps or seals to make sure there are no points for possible contamination. Check the label to make sure the correct lubricant is being received, that the lubricant is not out of date, and that it falls in line with the shelf life of the Q.C. program. If bulk lubricants are being delivered and offloaded via a pump, all lubricant transfer equipment should be inspected to ensure that it was properly stored and to make sure you will not be introducing contaminants into the lubricant. All transfer equipment should also be flushed before they deliver lubricants to the bulk tank. Bulk deliveries should always have a sample taken to confirm properties with lab testing.
Oil Analysis - Depending on the volume of lubricants and overall machine criticality, a site may want to perform oil analysis on all incoming lubricants. Testing may be done on-site or sent to a laboratory for more in-depth testing. A couple of on-site tests that can be performed are:
- Viscosity - An easy test that can be done on-site with a relatively inexpensive tool called a visgauge. Viscosity is the single most important property of a lubricant; if the delivered lubricant is not the correct viscosity, it should be returned.
- Particle Count - On-site particle counters are becoming a common tool for lubrication programs these days. Within a couple of minutes, you can get a report on how clean or dirty the tested lubricant is. Remember, just because the oil is new doesn’t mean the oil is clean.
What to do with lubricants that fail
Listing actions that should be taken when lubricants fail any of the tests you put them through is important to close the circle of the quality process. These steps should be created in collaboration with your vendor and should be clearly defined based on the test that the lubricant failed. Commonly, once a lubricant is rejected, we should receive a replacement lubricant within a specified timeframe to help avoid using the failed product.
