Lubricant cleanliness is a huge factor in your plant machinery’s reliability, durability, and efficiency. Microscopic particle contaminants in the lubricant can bring production to a grinding halt, incurring costly downtime, repairs, or even equipment replacement. Yet identifying and maintaining the right fluid cleanliness levels across vast manufacturing operations with multiple production facilities and thousands of moving parts is daunting, if not overwhelming. Where do you begin?

Realistically, some level of particulate matter is bound to be present in your lubricant. Hence the reason why filters in equipment exist – to manage contamination. Thus, the objective is not to try and “purify” the fluid of all contaminants, but to determine the required cleanliness level (RCL) for your applications, expressed in the International Standards Organization (ISO) code, and then make sure the new oil you are using meets that code. 

In an earlier Lube Matters article, we discussed a variety of methods for determining optimal cleanliness, briefly referencing the ISO 12669 standard. ISO 12669 warrants a deeper explanation. It is widely regarded as a highly effective RCL calculation methodology, one that can greatly simplify the process of ensuring oil cleanliness across a broad cross section of equipment in your operation, or for a single piece of equipment that poses unique lubrication challenges.

Let’s say your facility has 2,000 pieces of equipment, some with multiple components, all requiring lubrication. It is not practical to look up the OEM cleanliness specs for each piece of machinery, nor is it economically or operationally feasible to purchase, store, and apply a different cleanliness level for all your equipment. Your goal is to streamline and standardize lubrication management as much as possible to keep expenses down. To do that, conduct a criticality assessment to identify your most critical assets. You probably know off the top of your head the ones that could significantly impair your production if they were compromised. Using the ISO 12669 calculation methodology helps identify the optimal RCL specification within that group of equipment, and then be sure to use that specification across all your equipment. Equipment was never harmed by the lubricant being too clean (that is unless filtration was too aggressive and stripped out critical additives).

In the other case, let’s say you have a single piece of equipment that is an outlier – it’s old, it’s been retrofitted, perhaps it’s no longer even made or sold. Replacing it is not an option and you have to try to extend its life, which includes minimizing wear from contamination. There is no OEM spec to refer to and that means you have to come up with your own. In this case, ISO 12669 simplifies the process of arriving at an RCL with which you can be comfortable and confident in utilizing.

How it Works

To arrive at the RCL for your most critical assets using the ISO 12669 methodology, start by assigning weights to six factors affecting your equipment’s lubricant cleanliness requirements:

Duty Cycle and Working Pressure: On a scale of 1 to 8, rate the variations in working pressure under which the equipment performs, with 1 representing the lowest and most consistent pressure, and 8 the highest pressure and widest variations. 

Component Contaminant Sensitivity: On a scale of 1 to 8, how sensitive is the equipment to contamination? Less sensitive equipment like ram pumps might have the lowest or 1 weight, while high-performance servo valves might warrant an 8 or the highest sensitivity weight.

System Life Expectancy: Assign a weight based on remaining life expectancy on a scale from zero (1,000 hours or less) to 5 (greater than 40,000 hours). The longer the system is expected to remain in service, the more critical it is to minimize contamination.

Replacement Cost: If the equipment had to be replaced, rate the level of cost from low (1) to very high (4).

Cost of Downtime: Identify the financial impact of downtime based on how critical the asset is to your production, on a scale of 1 (low criticality/impact) to 4 (highest criticality/impact).

Risk: On a scale of 1 to 6, how likely is the equipment’s failure to cause a safety hazard or injury?

Once you have weighted all these factors, add up the individual weights to arrive at a total RCL factor. You can then correlate this number to a specific ISO code, using a table developed by the ISO. In the example shown in the adjoining table, if the total weight of your operating factors is 19, the corresponding ISO cleanliness code is 15/13/10. That is the required cleanliness level.

Now you know the cleanliness levels you need to meet. So, how do you meet them? On-site filtration is time consuming, a delicate process, and can be expensive. Which is why Chevron created the ISOCLEAN® Certified Lubricant program, where your lubricant can be delivered certified to the RCL Level every time. “Starting clean” will save you from a lot of headaches in trying to maintain your lubricant cleanliness over time.

When is the last time you took a sample from the new oil delivered to your location? Are you confident that it meets the ISO spec you have identified? If you’re unsure, it’s never been easier to find out. Right now, Chevron is offering a free new oil analysis kit. Use it to pull a sample from your new lubricant tank, send it to POLARIS Laboratories, and we’ll run a cleanliness check at no cost or obligation to buy from us. Also, feel free to contact us with questions about how to use ISO 12669 in your operation. As always, we’re here to help. 

*An earlier version of this article mistakenly referred to the ISO number as 12699.