Selecting Lubricant Formulations - Matching the Application

Scott Schwindaman, Lubrication Engineers, Inc.

As a lubricant manufacturer that produces both mineral- and synthetic-based lubricants, Lubrication Engineers, Inc. is concerned with the trend that has emerged to emphasize synthetic lubricants in many applications.

While the trend is intended to promote improved lubrication from the user’s standpoint, he or she can be misled in the idea that a synthetic-based lubricant will always provide superior performance.

To help the end user choose the right path, he or she must be informed of how the different types of lubricants are formulated with respect to performance in the application.

There are four principal types of finished lubricants produced today.

Mineral Oils, No Additives

The first and oldest is mineral oils with no additives. These oils are typically seen in the limited applications where no enhancement to the base oil is needed. Applications of this type include American Petroleum Institute (API) SA engine oil, barrier oils, seal oils, technical oils, etc.

Mineral Base Oils with Additives

The second type is mineral base oils with additives. These lubricants make up the majority of the commercially available lubricants in the marketplace today. Applications of this type of lubricant include engine oil, hydraulic oil, turbine oil, gear oil, air compressor oil, etc. These types of lubricants are applicable except in high or low temperatures or where a hostile environment is affecting the lubricant.

Synthetic Base Oils with Additives

The third type is synthetic base oils with additives. These oils make up a small part of the overall lubricant marketplace but their use is increasing due to their popularity with many lubricant end users.

For the past decade, the end user has been told in passenger car motor oil advertising campaigns that these lubricants perform better than mineral-based oils. Due to the strategic advertising directed at the general public for passenger car motor oil, most lubricant end users believe that synthetic equals superior performance over other types of lubricant, regardless of the application.

Synthetic base oils include many different types of compounds, some limited to a single specific application. These synthetic-based oils are produced by many companies including major oil companies.

Polyalphaolefin (PAO) is a primary product produced in the synthetic base oil market. In the commercial lubricant grades, the synthetic lubricant typically will provide improved overall performance when compared to the commercial mineral-based lubricant.

Enhanced Lubricants

The fourth type includes enhanced lubricants that are produced by a limited number of high-performance lubricant manufacturers that go beyond the synthetic vs. mineral oil argument to formulate a superior lubricant.

It is the philosophy of Lubrication Engineers, Inc. to formulate for superior performance in a specific range of applications without limitations to the base oil type or performance additives used. If the high-performance lubricant manufacturer believes that synthetic base oil with additives is needed for the application, then the lubricant is formulated with these guidelines.

These manufacturers know that mineral base oil with properly selected and balanced conventional and proprietary additives can be formulated with a robust treat level to provide superior application performance. Thus, the lubricant end user is given a lubricant that provides superior performance at the most economical cost for the application.

To describe the concept of formulating an enhanced lubricant that is application-specific, the strengths and weaknesses of both the mineral and synthetic base oils must be examined.

Strengths of the synthetic-based lubricants include applications where high or low temperatures are expected or a hostile environment would be detrimental to a mineral oil-based lubricant. Strengths of the mineral oil include improved additive solubility, natural oxidation resistance characteristics, better seal compatibility and lower base oil cost.

Weaknesses of the synthetic-based lubricants include: limited additive solubility, reversal of ester-based synthetic base oil to an acid, seal incompatibility with some seal materials, and a significantly higher cost per gallon compared to most mineral-based oils. Mineral-based oils have limitations in high- and low-temperature applications and certain atmospheres.

Mission of the Enhanced Lubricant Formulator

The high-performance lubricant manufacturer must inform lubricant end users that lubricants are formulated beyond the base oil, whether it is mineral or synthetic base oil. Enhanced lubricants formulated and manufactured by a high-performance lubricant manufacturer are designed to provide the highest level of performance in a specific application.

This performance is proven in both laboratory tests and actual field applications. The lubricant end user ultimately seeks improved performance in a particular application.

Enhanced lubricants are designed significantly beyond the minimal formulating done for commercial-grade mineral or synthetic base oil lubricants. When formulating these enhanced lubricants, research staff look for synergistic combinations between the base oil (synthetic or mineral), conventional additives and proprietary additives. This synergy is what allows the product to provide the maximum performance for the application.

Formulation of Enhanced Lubricants

As discussed earlier, the first step in formulating is to decide if the application needs mineral or synthetic base oil. Determine which one will provide the superior application performance.

The second step is to determine what conventional additives and what quality levels are available around which to build the core of the lubricant. While commercial-grade lubricants are formulated only to a minimal performance level, an enhanced lubricant is formulated well beyond this point.

This is accomplished by searching for synergy with high-quality component additives that enhance the performance of the lubricant. Additional additive components are then added at optimum treat levels to assure the enhanced lubricant will deliver maximum performance for the specific application.

If the formulation requires synthetic base oil, the main issue remains the additive concentration needed for superior performance.

The third and final step of formulating an enhanced lubricant is choosing which proprietary additives to use. Through basic research and field performance, high-performance lubricant manufacturers will have a number of proprietary additives that work in specific applications and have proven to enhance the performance of the lubricant. One or more of these additives will be used to fine-tune the enhanced lubricant.

The Educated End User

Once a lubricant end user understands what is involved in formulating an enhanced lubricant, it is simple to see where a synthetic lubricant might not be the superior product for the particular application. Also, the price of the enhanced lubricant is now more justified because the customer understands that there is a technology and performance level beyond that of the lubricant that has previously been used in the specific application.

In the continuing debate about synthetic versus mineral oils, the end user is interested in protecting the investment in his equipment. High-performance lubricant manufacturers can offer enhanced lubricants specifically formulated to provide optimum protection for the end user’s equipment.

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