4 Key Factors Influencing Viscosity Index Improver Selection
2 min read
When selecting a viscosity index (VI) improver for lubricants, various factors must be considered to ensure the lubricant performs optimally under a range of temperatures. VI improvers are designed to improve the lubricant’s ability to maintain consistent viscosity, which is important for engine efficiency and longevity. The right choice of additive can significantly impact lubricant performance and protection. A knowledgeable lubricant company can help steer these factors to ensure that the best VIIs are chosen for a given formulation.
Base oil type:
The type of base oil used in the lubricant formulation significantly impacts the choice of viscosity index improver. Mineral oils, synthetic oils, and semi-synthetic oils all have different properties, and each may require different additives to achieve the desired performance. For example, synthetic oils often have a higher viscosity index to begin with, requiring less substantial improvement from VIIs. In contrast, mineral oils may benefit from more aggressive viscosity index improving additives to ensure adequate temperature stability.
Operating temperature range:
The temperature range at which the lubricant will be used is one of the most important factors to consider. VIIs are designed to help lubricants maintain a consistent viscosity in both high and low-temperature conditions. For applications with wide temperature variations, such as in automotive engines or industrial machinery, selecting a Viscosity Index Improver that can perform in extreme heat and cold is important. The right additive ensures that the lubricant remains effective across the entire temperature range.
Additive compatibility:
Lubricants often contain multiple additives that serve different purposes, such as anti-wear agents, corrosion inhibitors, and detergents. The selection of a viscosity index improver must consider the compatibility of the VIIs with other additives in the formulation. Incompatibilities between additives can lead to issues such as instability or premature degradation of the oil. A lubricant company ensures that all additives work in harmony to increase lubricant performance and longevity.
Performance requirements:
Each application has specific performance needs that must be met, such as fuel efficiency, reduced wear, or low emissions. Depending on the performance goals, the viscosity index improver selected may vary. For example, a lubricant designed for high-performance vehicles may require a more robust viscosity index improver to achieve the desired balance between fuel economy and protection, while industrial lubricants may consider longevity and stability.
