Basisschmierstoffs

Basisschmierstoffs, typically called base oils, are the principal component of lubricating oils and greases. They form the lubricating film that reduces friction and wear between moving parts and largely determine the oil’s flow, viscosity, and temperature behavior. Additives are blended into base oils to provide properties such as anti-wear, detergency, and antioxidation, but the base stock largely sets viscosity, volatility, and oxidative stability.

Base oils are categorized by origin and refining process. Mineral base oils are derived from crude oil and are classified by API Groups I–III, with Group I offering lower purity and higher sulfur content, and Groups II and III providing higher purity and better oxidation resistance. Synthetic base oils include polyalphaolefins (PAO, Group IV) and esters (Group V), which generally offer superior low-temperature fluidity, high-temperature stability, and reduced volatility. Other basestocks include silicone oils, polyalkylene glycols, and bio-based esters such as vegetable oils. In practice, lubricants often blend different base oils to balance performance, cost, and environmental considerations.

Key properties used to select a base oil include viscosity at operating temperature, viscosity index (temperature dependence), pour point, flash point, and oxidative stability. Compatibility with additives, seal materials, and service conditions are also critical factors.

Production and refinement: mineral base oils are produced by refining crude oil, including solvent refining and hydroprocessing. Synthetic base oils are manufactured through chemical synthesis or advanced polymerization processes. The choice of base oil influences energy efficiency, wear protection, service life, and environmental impact.