Compressor Lubrication
Compressor Oil Plays Critical Role in Protecting Internal Metal Parts, Preventing Corrosion and Wear, and Sealing Compression Chambers
Compressor oil requirements vary considerably based on compressor type, the environment in which it is used, and the type of gas that is being compressed. Air compressors, natural gas compressors, hydrocarbon gas compressors, and refrigeration compressors each present distinct lubrication challenges. Therefore, it is imperative that you use a high-quality oil suitable for the application and environment, while also matching the ISO grade to the OEM spec.
We can help with this by recommending lubrication reliability best practices — including the right oil — for most compressor types. Royal Purple Industrial formulates lubricants using four exclusive additive technologies: Synerlec®, Synslide™, DynaGlyde™ and Purolec™. Whether you are compressing air, natural gas, ethylene, propane, ammonia, or other process gases, we have years of documented success helping our customers maximize uptime while reducing costs.
Qualities of High-Performance Oil for Use in Compressors
- Premium oil with high film strength to protect compressor internals under continuous duty cycles
- Nonfoaming in use to prevent air entrainment, which can compromise compression efficiency and accelerate oil degradation
- Filterable without additive depletion to maintain oil cleanliness throughout extended drain intervals
- Excellent solvency to minimize carbon deposits, varnish, and lacquer on discharge valves, pistons, and oil passages
- Energy efficient formulation to reduce power consumption and lower operating costs across the compressor fleet
- High viscosity index to maintain proper sealing and lubrication from cold starts through peak discharge temperatures
- Rust- and corrosion-resistant formulation to protect valves, cylinders, and internal components from moisture damage
- Demulsibility properties to rapidly shed water, keeping the oil clean and preventing emulsion-related deposit buildup
- Resistance to gas dilution from hydrocarbon and process gases, preserving oil viscosity and load-carrying ability
Reliability Solutions
After selecting your compressor oil, the next step is to put the other lubrication reliability pieces in place. First, add oil analysis to begin predictive trending of the oil and asset condition. Second, use filtration to keep the oil clean and dry. With these solutions, you can safely extend the life of the asset and the oil, which will in turn save you time and money.
Identify Suffering Points
Move Forward with Our Proven Solutions
Problem
Oil life is reduced by half for every 10°C (18°F) in temperature increase. That is why a strong antioxidant package is essential in a compressor oil. As oil oxidizes, its viscosity increases, varnish forms, sludge and sediments begin to plug filters, acid increases, and rust and corrosion take hold on internal surfaces. Rotary screw compressors, which maintain sustained high discharge temperatures, are especially vulnerable to accelerated oxidation. The consequences are clear — shortened oil life, increased maintenance frequency, and premature compressor failure.
Solution
Our high-performance compressor oils are designed to combat the effects of high temperatures, water, contaminants, and heavy loads. Synfilm® is our best-selling industrial lubricant for air compressors, pumps, and general plant equipment; offering a clean, dry, long-life formulation with outstanding oxidation stability. For environments with reservoir temperatures exceeding 200°F, Synfilm® GT delivers extreme oxidation stability along with very low-temperature fluidity. These long-lasting oils are nonfoaming and offer superior resistance to heat, oxidation, and moisture. As a result of their premium formulations, our compressor oils outperform conventional alternatives. In addition, many exceed OEM requirements. When varnish and sludge have already accumulated, Clean & Flush™ safely removes deposits while the compressor remains in service.
Problem
In reciprocating compressors, carbon deposits on discharge valves are among the most persistent and costly maintenance problems. As conventional oils break down under heat and pressure, they leave behind hard carbon residues that accumulate on valve plates, piston rings, and cylinder walls. These deposits prevent valves from sealing properly, reduce compression efficiency, increase discharge temperatures, and in severe cases can lead to compressor fires. The cycle is self-reinforcing because higher temperatures produce more deposits, which raise temperatures further and accelerate oil breakdown.
Solution
Synfilm® Recip is specifically engineered for reciprocating air compressors, delivering high film strength and energy efficiency while virtually eliminating carbon buildup on discharge valves. Its excellent solvency keeps valve plates, piston rings, and cylinders clean, breaking the deposit-heat cycle that plagues conventional oils. For compressors operating in hydrocarbon gas service, Synfilm® NGL and NGL-NS™ are formulated with dense, closely packed synthetic molecules that greatly resist dilution from compressed gases. NGL-NS™ is virtually sulfur-free, making it ideal for installations with sulfur-sensitive catalysts downstream. CAP 700/460 provides additional specialized protection for compressor applications operating under demanding process conditions.
Problem
Compressing gases beyond standard air introduces a range of lubrication challenges that conventional oils simply cannot address. Hydrocarbon gases such as ethylene, propane, butane, and natural gas dissolve into and dilute conventional lubricants, reducing viscosity and stripping away the protective oil film. Hydrogen, ammonia, and corrosive gases demand chemically inert lubricants that will not react with the compressed medium. Food, beverage, and pharmaceutical compressor applications require lubricants that meet strict FDA and NSF regulatory standards. Choosing the wrong oil for these specialized applications can result in compressor damage, product contamination, or regulatory violations.
Solution
Our specialty compressor lubricants are engineered for the specific demands of gas compression beyond air. Crystal-Clear® meets all of the requirements of a white mineral oil but delivers the superior lubrication of a synthetic by resisting dilution from hydrocarbon gases, while excelling in hydrogen, sulfur dioxide, nitrogen, CO2, helium, ethylene, propane, and LPG compressor service. Crystal-Pure® extends this capability with enhanced purity for sensitive applications. For food and pharmaceutical compressor environments, Poly-Guard® FDA delivers NSF-certified food-grade protection without compromising performance. Uni-Temp™ offers reduced solubility with ammonia and superior low-temperature pumpability for refrigeration compressors. Alkalube™ rounds out the lineup for additional process gas applications, and VP Preservative Oil protects idle or stored compressor components from rust and corrosion between service intervals.
Featured Products for Compressor Applications
Improve Your Compressor Reliability
Let our synthetic experts recommend the right products and reliability solutions for your compressor applications. Contact us today.