What is Base Oil SN500? A Complete Guide
Base Oil SN500 is one of the most widely used base stocks in the lubricant industry. It plays a crucial role in the formulation of automotive and industrial oils due to its balance of performance and cost-effectiveness. In this blog post, we will explore what SN500 base oil is, how it’s produced, its key properties, and why it is so important in lubrication systems.
What is Base Oil SN500?
Base Oil SN500 is a Group I solvent neutral mineral base oil with medium-to-high viscosity. It is produced through a refined distillation of crude oil, followed by solvent extraction and dewaxing processes. The “SN” in SN500 stands for Solvent Neutral, and the number “500” represents its average kinematic viscosity at 40°C.
SN500 is a light amber, transparent oil that is ideal for blending with additives to produce a variety of finished lubricants.
How is SN500 Produced?
The production of SN500 typically involves the following stages:
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Crude Oil Distillation: Crude oil is heated and separated into fractions, including the base oil cut.
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Solvent Extraction: Aromatics and impurities are removed using selective solvents.
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Dewaxing: Improves the pour point and cold flow characteristics.
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Finishing: Further purification to meet standard specifications.
The final product is a relatively pure mineral oil, retaining a moderate amount of sulfur and unsaturated hydrocarbons, which contributes to good solvency for additives.
Key Properties of SN500 Base Oil
| Property | Typical Value |
|---|---|
| Kinematic Viscosity @ 40°C | ~ 95–105 cSt |
| Kinematic Viscosity @ 100°C | ~ 10.5–11.5 cSt |
| Viscosity Index (VI) | ~ 90–100 |
| Flash Point | ~ 230–250°C |
| Pour Point | ~ -6°C to -9°C |
| Color (ASTM) | ≤ 2.0 |
| Sulfur Content | Moderate (Group I) |
These properties make SN500 ideal for applications where lubrication performance and cost control are both important.
SN500 refers to the viscosity grade of the base oil, with “SN” indicating its suitability for use in lubricants and “500” representing its kinematic viscosity at 100 degrees Celsius. The kinematic viscosity of SN500 typically ranges from 450 to 550 centistokes (cSt) at this temperature.
Base Oil SN500 is commonly used in applications that require higher viscosity and lubricating properties. It is suitable for use in various industrial lubricants, including hydraulic fluids, gear oils, compressor oils, and metalworking fluids.
Additionally, Base Oil SN500 offers good compatibility with additives, allowing formulators to customize lubricant formulations to meet specific performance requirements. By blending SN500 with other base oils or additives, lubricants can be tailored to achieve desired viscosity grades and enhanced performance characteristics.
When selecting Base Oil SN500 for a particular application, it is important to consider factors such as the operating conditions, equipment requirements, and lubricant specifications. Consulting with lubricant formulators or experts can help determine the optimal base oil and formulation to achieve the desired performance objectives.
Common Applications of SN500
SN500 is used as a foundational base stock in:
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Automotive engine oils (especially monograde oils)
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Gear oils
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Hydraulic fluids
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Transmission fluids
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Industrial greases
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Metalworking fluids
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Marine and railroad oils
Its excellent additive solvency makes it easy to blend with performance-enhancing additives, while its thermal stability ensures long-term protection of machinery and engines.
Advantages of SN500 Base Oil
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✅ Cost-effective: Less expensive than Group II/III base oils
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✅ Good solvency: Dissolves additives and contaminants effectively
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✅ Blending flexibility: Suitable for blending with lighter or heavier base stocks
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✅ Readily available: Widely produced and globally traded
One of the key advantages of using Base Oil SN500 is its excellent thermal stability and resistance to oxidation. This helps extend the life of the lubricant and maintain its performance even at high temperatures, reducing the risk of degradation and sludge formation.
SN500 also provides good film strength and load-carrying capacity, making it suitable for applications where heavy loads and high pressures are involved. It helps reduce friction and wear between moving parts, ensuring smooth operation and protecting machinery from damage.
Limitations of SN500
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❌ Lower oxidation stability compared to Group II and III oils
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❌ Higher sulfur and aromatic content
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❌ Shorter drain intervals under extreme operating conditions
While SN500 is an economical and versatile option, applications that demand very high thermal or oxidative stability may require more refined Group II or synthetic base oils.
SN500 vs. SN150 vs. SN650
| Property | SN150 | SN500 | SN650 |
|---|---|---|---|
| Viscosity (40°C) | ~30 cSt | ~100 cSt | ~125 cSt |
| Applications | Light-duty oils | General-purpose lubes | Heavy-duty lubes |
| Flow Properties | Excellent | Good | Moderate |
SN500 provides a middle ground between SN150 (lighter) and SN650 (heavier) base oils, making it ideal for many general-purpose lubricants.
FAQs About SN500
Q1: Is SN500 a synthetic oil?
No, SN500 is a mineral oil classified under Group I base oils. It is not synthesized like Group IV (PAO) or Group V oils.
Q2: Can SN500 be used in engine oils?
Yes. SN500 is often used as a base for monograde and multigrade engine oils, particularly when blended with SN150 and performance additives.
Q3: What is the difference between SN500 and SN650?
The main difference is viscosity. SN650 is thicker and used in heavier-duty applications, while SN500 offers a medium viscosity suitable for general use.
Q4: Is SN500 suitable for cold temperatures?
SN500 has a moderate pour point, which may not be ideal for very cold climates without the addition of pour point depressants.
Q5: Where is SN500 commonly produced?
SN500 is produced by refineries worldwide, especially in regions with significant petroleum refining capacity, such as the Middle East, Asia, Russia, and North America.
Conclusion
Base Oil SN500 remains a staple in lubricant production due to its optimal balance of viscosity, solvency, and cost. Whether used alone or blended with other base stocks and additives, SN500 delivers reliable performance for both automotive and industrial applications.
Understanding the characteristics and applications of SN500 helps manufacturers and users choose the right oil for their machinery, ensuring performance, longevity, and efficiency.
✅ Looking for a Trusted SN500 Supplier?
At Pars Universal Bitumen, we specialize in the supply and export of premium-grade Base Oil SN500 to clients across the globe.
🌍 Serving markets in Asia, Africa, and Europe
⚙️ Supplying to lubricant manufacturers, traders & industries
📦 Bulk orders, flexible packaging & logistics support available
Whether you’re producing automotive oils, industrial lubricants, or grease formulations, our SN500 is refined to meet your exact needs.
📧 Email: info@pub-ltd.com
📞 Phone: +971 4 878 2031
🌐 Visit: Pub-ltd
📞 Contact Pars Universal Bitumen today for competitive pricing, sample requests, or technical specifications.
📧 Request a quote now — and let us power your production with consistent quality and global reliability.
