SN150
Light Industrial
KV @ 100°C5.36 mm²/s
VI119
Flash Point214 °C
Pour Point−10 °C
Best forHydraulic oils, light industrial lubricants, general-purpose machine oil, white oil feedstock.
API Group I · Solvent-Refined Paraffinic
Group I Base Oil — SN150, SN250, SN500, SN650 & Bright Stock 150BS
Five solvent-refined paraffinic grades for industrial lubricants, rubber process oil, marine engine oils and heavy gear formulations. SGS-inspected, full TDS and COA with every shipment.
5
Viscosity Grades
80–120
Viscosity Index
SGS
Quality Verified
500+
Customers Worldwide
About Group I Base Oil
The most established base stock for industrial & specialty lubricants
Group I base oil is produced by solvent refining of vacuum distillates — the original industrial route that has powered lubricant manufacturing for over 70 years.
It contains under 90% saturates, over 0.03% sulphur and has a viscosity index between 80 and 120. While Group II and III dominate modern automotive lubes, Group I remains the preferred base stock for many industrial, marine, rubber and process-oil applications — where its higher aromatic content actually improves solvency, additive compatibility and seal performance.
Sinolook supplies five Group I grades — SN150, SN250, SN500, SN650 and Bright Stock 150BS — sourced from established refineries with consistent batch-to-batch quality and full SGS verification on every shipment.
Wide Viscosity Range
KV100 from 5.4 to 31.7 mm²/s — covering light industrial to heavy marine oils.
Stable Long-Term Supply
Sourced from established refineries with multi-year agreements — never short on stock.
Excellent Solvency
Higher aromatic content improves additive solubility and elastomer compatibility.
Cost-Effective
Significantly lower price than Group II/III — ideal where premium VI is not required.
Technical Specifications
Five Group I grades — full specification table
Typical values from recent production batches. Specifications conform to ASTM and GB/T standards. Batch-specific COA available with each shipment.
| Property | SN150 | SN250 | SN500 | SN650 | BS150 (Bright Stock) | Test Method |
|---|---|---|---|---|---|---|
| KV @ 40°C (mm²/s) | 29.13 | 41.25 | 93.32 | 132.0 | 486.6 | ASTM D445 |
| KV @ 100°C (mm²/s) | 5.36 | 6.793 | 10.31 | 13.19 | 31.71 | ASTM D445 |
| Viscosity Index | 119 | 121 | 90 | 93 | 96 | ASTM D2270 |
| Density @ 20°C (g/cm³) | 0.8446 | 0.8457 | 0.8899 | 0.8910 | 0.9024 | ASTM D4052 |
| Flash Point (°C, COC) | 214 | 238 | 258 | 266 | 316 | ASTM D92 |
| Pour Point (°C) | −10 | −12 | −9 | −9 | −6 | ASTM D97 / D5950 |
| Color (ASTM) | 0.75–1.0 | 1.0 | 2.5 | 3.0 | L2.0 | ASTM D1500 |
| Acid Number (mg KOH/g) | 0.01 | 0.02 | 0.020 | 0.020 | 0.02 | ASTM D664 / D974 |
| Carbon Residue (%) | — | — | 0.051 | 0.112 | 0.43 | ASTM D4530 |
| Oxidation Stability (RPVOT, min) | — | — | 180 | 180 | — | ASTM D2272 |
Values are typical and indicative. Refer to the latest product TDS and COA for batch-specific results. Test methods: ASTM American / GB/T China national standards.
Grade Selection Guide
Choose the right Group I grade for your formulation
Each grade is optimised for a specific viscosity range and application. Click "Request quote" to receive batch-current COA and pricing.
SN250
Medium Duty
KV @ 100°C6.79 mm²/s
VI121
Flash Point238 °C
Pour Point−12 °C
Best forTurbine oils, medium-duty machine lubricants, transformer oil components, industrial gear oil blending.
SN500
★ Most Popular
KV @ 100°C10.31 mm²/s
VI90
Flash Point258 °C
Pour Point−9 °C
Best forIndustrial gear oils, rubber process oil (RPO), heat-transfer fluids, marine system oils, grease base.
SN650
Heavy Duty
KV @ 100°C13.19 mm²/s
VI93
Flash Point266 °C
Pour Point−9 °C
Best forHeavy industrial gear oils, way oils, paper-mill oils, calender oils, asphalt extender, mining lubricants.
BS150 — Bright Stock
High Viscosity Residual
KV @ 100°C31.71 mm²/s
VI96
Flash Point316 °C
Pour Point−6 °C
Best forMarine engine oils (cylinder & system), heavy gear oils (ISO VG 320–680), wire-rope lubricants, steam-turbine oils.
Need a specific cut?
Custom blending and intermediate viscosities available on request.
Get Custom Quote
How It's Made
The solvent refining process
Group I is produced through the classic solvent refining route. Vacuum gas oil from atmospheric residue is treated in four distinct steps to extract paraffinic base oil and remove unwanted aromatics, wax and asphaltenes.
Applications
Where Sinolook Group I base oil performs best
Group I's higher solvency and lower cost make it the preferred base stock for industrial lubricants, rubber compounding, marine engine oils and process oils — applications where Group II/III provide no meaningful performance advantage.
Packaging & Logistics
Flexible delivery options worldwide
From drum to bulk vessel. Bonded storage at Yingkou, Nantong and Guangdong (China), plus partner facilities in Singapore, Malaysia and Asia-Pacific hubs.
Drum (200 L)
80 drums per 20' container · sealed steel drum
Flexitank (24 MT)
Per 20' container · single-use food-grade liner
ISO Tank (20–22 MT)
Heated, insulated · reusable
Bulk Vessel
1,000+ MT · direct shore-to-shore
FAQ
Frequently asked questions
What is Group I base oil?
Group I base oil is solvent-refined paraffinic base oil with less than 90% saturates, greater than 0.03% sulphur and a viscosity index between 80 and 120. It is the oldest and most widely used base stock type, well-suited for industrial lubricants, rubber process oils, marine engine oils and heavy gear oils where extreme performance properties are not required.
What is the difference between SN and BS in Group I base oil?
SN stands for Solvent Neutral and describes lighter to medium viscosity Group I grades produced by solvent refining of distillate fractions.
BS stands for Bright Stock and refers to high-viscosity, dark Group I oil produced from residual fractions after deasphalting and further refining. Bright Stock has much higher viscosity, flash point and thermal stability than SN grades, making it ideal for marine engines and very heavy gear oils.
BS stands for Bright Stock and refers to high-viscosity, dark Group I oil produced from residual fractions after deasphalting and further refining. Bright Stock has much higher viscosity, flash point and thermal stability than SN grades, making it ideal for marine engines and very heavy gear oils.
Which Group I grade should I choose?
Choose by required viscosity at 100°C:
• SN150 (KV100 = 5.4) — hydraulic and light industrial oils
• SN250 (6.8) — turbine and medium-duty machine oils
• SN500 (10.3) — gear oils, rubber process oil, marine system oils
• SN650 (13.2) — heavy gear oils, way oils, mining lubricants
• BS150 / Bright Stock (31.7) — marine cylinder oils and ISO VG 320–680 gear oils.
• SN150 (KV100 = 5.4) — hydraulic and light industrial oils
• SN250 (6.8) — turbine and medium-duty machine oils
• SN500 (10.3) — gear oils, rubber process oil, marine system oils
• SN650 (13.2) — heavy gear oils, way oils, mining lubricants
• BS150 / Bright Stock (31.7) — marine cylinder oils and ISO VG 320–680 gear oils.
Why does SN500 have a lower VI than SN150?
In Group I solvent refining, higher viscosity grades come from heavier vacuum distillate cuts that contain more naphthenic and aromatic molecules. These molecules reduce the viscosity index. This is normal for Group I — SN500 typically shows VI 90–100, while SN150 reaches VI 110–120. For applications requiring higher VI at high viscosity, consider Group II hydrocracked base oil instead.
How is Sinolook Group I base oil packaged?
Flexitank (24 MT per 20' container), ISO tank (20–22 MT), 200-litre drums (80 drums per 20' container), and bulk vessel (1,000+ MT direct shore-to-shore). Bonded storage available at Yingkou, Nantong and Guangdong in China, plus partner facilities in Singapore, Malaysia, and other Asia-Pacific hubs.
What documents accompany each shipment?
Every shipment includes:
• Third-party SGS Certificate of Quality
• Manufacturer Certificate of Analysis (COA)
• Technical Data Sheet (TDS) and Safety Data Sheet (SDS)
• Bill of Lading, packing list, commercial invoice
• Certificate of Origin (on request)
• Third-party SGS Certificate of Quality
• Manufacturer Certificate of Analysis (COA)
• Technical Data Sheet (TDS) and Safety Data Sheet (SDS)
• Bill of Lading, packing list, commercial invoice
• Certificate of Origin (on request)
Can I request samples before placing an order?
Yes. Sinolook provides 500ml to 1L laboratory samples for formulation evaluation. Sample requests are subject to courier cost. Email sales@sinolook.com with the grade and quantity required.
What payment terms does Sinolook accept?
L/C at sight, T/T 30% advance with 70% before B/L copy, or D/P at sight for established customers. Detailed terms vary by order size and destination country — contact our sales team for a tailored proposal.
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Need a Group I base oil quote?
Tell us the grade(s), volume and destination port — we'll respond within 24 hours with batch-current COA, SGS report, pricing and logistics options.
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