FR3® Natural Ester
Overview
FR3® Natural Ester is a transformer insulating and cooling fluid made from more than 99% soybean oil. With over 30 years in service and more than 5 million transformers filled worldwide, it is the original and most widely used natural ester.
Its fire point exceeds 350 °C, more than twice that of mineral oil, making it a K-class less-flammable fluid. It draws moisture out of the cellulose paper insulation, slowing its ageing. It contains no petroleum, halogens, silicones or PCBs and is readily biodegradable.
Applications
Distribution and power transformers, pad- and pole-mount units, indoor and urban substations, wind and solar plants, data centers, rail and battery energy storage. Also used to retrofill existing mineral-oil transformers.
Typical Properties
| Base | Natural ester (>99% soybean oil) |
|---|---|
| Fire point (ASTM D92) | > 350 °C |
| Flash point, COC (ASTM D92) | > 320 °C |
| Flash point, PMCC (ASTM D93) | > 260 °C |
| Pour point (ASTM D97) | −21 °C |
| Density (20 °C) | 0.92 g/cm³ |
| Viscosity (100 °C) | 8 mm²/s |
| Water content (IEC 60814) | < 50 mg/kg |
| Fire class | K-class |
| Standards | IEC 62770 · IEEE C57.147 · ASTM D6871 |
| Produced in | Dilovası, Türkiye |
Typical values, not specifications. Request the full technical data sheet for test methods and results.
Frequently Asked Questions
Where can I buy FR3® transformer fluid?
Oilsan supplies FR3® Natural Ester across Türkiye and worldwide. It is produced in Dilovası, Türkiye. Call +90 212 909 93 36 or email info@oilsan.com for a quote.
More Transformer Fluids
FR3r™ Natural Ester
Rapeseed-based FR3r™ natural ester: K-class fire safety, up to 8x longer paper insulation life, IEC 62770, readily biodegradable. Supplied worldwide by Oilsan.
Transformer FluidsView product →SE3® Synthetic Ester
SE3® synthetic ester transformer fluid: fire point above 300 °C (K-class), pour point below −50 °C, IEC 61099, readily biodegradable. IBC (910 kg). Supplied worldwide by Oilsan.
Transformer FluidsView product →Right lubricant.
Less downtime.
Tell us about your application and we’ll recommend the right product.