LYLC-492 Synthetic Ester Transformer Oil
High-Performance Dielectric Insulating Fluid for Power Transformers & Electrical Equipment
Premium Synthetic Ester Insulating Fluid
LYLC-492 is an ester-based synthetic dielectric insulating liquid compliant with IEC 61099 and ASTM D8240. Featuring a high flash point, high fire point, excellent low-temperature flow properties, and strong environmental compatibility, it is suitable for indoor, outdoor, and underground power transformer installations.
Proven in applications up to 433 kV, LYLC-492 delivers outstanding oxidation stability for both sealed and free-breathing transformer designs. Its ultra-low pour point (−56°C) ensures reliable performance in the most demanding cold-climate environments.
Unlike conventional mineral oil — which degrades rapidly when exposed to even small amounts of moisture — LYLC-492 tolerates up to ~600 ppm of dissolved water while maintaining full dielectric performance. This exceptional moisture management capability extends cellulose paper insulation life, reduces maintenance frequency, and provides a critical safety margin for transformers in humid or coastal environments.
As a cost-effective alternative to Midel 7131, LYLC-492 is manufactured by PetroChina's Kunlun Lubricant division — one of the largest petroleum companies in the world — and distributed exclusively through our global network. European end-user validation has confirmed excellent performance across all IEC parameters.
Fire Safety
Fire point >300°C, K3 class per IEC 61039. Ideal for indoor, outdoor, and underground installations.
Extreme Cold Performance
Pour point as low as −56°C. Reliable operation in arctic and high-altitude environments.
Environmentally Friendly
Readily biodegradable. No adverse effect on activated sludge. PCB-free.
Superior Dielectrics
Breakdown voltage >75 kV. Excellent moisture tolerance up to 600 ppm while maintaining insulation performance.
Extended Paper Life
Absorbs moisture from cellulose insulation, extending transformer paper life and reducing maintenance costs.
Design Flexibility
Supports compact transformer designs with higher operating temperatures under standard lifespan conditions.
Independently Tested & Certified
LYLC-492 has been tested by world-renowned laboratories and fully complies with international standards for synthetic ester insulating fluids.
Doble Engineering
Full compliance with IEC 61099:2010 — Doble Report 247890.1 (Feb 2021)
Siemens Energy Nuremberg
Tested at DAkkS-accredited lab — Report ML096-21 (May 2021)
IEC 61099:2010
Full compliance with Specification Sheet 1 for unused synthetic organic esters
Carbon Footprint Certified
2.79 tCO₂eq per tonne (cradle-to-gate), verified per ISO 14067 & PAS 2050
European End-User Validated
Independently tested by a major European utility grid operator's insulating oil laboratory (March 2026)
Technical Specifications
Complete performance data tested per IEC 61099:2010. LYLC-492 meets or exceeds all standard requirements.
Performance Data — LYLC-492 vs. IEC 61099 Limits
| Property | Condition / Unit | Test Method | IEC 61099 Limit | LYLC-492 | Result |
|---|---|---|---|---|---|
| Physical Properties | |||||
| Appearance | Visual | Visual | Clear, free from suspended matter | Clear, no sediment | ✓ Pass |
| Colour | Hazen | ISO 2211 | ≤ 200 | 40 | ✓ Pass |
| Density at 20°C | kg/m³ | ISO 12185 | ≤ 1,000 | 966.6 | ✓ Pass |
| Kinematic Viscosity at 40°C | mm²/s | ISO 3104 | ≤ 35 | 27.94 | ✓ Pass |
| Kinematic Viscosity at −20°C | mm²/s | ISO 3104 | ≤ 3,000 | 1,256 | ✓ Pass |
| Flash Point (Closed Cup) | °C | ISO 2719 | ≥ 250 | 255 | ✓ Pass |
| Fire Point | °C | ISO 2592 | ≥ 300 | 314 | ✓ Pass |
| Pour Point | °C | ISO 3016 | ≤ −45 | −63 | ✓ Pass |
| Chemical Properties | |||||
| Acid Value (Neutralization) | mg KOH/g | IEC 62021-1 | ≤ 0.03 | 0.01 | ✓ Pass |
| Moisture Content | mg/kg | IEC 60814 | ≤ 200 | 70 | ✓ Pass |
| Oxidation Stability (164 h) — Total Acidity | mg KOH/g | IEC 61125C | ≤ 0.3 | 0.03 | ✓ Pass |
| Oxidation Stability (164 h) — Total Sludge | % mass | IEC 61125C | ≤ 0.01 | <0.01 | ✓ Pass |
| Electrical Properties | |||||
| Breakdown Voltage | kV | IEC 60156 | ≥ 45 | 88 | ✓ Pass |
| Dielectric Dissipation Factor (90°C) | tan δ | IEC 60247 | ≤ 0.03 | 0.0158 | ✓ Pass |
| DC Resistivity at 90°C | GΩ·m | IEC 60247 | ≥ 2.0 | 4.6 | ✓ Pass |
| Environmental & Compliance | |||||
| Biodegradability (28 days) | % | OECD 301 | — | Readily biodegradable | ✓ |
| Classification | — | IEC 61039 | — | K3 Class | ✓ |
Head-to-Head Comparison: LYLC-492 vs. Midel 7131
LYLC-492 matches or outperforms the leading incumbent synthetic ester across all key parameters.
| Property | IEC 61099 Limit | LYLC-492 | Midel 7131 | Advantage |
|---|---|---|---|---|
| Colour (Hazen) | ≤ 200 | 40 | 43 | LYLC-492 |
| Density 20°C (kg/m³) | ≤ 1,000 | 966.6 | 966.9 | Comparable |
| Viscosity at 40°C (mm²/s) | ≤ 35 | 27.94 | 28.21 | LYLC-492 |
| Viscosity at −20°C (mm²/s) | ≤ 3,000 | 1,256 | 1,337 | LYLC-492 |
| Flash Point (°C) | ≥ 250 | 255 | 253 | LYLC-492 |
| Fire Point (°C) | ≥ 300 | 314 | 312 | LYLC-492 |
| Pour Point (°C) | ≤ −45 | −63 | −60 | LYLC-492 |
| Acid Value (mg KOH/g) | ≤ 0.03 | 0.01 | 0.02 | LYLC-492 |
| Moisture (mg/kg) | ≤ 200 | 70 | 68 | Comparable |
| Oxidation Acidity 164h (mg KOH/g) | ≤ 0.3 | 0.03 | 0.18 | LYLC-492 (6×) |
| Breakdown Voltage (kV) | ≥ 45 | 88 | 84 | LYLC-492 |
| DDF tan δ (90°C) | ≤ 0.03 | 0.0158 | 0.0265 | LYLC-492 |
| DC Resistivity 90°C (GΩ·m) | ≥ 2.0 | 4.6 | 6.0 | Midel 7131 |
Moisture Management — A Critical Advantage
Moisture is the number one enemy of transformer insulation. LYLC-492 turns this challenge into a strength — absorbing and managing water far beyond what mineral oil can tolerate, extending equipment life and reducing maintenance costs.
Why Moisture Matters in Transformers
Water in transformer insulation accelerates cellulose paper aging, reduces dielectric strength, and ultimately leads to premature failure. Conventional mineral oil can only tolerate approximately 30–50 ppm of dissolved water before performance degrades. Even a small moisture ingress event — from a faulty gasket, humidity during maintenance, or normal breathing cycles — can push mineral oil past its safe limit.
How LYLC-492 Solves This
Synthetic ester fluids like LYLC-492 are inherently hygroscopic — they absorb and hold moisture at levels that would be catastrophic in mineral oil, while maintaining full dielectric performance. LYLC-492 can operate safely with up to ~600 ppm of dissolved water while keeping breakdown voltage well above the 45 kV minimum. Its saturation limit of approximately 2,700 ppm at 20°C means that virtually no free water forms in the fluid, eliminating the risk of water-induced flashover.
Extending Cellulose Insulation Life
LYLC-492 actively draws moisture out of the cellulose paper insulation and into the fluid, where it is safely dissolved. This moisture migration effect slows paper degradation, extending the service life of transformer insulation by years. For asset managers, this translates directly into fewer oil treatments, longer maintenance intervals, and deferred capital replacement.
Mineral Oil
LYLC-492 Synthetic Ester
* Based on independent third-party laboratory testing of LYLC-492 after extended air transport. Breakdown voltage of 69 kV was recorded at 442 mg/kg water content — still well above the IEC 61099 minimum of 45 kV.
Applications
LYLC-492 is engineered for demanding electrical installations where fire safety, environmental protection, and long service life are critical.
Power Grid & Substations
High-rise buildings, underground substations, and urban infrastructure where fire safety codes demand K-class insulating fluids.
- Indoor and underground substations
- High-rise building transformers
- Data center power distribution
- Hospital and public facility substations
Renewable Energy
Offshore wind farms, solar power stations, and energy storage systems requiring biodegradable, fire-resistant transformer fluids.
- Offshore and onshore wind turbine transformers
- Solar farm collector transformers
- Offshore drilling platforms
- Marine and shipboard electrical equipment
Rail & Transportation
High-speed rail traction transformers and electric locomotive systems demanding ultra-low pour point and fire-safe fluids.
- High-speed rail traction transformers
- Electric locomotive power systems
- Metro and light rail substations
- Railway trackside power transformers
Packaging & Storage
Packaging Options
- 200 L steel drums — Net weight 180 ± 2 kg
- IBC totes — 1,000 kg
- ISO tank container available for bulk orders
- Custom packaging available on request
Storage Guidelines
- Store in a dry, ventilated area — preferably indoors
- Use dedicated containers only — never mix with mineral oils
- Keep sealed and moisture-free until use
- Keep away from open flames and oxidizing agents
About Us
Lyson, established in 2018, is a subsidiary of a parent company that has been in business for over 30 years. The parent company also has subsidiaries in Tokyo and Frankfurt. This gives us access to a global network of silicone-based raw material suppliers and customers.
why Us?
At Lyson, we offer more than just export service. We offer value-added trade services that include:
- Free sourcing service until you are satisfied with the quality, quantity, cost, timing, and packaging of your order
- Up-to-date market insights and advice to help you make informed decisions and avoid price fluctuations
- Quality guarantee and testing before purchasing to ensure you get the best products for your needs
- Fast and accurate sourcing thanks to our 30 years of local supply chain network and experience
Contact Us
Call Us
Tel:+86 21 3363 2226
Lyson Chem-Materials Shanghai Company
sales@lysonchem-materials.com
Room 421, No. 62 – 421, Hongcao Road, Xuhui, Shanghai,
China 200233
Tel:+49 (0) 6102 8837308
GW United Chemicals GmbH
info@gwunitechem.com
Max-Holder-19, Frankfurt,
Germany
Tel:+81 3 3436 2520
GW Chemicals Nippon
info@gwchem.jp
東京都港区虎ノ門3丁目22番14号 エミタス虎ノ門ビル, “Isenburg” , “1201”
Japan
Tel:+1 347 9400534
GW United Chemicals USA Inc.
info@gwunitedchem.com
165 Broadway, 23rd Floor, New York, 10006
United States of America
Lyson Chem Product List
| PRODUCT | CAS No. |
|---|---|
| Dimethyl Silicone Fluid 0.65cst 1cs 1.5cst 2cst 3cst | 107-46-0, 107-51-7, 141-62-8, 141-63-9, 63148-62-9 |
| Dimethyl Silicone Fluid 20cst 50cst 100cst 350cst 500cst 1000cst | 63148-62-9 |
| Dimethyl Silicone Fluid 10000cst 12500cst 60000cst | 63148-62-9 |
| Hydroxy Silicone Fluid | 70131-67-8 |
| OH Polymer | 70131-67-8 |
| Vinyl Silicone Fluid | 63148-62-9 |
| Methyl Hydrogen Silicone Fluid | 63148-57-2 |
| Hydrogen-terminated Silicone Fluid | 70900-21-9 |
| Amino Silicone Fluid | 63148-62-0 |
| Methyl Phenyl Silicone Fluid | 63148-52-7, 63148-58-3 |
| Phenyl Vinyl Silicone Fluid | 225927-21-9 |
| Phenyl Hydrogen Silicone Fluid | 17875-55-7 |
| Methyl Fluoro Silicone Fluid | 63148-56-1 |
| Diffusion Pump Silicone Fluid | 3982-82-9, 3390-61-2 |
| Stearoyl Benzoyl Methane - SBM | 58446-52-9 |
| Hexamethyldisiloxane | HMDSO | 107-46-0 |
| heptamethyltrisiloxane | HPTSO | 1873-88-7 |
Frequently Asked Questions
A: Here are the three third parties, they offer testing services, and we send our sample to them before
www.exponent.com
www.rjlg.com