I. Product Background and Standards

1. Development Background: RP4350 breaks China's long-term reliance on petroleum-based aviation hydraulic fluids. It represents a significant achievement in addressing domestic demand for fire-resistant hydraulic fluids. Its development aligns with U.S. military standard MIL-H-83282 and complies with Chinese military standard GJB 5311A-2015, matching the performance of international products like Shell 31 and NICO FH2.

2. Technical Standards: Meets MIL-PRF-83282D specifications. Flashpoint reaches 205°C (some data indicate 209°C). Operational temperature range spans -40°C to 205°C, though low-temperature startup performance slightly lags behind traditional No. 15 aviation hydraulic fluid.

II. Performance Characteristics

1. Fire Resistance: Based on polyalphaolefin (PAO) base oil, its flashpoint far exceeds mineral oils (e.g., No. 10 hydraulic fluid with ~90°C flashpoint). Fire resistance is comparable to international FH2 fluids, significantly reducing fire risks in hydraulic systems.

2. Broad Temperature Adaptability:

• High Temperature: Withstands over 200°C with excellent oxidation stability.

• Low Temperature: Pour point as low as -56°C, but kinematic viscosity at -40°C may affect cold-start performance.

3. Compatibility: Compatible with petroleum-based fluids and synthetic seals (e.g., nitrile rubber), facilitating system upgrades.

4. Physical Parameters: Specific gravity 0.92; kinematic viscosity at 40°C: 12.8 cSt; viscosity grade 10 (L-HV category); packaging: 3.5 kg/drum; manufactured in Beijing.

III. Applications

1. Military Aviation: Widely used in helicopter hydraulic systems (e.g., Z-9), missile servo controls, brakes, and flap actuators.

2. Extended Scenarios: Suitable for autopilot systems, air compressor gearboxes, and other high-temperature, fire-resistant hydraulic systems with synthetic seals.

3. Import Substitution: Matches performance of Shell 31 and NICO FH2, supporting domestic upgrades for new aircraft and low-altitude vehicles.

IV. Market and Production

1. Production and Supply: Manufactured under license from Sinopec Research Institute of Petroleum Processing (RIPP) and marketed under the Xingpu brand. Full technical documentation and test reports are provided.

2. Domestication Significance: Reduces import dependency, drives hydraulic system modernization in military and civilian sectors, and meets high-temperature and safety requirements for new-generation equipment.

V. Limitations

• Low-Temperature Performance: Despite a -56°C pour point, kinematic viscosity at -40°C may exceed that of No. 15 fluid, necessitating optimization for cold starts.

• Competition: Requires continuous innovation to compete with international brands (e.g., Skydrol phosphate ester fluids) in civil aviation markets.

VI. Future Outlook

As a cornerstone for China's military aviation hydraulic systems, RP4350 is expected to expand its applications and improve low-temperature performance through iterative upgrades. Growing demand is anticipated alongside advancements in domestic aviation industries.