Extend the life and reliability of your phosphate ester systems
Phosphate ester oils are essential in electro-hydraulic control systems because they are fire resistant and allow turbines to react with precision. These fluids, however, are highly sensitive to moisture, oxidation, and chemical breakdown. Once contaminated, they lose resistivity, form acidic byproducts, and generate sludge that causes servo valve sticking and control drift.
Because phosphate ester fluids are costly to replace, maintenance managers face increasing operational risk when these degradation processes accelerate. CJC® Offline Filtration stabilises the fluid continuously, removing water, acids, varnish, and fine particles, so EHC systems remain reliable and turbine operation stays predictable.
What challenges phosphate ester fluids in turbine control systems
Steam and gas turbines operate under different conditions, but both expose lube oil to contamination that cannot be prevented by design alone.
High water affinity drives rapid degradation
Phosphate ester oils absorb moisture easily, lowering electric resistivity and destabilising EHC performance. Even small increases in water content accelerate hydrolysis, leading to acidic byproducts and corrosion of sensitive components.
Hydrolysis increases acidity and shortens fluid life
When moisture and temperature interact, phosphate ester oil breaks down chemically. TAN rises, acids attack metals and elastomers, and the fluid’s fire-resistant properties decline. High TAN typically forces premature oil replacement, increasing operating costs.
Varnish and sludge disturb servo valve operation
Oxidation residues form soft contaminants that settle in tight valve tolerances. This leads to sticky or drifting servo valves, unreliable turbine response, and potential control system trips during start-up or load changes.
Contamination reduces electrical stability
As phosphate ester oil degrades, its resistivity drops, affecting sensors and the stability of the EHC system. Lower resistivity increases the risk of control disturbances and unplanned turbine stops.
When phosphate ester oil becomes unstable, valves stick, acidity rises, and turbine control becomes unreliable. This leads to more maintenance, shorter oil life, and a higher risk of EHC-related trips. Keeping the fluid clean, dry, and chemically stable is the most effective way to protect turbine performance.
How it works
Phosphate ester fluids degrade when water, acids, and soft contaminants are left circulating in the system. CJC® Offline Filtration removes these continuously, keeping EHC systems stable and predictable.
How the Offline Principle Works
Outcome for Turbine Operators
Fewer servo valve sticking events
Cleaner oil keeps control valves operating freely, reducing sticking events and ensuring smoother, faster turbine response even during load changes.
Lower TAN progression
By slowing oxidation and acid formation, the fluid maintains its protective properties longer -extending oil life and reducing the need for corrective maintenance
Stable ISO cleanliness
Effective fine filtration maintains consistent cleanliness levels, even under high thermal stress, protecting sensitive components from wear and varnish deposits.
Reduced maintenance hours
Reliable oil quality lowers intervention frequency and enables more predictable control system performance, freeing maintenance teams to focus on critical tasks.
Where phosphate ester oil is used and how CJC® improves performance
Electro-Hydraulic Control (EHC) systems on steam turbines
Challenge: Moisture and oxidation residues cause servo valve sticking and unstable control.
Result: Cleaner, drier fluid with stable ISO codes and smoother valve response.
Generator brake and protection circuits
Challenge: Soft contaminants and water disturb fast-acting hydraulic components.
Result: Improved reliability of braking sequences and reduced wear on critical actuators.
Gas turbine hydraulic control and trip systems
Challenge: High temperatures accelerate oxidation and acid formation, raising TAN.
Result: Offline filtration reduces residues and slows TAN progression for better long-term stability.
Fire-resistant HFDR fluid systems
Challenge: These fluids are difficult to maintain with conventional inline filters, and degradation accelerates when moisture is present.
Result: Depth filtration removes ultra-fine particles, water, and sludge, helping preserve fire-resistant properties.
Documented Performance in Real Turbine Systems
Water content is reduced to safe EHC operating levels
Phosphate ester fluids absorb moisture easily. CJC® Offline Filtration reduces both free and dissolved water, allowing plants to bring the fluid back into the moisture range recommended by EHC system and turbine OEMs. Lower moisture slows hydrolysis and helps maintain electrical resistivity.
TAN progression slows once water and oxidation products are removed
When hydrolysis is brought under control, the Total Acid Number stabilises. In documented EHC systems with rising TAN, CJC® filtration stopped the increase and allowed operation to continue without immediate fluid replacement.
Soft contaminants, varnish residues, and sludge are significantly reduced
Depth filtration with cellulose media removes oxidation byproducts that accumulate in tight valve clearances. Plants report restored actuator and servo valve performance once these soft contaminants are removed from the fluid.
System reliability improves as valve sticking incidents decrease
After restoring cleanliness, moisture levels, and chemical stability, EHC systems demonstrate more stable turbine control behaviour. Plants report a clear reduction in valve sticking and control drift, correlating directly with cleaner and more stable phosphate ester oil.
Keep your phosphate ester oil clean and stable
Protect turbine control performance with cleaner, drier, and more reliable EHC fluid.
No obligation. We start with an oil condition review to identify your improvement potential.
Phosphate ester oil
Extend the life and reliability of your phosphate ester systems
Phosphate ester oils are essential in electro-hydraulic control systems because they are fire resistant and allow turbines to react with precision. These fluids, however, are highly sensitive to moisture, oxidation, and chemical breakdown. Once contaminated, they lose resistivity, form acidic byproducts, and generate sludge that causes servo valve sticking and control drift.
Because phosphate ester fluids are costly to replace, maintenance managers face increasing operational risk when these degradation processes accelerate. CJC® Offline Filtration stabilises the fluid continuously, removing water, acids, varnish, and fine particles, so EHC systems remain reliable and turbine operation stays predictable.
What challenges phosphate ester fluids in turbine control systems
Steam and gas turbines operate under different conditions, but both expose lube oil to contamination that cannot be prevented by design alone.
High water affinity drives rapid degradation
Phosphate ester oils absorb moisture easily, reducing resistivity and destabilising EHC systems. Even small water increases accelerate hydrolysis and form acidic by-products.
Hydrolysis increases acidity and shortens fluid life
Heat and moisture cause chemical breakdown in phosphate ester oil. TAN rises, acids attack components, and oil life is shortened.
Varnish and sludge disturb servo valve operation
Oxidation residues form soft deposits that collect in tight valve clearances. This leads to sticky servo valves and unstable turbine control.
Contamination reduces electrical stability
Oil degradation lowers resistivity, affecting sensors and EHC stability. This increases the risk of control disturbances and unplanned shutdowns.
Centrifugal Separator
|
CJC® Filtration
| |
|---|---|---|
Energy Consumption
|
High (heating + rotating bowl)
|
Low (3% compared to Centrifuge)
|
Maintenance
|
Daily supervision required
|
Minimal, periodic filter change
|
Waste Generation
|
Several tonnes of sludge annually
|
Dry filter element only
|
Heating |
Required | None require |
CO₂ Impact
|
High (energy intensive)
|
Low (97% reduction)
|
Compliance |
Adds to CII |
Up to 2% CII improvement |
How it works
Outcome for turbine operators
Fewer servo valve sticking events
Cleaner oil keeps control valves operating freely, reducing sticking events and ensuring smoother, faster turbine response even during load changes.
Lower TAN progression
By slowing oxidation and acid formation, the fluid maintains its protective properties longer -extending oil life and reducing the need for corrective maintenance
Stable ISO cleanliness
Effective fine filtration maintains consistent cleanliness levels, even under high thermal stress, protecting sensitive components from wear and varnish deposits.
Reduced maintenance hours
Reliable oil quality lowers intervention frequency and enables more predictable control system performance, freeing maintenance teams to focus on critical tasks.
Clean Oil Is Not a Recommendation.
It Is a Reliability Strategy.
Understand contamination mechanisms, ISO codes, water control, and how to extend oil and component lifetime.
Where phosphate ester oil is used and how CJC® improves performance
Electro-Hydraulic Control (EHC) systems on steam turbines
Challenge: Moisture and oxidation residues cause servo valve sticking and unstable control.
Result: Cleaner, drier fluid with stable ISO codes and smoother valve response.
Generator brake and protection circuits
Challenge: Soft contaminants and water disturb fast-acting hydraulic components.
Result: Improved reliability of braking sequences and reduced wear on critical actuators.
Gas turbine hydraulic control and trip systems
Challenge: High temperatures accelerate oxidation and acid formation, raising TAN.
Result: Offline filtration reduces residues and slows TAN progression for better long-term stability.
Fire-resistant HFDR fluid systems
Challenge: These fluids are difficult to maintain with conventional inline filters, and degradation accelerates when moisture is present.
Result: Depth filtration removes ultra-fine particles, water, and sludge, helping preserve fire-resistant properties.
Documented performance in real turbine systems
Water content is reduced to safe EHC operating levels
Phosphate ester fluids absorb moisture easily. CJC® Offline Filtration reduces both free and dissolved water, allowing plants to bring the fluid back into the moisture range recommended by EHC system and turbine OEMs. Lower moisture slows hydrolysis and helps maintain electrical resistivity
TAN progression slows once water and oxidation products are removed
When hydrolysis is brought under control, the Total Acid Number stabilises. In documented EHC systems with rising TAN, CJC® filtration stopped the increase and allowed operation to continue without immediate fluid replacement.
Soft contaminants, varnish residues, and sludge are significantly reduced
Depth filtration with cellulose media removes oxidation byproducts that accumulate in tight valve clearances. Plants report restored actuator and servo valve performance once these soft contaminants are removed from the fluid.
System reliability improves as valve sticking incidents decrease
After restoring cleanliness, moisture levels, and chemical stability, EHC systems demonstrate more stable turbine control behaviour. Plants report a clear reduction in valve sticking and control drift, correlating directly with cleaner and more stable phosphate ester oil.
Evidence from phosphate ester oil systems worldwide
Improve Gearbox Reliability with Clean Oil
Clean gear oil is one of the easiest and most cost-effective ways to extend gearbox life, reduce downtime and keep operations running predictably. Start with an oil condition review and a practical filtration strategy tailored to your system.
No obligation, we start with a condition review and clear recommendations.