Fire-Resistant Hydraulic Fluid
Water-containing and synthetic fluids for circuits near heat or ignition sources, in steel and foundry work, glass plants and underground installations.
Features
- Water-containing fluids limit working pressure and pump speed and usually require a de-rated pump selection rather than the one already fitted.
- Water-free synthetic fluids carry higher pressures but are more selective about seal and paint compatibility.
- Water content in water-containing types has to be monitored and corrected in service, since evaporation changes both fire resistance and lubricity.
- Converting an existing mineral-oil system means flushing, changing seals and filters, and confirming the pump's de-rated capability first.
- Disposal and site handling rules differ from mineral oil and have to be settled before the first delivery.
Specifications
| Figure | Typical range | Unit | Why it matters |
|---|---|---|---|
| Fluid class | water-glycol / synthetic ester / water-in-oil | each class has its own pump and seal limits | |
| Viscosity at 40 degrees C | 46 | mm2/s | compared against the pump's window as de-rated |
| Water content | 35 - 45 where applicable | % | both fire resistance and lubricity depend on it |
| Seal compatibility | nitrile yes, some elastomers no | a conversion can fail on seals rather than on pumps |