Hydraulic Oils

Biodegradable Hydraulic Fluid

Saturated and unsaturated ester fluids for machines working over water, in water catchment areas, on flood defence work and in forestry.

Features

  • Chosen where a hose failure would put fluid into water or protected ground, which is often a condition of the contract rather than a preference.
  • Saturated esters tolerate heat and moisture better than vegetable-based fluids and last considerably longer in service.
  • Moisture control is essential, because water promotes hydrolysis and the fluid degrades from the inside without looking different.
  • Conversion from mineral oil needs flushing and a seal and hose review, since residual mineral oil above a few percent undermines the biodegradability claim.
  • Fluid condition is monitored by sampling; the useful life is shorter than mineral oil and has to be planned for.

Specifications

Figure Typical range Unit Why it matters
Ester type saturated synthetic ester decides thermal and moisture tolerance
Viscosity at 40 degrees C 46 mm2/s matched to the pump as with mineral oil
Residual mineral oil after conversion below 2 % above this the environmental claim no longer holds
Water content limit 0.1 maximum % water drives hydrolysis of the ester