Meaning
Chemical breakdown in hydraulic transmission fluids occurs when sustained thermal or mechanical loads alter the molecular structure. This fill oil degradation reduces the ability of the fluid to transmit force or lubricate the moving parts of a sensor. It leads to the formation of sludge and acidic compounds that can corrode the internal surfaces of the instrument.
Maintaining the quality of the fluid is necessary for the accurate transmission of pressure signals in subsea environments.
Oxidation Rate
High temperatures accelerate the reaction between the oil and any trapped oxygen or moisture. During the fill oil degradation process, the viscosity of the fluid changes, which alters the response time of the connected equipment. Regular sampling of the oil helps in identifying the onset of this chemical change before it affects the performance of the system.
Signal Distortion
Thickened or contaminated oil prevents the smooth movement of the internal components. When fill oil degradation occurs in a pressure transmitter, the resulting readings may become sluggish or show an offset from the true value. Correcting these errors in the field is difficult without a full replacement of the fluid.
Maintenance Trigger
Automated alerts signal the need for a service when the dielectric constant of the oil reaches a certain threshold. Replacing the fluid at the first sign of fill oil degradation prevents long term damage to the seals or bellows. Detailed logs of the oil condition provide a history of the stress levels experienced by the device.
Most high precision instruments use synthetic oils to minimize these risks and extend the interval between calibrations.
