Water Saturation of Quintolubric 888® Fluids
Water contamination in hydraulic fluids can cause numerous problems for the components of the hydraulic system as well as for the fluid itself. A system in operation will keep the water well dispersed, but at stagnant locations, water will collect at the bottom of components such as the reservoir, cylinders, cooler, accumulators, pump housings and valve bodies. Under these conditions, pure water can be present and metal parts can be quickly damaged by corrosion. Over an extended period, the water and hydraulic fluid can react at higher temperatures causing excessive amounts of fatty acid material leading to fluid degradation.

This corrosion and fluid degradation requires the presence of "free water" meaning an amount in excess of that which can be dissolved in the fluid. We call the maximum amount of dissolved water at a certain temperature the "saturation point." Water saturation points differ for different fluid chemistries. Please find below the water saturation points for QUINTOLUBRIC 888 fluids at various temperatures. The graph shows the values for QUINTOLUBRIC 888-46 and QUINTOLUBRIC 888-68.

At room temperature, the saturation point is around 0.2% moisture. Above that amount, free water can start causing operational problems. Therefore, we recommend that moisture levels be kept below 0.2% and preferably below 0.1% in order to build a margin of safety before free water can form.

This information is being provided in order to aid customers that are implementing water monitoring systems.