Major Aviation Engine Manufacturer Case Study

Issue: An aircraft turbofan engine manufacturer has multiple inertial welders which are driven by hydraulic systems. All of the welders had dedicated OEM oil filtration systems installed on them to remove water and contaminants. However, oil contamination levels were high and trace amounts of water were still present. Periodically, they would have issues with the servo valves, which due to age of the equipment, would often take months to repair. In addition to the repair costs, the welder OEM also recommended that all of the oil be changed each year.

Solution: We first did a detailed survey of all of the welders including filters type and filter change frequency and compared that information to their internal documents. Additionally, we reviewed the history of the oil analyses. In general, the ISO goals of the oil were not being met.

We recommended installing a Como Model 265 dedicated filter system with dual housings on each of the welders and running them 24/7 in a kidney loop fashion. Three months after the installation, we inspected each filtration system for proper operation and then obtained oil samples and had them tested for particles, percent water and viscosity.

The results of the oil analysis showed that the quality of the oil had improved dramatically. Due to the prior levels of original contamination, we recommended replacing the filters at that time. The client was so pleased that they asked us to come back in 12 months and test again. Follow up yearly particle counts, water, and viscosity numbers were excellent with the oils in the units meeting a cleanliness ISO goal of 15, 13, 10. As a result of the quality of the oil analysis, the yearly oil changes were suspended.

Six years into this program, the servo valves no longer fail due to oil quality related issues. Some oil has been changed due to heat exchanger failures and other mechanical issues but it has not been changed for oil quality related issues. And, since they are not automatically changing oil each year, the company has prevented unnecessary down time, offset the purchase of 40,000 gallons of high-quality hydraulic oil and saved an estimated $500,000!