WIXOM, Mich.—Hallite Seals Americas Inc. and the Milwaukee School of Engineering's Fluid Power Institute has developed a test method to protect hydraulic systems from dirt and dust.
The test better measures the amount of harmful contamination that enters a typical hydraulic system through the rod wiper, measuring dry particles attributed to being a major cause of hydraulic system inefficiency, degradation and failure.
Hallite said no International Organization for Standardization (ISO) method exists for testing a rod wiper's ability to prevent four, six and 14 sized micron particles from entering the hydraulic system, which according to ISO 4406 are the three most damaging to the system.
Hallite partnered with MSOE to attempt to fix that. The firm provided insight for the school to develop the test fixture, rig and develop the procedure. The two took an SAE International standard, J1195, as a baseline and in eight months developed the new procedure.
“Pretty much in the industry right now there is no standard rod wiper test,” Business Development Manager Chuck White said. “Even though there was SAE, nobody ever used it. It's very old and wasn't directed specifically at hydraulics I would say. It was more for power steering and not accepted as a standard rod wiper test.”
One key element Hallite wanted to improve upon was to identify specifically the particle sizes contaminating the system. White said the SAE standard utilized gravimetric measuring, or the weight of the oil, to determine how much contamination was coming by the rod wiper. That process determines the weight of the oil before and after the test but does not specifically identify how much of that contamination truly is threatening to the system.
Hallite's test uses particle counting, only counting particles that would be sizes that are deemed by ISO 4406 as detrimental to the system—those that would affect control valves, pumps, motors and filters.
“The SAE spec was all right, but we used it as a basis and made some significant modifications and created this new standard that tells us so much more about the particles getting into the system that will harm the system,” White said.
While not an industry standard yet, White hopes the test gains traction in the industry as establishing a more universal baseline.
“This gives us a measurable method to prove whether or not we're better and gives us a standard to measure how much better we are when we do make improvements,” White said.
Hallite already has utilized the test on its Hallite 820 rod wiper, showing its improvements from the old Hallite 520 at the IFPE show in March 2014 at Las Vegas. White said the 820 has performed very well on the market so far and provides better protection against ingression.
“With this testing, we were able to establish our baseline and show that our 820 performed much better than our 520,” he said. “That was huge to be able to show with data.”
Hallite manufactures high performance hydraulic sealing products from its headquarters in Wixom. It is a member of the Fenner P.L.C. group of companies.