Oil Filter Testing
Southwest Research Institute (SwRI) characterizes oil, fuel, and hydraulic filter performance and integrity using a computerized fluid filter bench test facility. Testing determines filtering ability according to the various engineering specifications as well as specialized requirements for lubricant oil, hydraulic, and fuel filters of all sizes, including automotive, light- and heavy-duty diesel, and locomotive filters.
The Institute's 1,500-square-foot facility features versatile, computer-controlled emulated test systems for both Class A and Class B operations. This setup allows the differential pressure buildup across the test filter to be measured as contaminants are removed. The system's automated contaminant-additions handler provides a variable contaminant add-rate for selected compositions. The computer controls and monitors the temperature, safety features, automated sampling, and inlet, outlet, and differential measurement.
Virtual Instrument Concept
The filter test stand computer uses virtual instrument (VI) hardware control. The software technique replicates, on the computer, the appearance and function of the corresponding hardware. The operator trained to use the workbench apparatus can use the VI with no additional training. The VI display screen is familiar; an experienced operator will recognize all system controls. The computer-controlled systems provide preprogrammed test sequences to run, monitor, and terminate standard test formats automatically. Menu-driven programming allows operators to design and implement custom test parameters easily.
Precise Mass Flow
Combining computer control and data acquisition with Coriolis-based measurement instrumentation, SwRI precisely measures mass flow. Phase detectors and a powerful microprocessor supply basic measurements such as mass flow, density, and temperature.
Filtering Efficiency Rating
To determine filter efficiency, a special valve allows contaminants to flow directly into the test filter. To rate filter elements and filter assemblies easily, this test method determines percent filtering efficiency on a single pass basis for specific contaminant particle sizes or size ranges.
A submerged test filter is pressurized for the bubble/pore-size test, which determines the "bubble-all-over" point of test filters, measured in inches of water.
Samples of oils and hydraulic and transmission fluids are shaken vigorously to suspend minute particles. To determine "true cleanliness," a laser device counts and sizes particles for comparison to standard cleanliness levels. To determine the effectiveness of the test filter, the true cleanliness of sample fluids is measured before and after the filter test.
Oil Filter Test Stand
The Institute's multifunctional test facility simultaneously accommodates three different filters with differing flow rates in a single cabinet. The system tests oil, hydraulic, and fuel filters. All configurations meet SAE J806 specifications and can be modified for custom evaluations.
For almost 15 years, the Institute has conducted oil filter testing according to SAE standards, continually improving capabilities and facilities. Experience includes:
The Institute tests spin-on or cartridge-type automotive, diesel, and locomotive filters and all sizes of lube oil, hydraulic, or fuel filters for a variety of contaminants. Flow rates from 0.5 to 60 gpm are tested at up to 250° F. Various contaminant injection systems, such as multi-pass injection and quadrant delivery, are investigated.
The Institute has an international reputation for the quality,
consistency, and reliability of its tests.