Purpose
This test procedure permits the evaluation of the ralative filterability of lubricants and hydraulic oils.
Brief description of the method
In this method (ISO 13357), up to 3 litres of the fluid to be tested are passed through 3µm filter medium at a temperture of 62.7°C and a constant flow rate of 20 ml/min. The test is terminated when a pressure of 25 psi (.7 bar) across the filter medium is reached.