scope:

This International Standard specifies a procedure for evaluating the pressure drop versus flow characteristics of industrial oil hydraulic filters and provides a basis of agreement between the filter manufacturer and user. Two standards of measurements are specified: a) Class A - For accurate evaluation for referee purposes - requiring laboratory conditions. b) Class B - For evaluation for general purposes - requiring test facilities less stringent that laboratory conditions. This International Standard specifies the method of measuring the pressure drop across a hydraulic fluid filter under various conditions of flow.