AS ISO 8925:2021 Earth-moving machinery一Diagnostic ports.
3.2 Flow measurement ports
Flow measurement ports shall be adequate for the flow to be measured. Generally, sizes below 25 mm tube should be as specified in ii and sizes equal to and above 25 mm should have either threaded or flanged port faces.
4 Application guidelines
4.1 Number and location of diagnostic ports
The number and location of diagnostic port checking points shall be determined by the manufacturer and shall be commensurate with the complexity of the system being checked and cost effectiveness.
The preferred location of diagnostic ports is in the component; however, they should be readily and safely accessible which might often require them to be located in a connecting line. The ports should be so located in the fluid stream as to minimize any conditions which could cause inaccuracies in readings for fluid sampling, the ports should be located in a turbulent flow section of the system.
The ports shall be fitted with devices to prevent loss of fluid during connecting and disconnecting of diagnostic measuring instruments. The ports shall also be located so that the fluid is not contaminated from the surface of the machine when connecting the measuring instruments or during fluid sampling.
4.2 Accessibility
4.2.1 Test ports shall be accessible with common tools, limited to those specified in ISO 4510-1, without the removal of any component other than sealing caps, access panels and/or plates.
4.2.2 A free access area of 75 mm radius around the centreline of the port and 200 mm from the port surface shall be provided. Access to the port shall be as specified in ISO 2860.AS ISO 8925 pdf download.