The SAE Recommended Practice specifies a standardize method and test procedure to measure low pressure differential (< 1bar) brake component brake fluid flow performance. The standard can be utilized for flow measurements across hydraulic brake components such as master cylinders, apply system to chassis controls piping, or other sources of flow restriction in the low pressure side of the hydraulic brake system. It covers materials, manufacturing processes, and general properties required to meet the wide range of service encountered in automotive application. This specification covers only low pressure differential fluid flow and does not include measurement recommended practice for High Pressure differential (> 1 bar) flows.
The purpose of this recommended practice is to provide a standardized set of test conditions, methodology, data processing, and reporting for the measurement of fluid flows across brake hydraulic components. This recommended practice addresses these topics for the low pressure differential regime (defined as below 1 bar pressure differential, as typical on the feed side of a hydraulic pump).
Below are noted key points in the rationale used by the founding task force to set the parameters in this recommended practice:
Every effort was made to give the user flexibility to define the test specimen (as a component or subsystem comprised of multiple components) according to the measurement needs, but provide enough structure to ensure repeatable measurements from lab to lab. It is critical that a clear definition of the test specimen be determined before the test and documented with the test results.