Flow Meter Ideal for SAE Brake Testing Standard
In January 2012, the Society of Automotive Engineers (SAE) initiated a project to develop a standard for the testing of: Brake Component Hydraulic Flow Rate Measurement. This new standard will be researched and issued through the SAE committee for Hydraulic Brake Components Standards.
The scope of their work will include; a proposed new standard to define test conditions and procedures for measuring the flow rates across hydraulic brake components such as chassis controls modules, banjo connections, brake hoses, and other sources of flow restriction in a hydraulic brake system. The scope will include low pressure differential (e.g. suction into a fluid pump) and high pressure differential (e.g. step apply, stopping distance test) conditions.
The reason that such a standard has been proposed is that flow rates of brake fluid through hydraulic brake components affect the ability of the brake system to respond to driver and control inputs. It affects the ability of the chassis controls pump to fill itself, and of the system to generate a quick pressure response during a forceful brake apply from the driver. There is often a number of different brake suppliers providing components for a vehicular brake system, but currently there is no industry standard method of measure flow rates through them. An industry standard specification will allow meaningful comparison and specification of flow rates, which in turn will allow accurate system response modeling during initial system design, and accurate diagnosis of performance issues related to flow rate during development. The proponents of this new standard believe as well that with the added functionality being demanded of the brake system (supporting active cruise control and autonomous braking) and new technologies being added (electric apply systems) that it will be more important than ever to understand flow rates throughout the hydraulic brake system (and its impact on system performance).
We at Max look forward to working with SAE and the various manufacturers within the brake component industry to establish reliable expectations in resolution, repeatability and response time in the flow measurement tests. Max has a long history of supplying small flow rate meters with high pressure capabilities and 1000 pulse/ml resolution for this exact purpose. Bi-directional encoding and sophisticated detection of rotation give Max meters the ability to offer zero crossing capability without suffering from dither and spurious pulse generation. Please refer to the Max Model 213 meter and Model 295 transmitters for further details.
