BS ISO 26867:2009

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols and abbreviated terms
  4.1 Symbols
  4.2 Abbreviated terms
5 Test conditions and preparation
  5.1 Inertia for the front axle
  5.2 Inertia for the rear axle
  5.3 Test wheel load
  5.4 Pressure ramp rate
  5.5 Maximum pressure
  5.6 Pressure level with no power assist
  5.7 Sampling rate
  5.8 Initial brake temperature
  5.9 Brake warm-up
  5.10 Temperature measurement
  5.11 Brake fluid displacement measurement
  5.12 Cooling air conditions
  5.13 Cooling air velocity or volume
  5.14 Conditioning settings for temperature and absolute
       humidity (humidity ratio)
  5.15 Dynamometer rotational speed between brake
       applications
  5.16 Orientation of brake set-up
  5.17 Direction of air concerning brake set-up
  5.18 Brake cooling rate
  5.19 Wear measurement
  5.20 Lateral run-out
  5.21 Rotor or drum condition
  5.22 Fade sections
  5.23 Data collection
6 Test procedures
  6.1 Test procedure for product monitoring with no optional
       brake applications
  6.2 Test procedure for product development with additional
       brake applications
  6.3 Standard friction values calculated during test
       procedure
7 Test report
  7.1 General
  7.2 Graphical report
  7.3 Tabular data for each brake application
  7.4 Wear measurements
  7.5 Test conditions
  7.6 Cooling air conditions
  7.7 Brake cooling rate
  7.8 Friction values
  7.9 Statistical analysis
Annex A (informative) - Sample report for disc brakes
Annex B (informative) - Histograms for instantaneous friction
                        values
Annex C (informative) - Reference calculations for cooling air
                        speed and flow
Bibliography

Defines a test procedure for assessing the influence of pressure, temperature, and linear speed on the coefficient of friction of a given friction material in combination with a specific mating component (rotor or drum).

This International Standard describes a test procedure for assessing the influence of pressure, temperature, and linear speed on the coefficient of friction of a given friction material in combination with a specific mating component (rotor or drum).

This International Standard is intended for use when comparing friction materials under the same conditions, or when controlling friction behaviour against a specification or certain performance limits. In order to take into account the different types of dynamometer cooling systems and to ensure repeatable temperature increments, the brake temperature is the control item during the fade sections. The types of brakes and discs used will vary according to individual projects.

Production verification testing can use the results from this test in conjunction with a statistical process control system as part of a quality assurance plan. The specific project or programme will detail the applicable limits and assessment criteria.

This International Standard also allows for additional sections and brake applications that can prove useful during product development testing.