BS ISO 23671:2015 pdf download

BS ISO 23671:2015 pdf download

BS ISO 23671:2015 pdf download.Passenger car tyres — Method for measuring relative wet grip performance — Loaded new tyres
1 Scope
This International Standard specifies the method for measuring relative wet grip braking performance index to a reference under loaded conditions for new tyres for use on passenger cars on a wet-paved surface.
The methods developed are meant to reduce variability. The use of a reference tyre is necessary to limit the variability of the testing procedures.
This International Standard applies to all passenger car tyres.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 4000-1, Passenger car tyres and rims — Part 1: Tyres (metric series) ASTM E303-93 (Reapproved 2013), Standard Test Method for Measuring Surface Frictional Properties Using the British Pendulum Tester
ASTM E501-08, Standard Specification for Standard Rib Tire for Pavement Skid-Resistance Tests
ASTM E965-96 (Reapproved 2006), Standard Test Method for Measuring Pavement Macro texture Depth Using a Volumetric Technique
ASTM E1136-93 (Reapproved 2003), Standard Specification for A Radial Standard Reference Test Tire
ASTM F2493-08, Standard Specification for P225/60R16 97S Radial Standard Reference Test Tire
EN 13036-1, Road and airfield surface characteristics — Test methods — Part 1: Measurement of pavement surface macrotexture depth using a volumetric patch technique
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 test run
single pass of a loaded tyre over a given test surface
3.2 candidate tyre
<set> test tyre (set) that is part of an evaluation programme
3.3 reference tyre
<set> special test tyre (set) that is used as a benchmark in an evaluation programme
Note 1 to entry: These tyres usually have carefully controlled design features to minimize variation.
Note 2 to entry: See ASTM F2493-08 — P225/60R16.
Effects of slider pad wear: The pad shall be removed for maximum wear when the wear on the striking edge of the slider reaches 3,2 mm in the plane of the slider or 1,6 mm vertical to it in accordance with ASTM E303-93 (Reapproved 2013), 5.2.2 and Figure 3. Checking track surface BPN constancy for the measurement of wet grip on a standard vehicle: To decrease the dispersion of test results, the BPN values of the track should not vary over the entire stopping distance. The operation shall be repeated five times at each point of the BPN measurement. The BPN shall be measured every 10 m on the braking lane and the coefficient of variation of the BPN averages shall not exceed 10 %.