Detail of GB/T 41327-2022

Introduction of GB/T 41327-2022

Test method for measuring ice grip performance of passenger car tyres 1 Scope This document specifies the test method for measuring the grip performance of passenger car tyres on ice roads. It includes test conditions, test steps, data processing, test and test report of using reference tire to test ice ground performance. This document is applicable to car radial tire. 2 Normative References The contents in the following documents, through normative references, constitute indispensable provisions of this document. Where, for dated references, only the version corresponding to that date applies to this document; For undated references, the latest version (including all amendments) is applicable to this document. GB/T 6326 Tyre Terms and Definitions GB/T 33829 Test Method for Snow Grip Performance of Passenger Car Tyres 3 Terms and definitions The following terms and definitions defined in GB/T 6326 and GB/T 33829 are applicable to this document. 3.1 Ice grip index The ratio of ice grip index IG test tire to standard Huai test tire. 3.2 Discontinuous test Non consecutive sequence The test sequence is performed after the ice pavement is reconditioned, or on different test roads, or on different dates. 4 Test conditions 4.1 Pavement conditions 4.1.1 The test ice pavement shall be flat and smooth, the length and width shall meet the requirements of relevant tests in this document, and the gradient shall not be greater than 2%. 4.1.2 Pre grinding shall be carried out before the test. If drinks are needed, they should be completed 1h before the test. The water used to prepare the ice surface shall be clean. Before the test, the braking circuit shall be simulated with non test tyres until the friction force becomes stable. 4.1.3 225/60R16 98S standard test tire shall be used to measure the grip on ice road. The average deceleration of each test run in shall be kept between 0.97 m/$° and 1.72 m/s -. 4.2 Climatic conditions 4.2.1 The ambient temperature range measured at about 1m above the ice pavement is - 21 ° C~4 ° C; The temperature range of ice pavement is - 21 ° C~- 5 ° C. The maximum relative humidity of the test environment shall be less than 90%. 4.2.2 During the test, try to avoid direct sunlight and large changes in sunlight or humidity, and the wind speed should not be greater than 5m/s. 4.3 Test vehicle conditions 4.3.1 Select the test vehicle with good vehicle condition and ABS system that is suitable for both test tyres and standard test tyres. 4.3.2 The test vehicle shall be equipped with calibrated sensors suitable for measurement under cold and freezing conditions. The speed and distance data acquisition system has the function of storing measurement results. The accuracy of the sensor and system shall meet: the relative uncertainty of the measured or calculated fully developed average deceleration shall be less than 1%. 4.3.3 The test vehicle shall be produced in continuous batches without any modification affecting braking characteristics, and the load capacity of each wheel shall meet the requirements for test load of test tire. If the tire load needs to be increased, the vehicle can be counterweighted. 4.4 Test measuring instruments 4.4.1 Test measuring instruments shall be insensitive to vibration, deceleration and environmental temperature changes, and all exposed parts shall be able to withstand 100% relative humidity, dust, impact, vibration and other adverse factors. 4.4.2 The speed of the test vehicle shall be measured by installing GPS and other non-contact speed measuring instruments. Within the range of - 21 ° C~4 ° of ambient temperature, the maximum allowable error is: a) vehicle speed measurement: ± 0.5 km/h; b) Distance measurement: ± 0.1 m. 4.4.3 During the test, the actual vehicle speed measured by the measuring instrument or the difference between the actual vehicle speed and the standard vehicle speed shall be displayed in the vehicle so that the driver can adjust the vehicle speed in time. 4.4.4 The accuracy of the barometer shall be ± 5kPa.

Contents of GB/T 41327-2022

1. Scope…………………………………………………………………………… 2. Normative reference …………………………………………………………… 3. Terms and definitions…………………………………………………………… 4. Pavement conditions…………………………………………………………… 5. Test procedure…………………………………………………………………… 6. Data processing………………………………………………………………… 7. General……………………………………………………………………………