BS ISO 10191-2021 pdf free download – Passenger car tyres — Verifying tyre capabilities — Laboratory test methods
4 Test equipment and conditions
4.1Test drum, cylindrical driven flywheel (drum) having a diameter of 1,7 m± 1 % or 2,0 m± 1 %.The surface of the drum shall be smooth steel.For the endurance test and low-pressure performancetest according to 7.1, the drum may be coated with a thin layer of non-stick material，,e.g.polytetrafluoroethylene (PTFE), to eliminate parasitic tread block chunking (PTBC), provided thatthe total drum diameter remains within above limits. The width of the test surface and, if applicable,the width of the thin layer of the non-stick material shall be equal to or exceed the overall width ofthe test tyre.
When PTFE lubricant is used as non-stick material, care shall be taken that the composition of thelubricant is suitable for use with rubber compounds. For example, silicone-oil-based lubricants withPTFE content between 40 % and 55 % have shown appropriate performance for this purpose.
For the test drum, the loading device shall have a capacity of at least 1 000 kg and the accuracy shall bewithin ±1 % of the full scale. The speed capability of the equipment shall be adequate for therequirements of the test methods. The accuracy of the test drum speed shall be within% km/h.
4.2 Inflation pressure gauges,with a maximum scale value of at least 500 kPa and an accuracywithin ±5 kPa.
4.3 Conditioning and test room temperature: lf a tyre manufacture desires to increase testseverity, tyre conditioning and the tests may be carried out at a higher temperature than specified in therespective subclauses.
5 Testing of tyres with diagonal or bias-belted structure and of T-typetemporary-use spare tyres
5.1 Endurance test
5.1.1 Preparation of tyre
5.1.1.1 Mount the tyre on a test rim and inflate it to the pressure specified in Table 1.
5.1.1.2 Maintain the tyre and rim assembly at an ambient temperature of not less than 35 C forat least 3 h.
5.1.2Test procedure
5.1.2.1 Readjust the inflation pressure to the value specified in Table 1 immediately before testing.
5.1.2.2 Mount the tyre and rim assembly on a test axle and press the tyre radially against the outer faceof the test drum.
5.1.2.3 During the test, the ambient temperature, at a distance of not less than 150 mm and notmore than 1,0 m from the tyre, shall be at least 35 °C.No provision shall be made for cooling the tyreduring the test.
5.1.2.4 Conduct the test, without interruptions, at not less than 80 km/h test speed with loads and testperiods not less than those shown in Table 2.
5.1.2.5 Throughout the test, the inflation pressure shall not be corrected, and the test loads shall bekept constant at the value corresponding to each test period.
5.2 High-speed test
5.2.1 General
For those tyres not marked with a service description, note should be taken of the additional testconditions given in Annex A.
5.2.2Preparation of tyre
5.2.2.1 Mount the tyre on a test rim, inflate it to a pressure related to its speed symbol, tyre versionand load type, as shown in Table 3.
ln exceptional cases, a different test inflation pressure may be used. In such a case, the tyre shall beinflated to that pressure.
5.2.2.2 Maintain the tyre and rim assembly at test room temperature for at least 3 h.
5.2.3 Test method
5.2.3.1 Before or after mounting the tyre and rim assembly on a test axle, re-adjust the inflation pressure to that specified in 5.2.2.
5.2.3.2 Press the tyre and rim assembly against the outer face of the test drum.
5.2.3.3 Apply a load to the test axle according to Table 4.BS ISO 10191 pdf download.