GCC STANDARDIZATION ORGANIZATION (GSO)

Transcription

1 هيئة التقييس لدول مجلس التعاون لدول الخليج العربية GCC STANDARDIZATION ORGANIZATION (GSO) مشروع مواصفة نهائي Final Draft of Standard FDS TC 02/SC 01 إعداد اللجنة الفنية الفرعية الخليجية رقم Prepared by GSO Technical Sub-Committee No. TC 02/SC 01 GSO 02 /01/FDS/ 1784:2018 إطا ارت سيا ارت الركوب طرق اختبار درجة مقاومة اإلطار للح اررة Passenger Car Tyres: Methods of Testing of Tyre Temperature Resistance Grading ICS: This document is a draft Gulf Standard circulated for comments. It is, therefore, subject to alteration and modification and may not be referred to as a Gulf Standard until approved by GSO. هذه الوثيقة مشروع لمواصفة قياسية خليجية تم توزيعها إلبداء ال أري والملحوظات بشأنها لذلك فإنها عرضة للتغيير والتبديل وال يجوز الرجوع إليها كمواصفة قياسية خليجية إال بعد اعتمادها من الهيئة.

2 تقديم هيئةة الوطنيةةة التقيةي بواسطة لجا لةدو فةة الةةدو التعةاو مجلة األعضةةاء فنية متخصصة. ومةةن لةدو مهةةا الخلةي الهيئةةة إقليميةة هيئةة العربيةة إعةةداد المواصةةفات فة تضةم القياسةةية عضةويتها أجهة واللةةوا ا الفنيةةة التقيةي الخليجيةةة قةةةر المجلةةة الفنةةة لهيئةةةةة التقيةةةي لةةةدو مجلةةةة التعةةةاو لةةةدو الخلةةةي العربيةةةةة فةةة اجتماعةةة قةةةةةةم ( ) الةةةةةةةةةذي عقةةةةةةةةةد بتةةةةةةةةةا ي.../.../... هةةةةةةةةةة الموافةةةةةةةةة/.../.../... اعتمةةةةةةةةةاد تحةةةةةةةةةدي الال حةةةة الفنيةةةة الخليجيةةةة قةةةم " إطةةةا ات سةةةيا ات الركةةةو طةةةر اختبةةةا د جةةةة مقاومةةةةةة اإلطةةةةةا للحةةةةةة ار " التةةةةة تةةةةةم د اسةةةةةةتها و إعةةةةةدادها ضةةةةةةمن برنةةةةةام عمةةةةةل اللجنةةةةةةة الفنيةةةةةة الفرعيةةةةةةة الخليجيةةةة قةةةم " TC 02/SC01 اللجنةةةة الفنيةةةة الفرعيةةةة الخليجيةةةة لمواصةةةفات المركبةةةات واإلطةةةا ات " المد جة ف خطة دولة الكويت. على أ تلغ الال حة الفنية الخليجية الخليجية قم GSO 1784:2006 و تحل محلها. 2

3 Passenger Car Tyres Methods of Testing of Tyre Temperature Resistance Grading 1- SCOPE AND FIELD OF APPLICATION This standard is concerned with the methods of testing of tyres for temperature resistance grading. 2- COMPLEMENTARY REFERENCES 2.1 GSO 1783 Motor Vehicles Tyres - Treadwear, Traction and Temperature Resistance Grading. 2.2 Gulf standard which will be approved by GSO concerned with Passenger Car Tyres - Methods of Testing of Tyre Treadwear. 2.3 Gulf standard which will be approved by GSO concerned with Passenger Car Tyres - Methods of Testing of Tyre Traction Grading. 3- VISUAL INSPECTION Tyres shall be visually inspected to check the following: 3.1 The absence of any cracks or cuts in the tread or on sidewalls, and ensures it is free from any metal pieces, gravel or other foreign matter pinched or stuck in the tyre. 3.2 Information marked on the tyre such as treadwear grade, traction and temperature grade. 3.3 Date of manufacture. 3.4 Country of manufacture. 4- MEASURING INSTRUMENTS 4.1 Time measuring instruments: It shall permit measurements of time to an accuracy of (± 0.001) second. 4.2 Temperature measuring instruments: It shall permit measurements of temperature to an accuracy of (± 1 o C). 4.3 Pressure measuring instruments: Pressure dial gauges to an accuracy of ± 2 kpa. 3

4 5- TEMPERATURE RESISTANCE GRADING 5.1 Preparation of Tyre The tyre shall be mounted on the rim and inflate it to the applicable pressure specified in Table 1 shown below The tyre and the rim assembly shall be conditioned to a temperature of 38 o C to 44 o C and not less than 38 o C for at least 3 hours The tyre pressure shall be adjusted again to the applicable inflation pressure specified in the table Apparatus A flat-faced steel drum in diameter and at least the same width as the section width of the tyre to be tested A test room controlled at a temperature not less than 38 o C during the test period Temperature sensors. 5.2 Test Procedure The tyre rim assembly shall be mounted on the test axle. TABLE (1) Test Inflation Pressures Test Type Tyres other than CT tyres CT Tyres PSI kpa kpa Treadwear test Temperature resistance test The tyre tread shall be pressed against the surface of a flat-faced steel test wheel that is (1.7 m) in diameter and at least as wide as the section width of the tyre The temperature sensor shall be located so that its readings are not affected by heat radiation drafts, variations in the temperature of the surrounding air or guards or other devices During the test the inflation pressure (Table 1) and the temperature of the ambient air measured at (300 ± 2) mm from the edge of the rim flange 4

5 at any point on the circumference on either side of the tyre be maintained as indicated in item Then pressed the tyre against the test wheel with a load of 88% of the tyre s maximum load rating as marked on side wall The test wheel shall be rotated at 250 rpm for two (2) hours Remove the load, allow the tyre to cool to temperature not less than 38 o C or for 2 hours, whichever occurs last and readjust the inflation pressure shall then be readjusted to the initial pressure specified in Table inflation pressure shall then be readjusted to the initial pressure The test shall be continued with the load applied and without interruption or readjustment of inflation pressure, with the test wheel rotation at 375 rpm for 30 minutes at the end of 30 minutes increases the rotation of the test wheel by another 25 rpm for another 30 minutes Increase the rotation by 25 rpm every 1/2 hour until the tyre has run at 575 rpm for 30 minutes or to failure whichever occurs first. 5.3 Result The tyre shall be checked for evidence of bead separation, tread chunking, broken cords, cracking or open splices after every test at 250 rpm, 375 rpm, 400 rpm, until 575 rpm The tyre shall be graded C if it fails to complete the 500 rpm test The tyre shall be graded B if it successfully completes the 500 rpm test The tyre shall be graded A if it successfully completes the 575 rpm test The temperature grade for this tyre is established for a tyre that is properly inflated and not overloaded. Excessive speed, underinflation, or excessive loading, either separately or in combination, can cause heat buildup and possible tyre failure. 5

6 REFERENCES: 1) FMVSS No. 104 Uniform tire quality grading standards