GB/T 14172-2021Bench test methods of static roll stability for motor vehicles, trailers and combination vehicles (English PDF)

4.2 Roll test bench

4.2.1 The maximum roll angle of the test bench surface shall be able to meet the static roll stability requirements of the vehicle under test. The roll angle of the test bench shall be able to be adjusted continuously between zero degrees and the maximum roll angle, and can be fixed at any angle.

4.2.4 The flatness of the test bench is not lower than the tolerance level 12 specified in Table B.1 of GB/T 1184-1996.The parallelism between the longitudinal axis of the test bench and the centerline of rotation shall not be lower than the tolerance level 12 specified in Table B.3 of GB/T 1184-1996.

4.3 Anti-skidding block In order to prevent the vehicle from skidding during the test, an anti-skidding block can be installed on the roll test bench. The height of the anti-skidding block is set to minimize the impact on the test results.

4.4 Anti-rollover safety equipment Special safety equipment to prevent the vehicle from overturning accidents shall be equipped during the test.

5.1 Vehicle conditions

5.1.1 Tires In the test load state, the cold inflation pressure of the test vehicle's tires shall meet the vehicle manufacturer's regulations.

5.1.3 Vehicle preparation All vehicle assemblies, components and auxiliary equipment (including tools and spare tires) shall be fully equipped according to the manufacturer's regulations and installed in the prescribed positions. As for the assembly or component whose position can be adjusted (such as lifting shaft, adjustable air suspension), it shall be adjusted to a state suitable for the load.

5.2 Environmental conditions In the outdoor test, the ambient wind speed shall not exceed 5m/s, and the lateral wind speed shall not exceed 3m/s.

5.3 Special requirements for trailers

5.3.1 Semi-trailers Semi-trailer measurement shall be carried out in the form of a combination of tractor or tractor simulation device. The tractor simulation device shall have structural characteristics similar to the actual tractor. The structure and height of the tractor seat of the tractor (or tractor simulation device) shall match that of the semi-trailer.

5.3.2 Tow bar trailer and central axle trailer A tractor, tractor simulation device or other supporting device shall be used to assist in the test. The structure and height of the connecting device used on the tractor, tractor simulator or other supporting device shall match the tested trailer.

6.1.1 Measure the maximum stable roll angle when the vehicle leans to the left

6.1.1.1 Place the vehicle on the roll test bench. The tires are driving in a straight line. The longitudinal symmetry plane of the vehicle is parallel to the centerline of rotation of the test bench.

6.1.1.2 Implement the parking brake. The transmission is in neutral position (when applicable). The differential lock is in an inactive state. Install anti- skidding block and anti-rollover safety equipment.

6.1.1.5 Drive the vehicle away from the roll test bench and park again according to the requirements of 6.1.1.1.

6.1.1.6 Repeat the provisions of 6.1.1.1~6.1.1.5.The test is carried out three times in total.

6.1.1.7 If the maximum difference between the three measurements exceeds 0.6°, the number of tests shall be increased until the maximum difference between the three consecutive measurements does not exceed 0.6°. It shall be based on the last three measurements.

6.1.2 Measure the maximum stable roll angle when the vehicle leans to the right Repeat the test steps in 6.1.1.Measure the maximum stable roll angle when the vehicle leans to the right.

6.2.1 Judgment test of the stable roll angle when the vehicle leans to the left

6.2.1.1 Test according to 6.1.1.The vehicle will stop when it leans to the left with the test bench to the value of theta (if it reaches the critical state of rollover before the value of theta, it shall stop). The test is repeated three times.

6.2.2 Judgment test of the stable roll angle when the vehicle leans to the right Repeat the test steps in 6.2.1.Determine the stable roll angle when the vehicle leans to the right.

6.2.3 Result judgment According to the test results of 6.2.1~6.2.2, if a certain angle theta is the stable roll angle when the vehicle rolls to the left (or right), it can be determined that the maximum stable roll angle when the vehicle rolls to the left (or right) is not less than theta.