GB/T 5909-2021Commercial vehicles - Wheels - Performance requirements and test methods for cornering and radial fatigue (English PDF)

3.1 wheel-tire assembly

an assembly made up of wheels, tires and valves

3.2 crack

the material separation that occurred during the test expanded to 3mm and above where, µ - The set friction coefficient between tire and road surface, see Table 1;

R - The tire static load radius is the maximum tire static radius specified by the vehicle or wheel manufacturer to be used on the wheel, in meters (m);

d - The internal or external offset of the wheel (the internal offset is positive and the external offset is negative), in meters (m); If the wheel uses both internal offset and external offset, the internal offset is used;

Fv - The rated load on the wheels specified by the vehicle or wheel manufacturer, in newtons (N);

S - The strengthening factor, see Table 1.

6.1.3 Test procedures

6.1.3.1 Refer to Figure 1 for a way to clamp the test wheel to the test equipment.

Tighten the wheel tightening bolts (or nuts) to the torque value specified by the vehicle or wheel manufacturer. If it is not specified, it is recommended to tighten it according to Table 3. When using the device in Figure 1a) or Figure 1b) to test, check the amount of radial runout at the end of the lever arm. It shall not exceed 0.3mm when empty.

6.1.3.2 Set test parameters such as bending moment, speed and number of cycles. Start the test. In the initial stage of the test, the machine can be shut down to tighten the bolts or nuts once again. If the bolt breaks during the test, continue the test after replacing all the bolts.

6.1.3.3 Shut down after completing the specified number of test cycles. Use penetrant testing or other acceptable methods to check for wheel cracks.

6.1.4 Failure criterion In any of the following situations, the test is terminated and the wheel fails:

a) The test wheel cannot continue to bear the test load;

b) The original crack develops or stress causes new cracks to invade the wheel section;

c) The offset increment of the loading point exceeds 15% of the initial offset of the test.

6.2 Dynamic radial fatigue test

6.2.1 Test preparation The test equipment shall have a driven drum and wheel mount to make the wheel-tire assembly rotate under a fixed radial force, see Figure 2. The minimum diameter of the drum is 1700mm. The width shall be wider than the tire section. The surface shall be smooth. The connecting surface of the wheel mount shall have the same assembly dimensional characteristics as the connecting parts usually used on the vehicle. The surface hardness is recommended to be HRC40~HRC50.

The loading system shall maintain the specified load. The deviation does not exceed +/-2.5% of the calculated value of the test load. The loading direction is perpendicular to the surface of the drum. And it is consistent with the connection direction between the center of the wheel mount and the center of the drum.

The axis of the drum and the axis of the wheel mount shall be parallel. The wheels used as two wheels shall be tested in accordance with the wheels used for single wheels.