GB/T 18506-2013Uniformity test method for motor vehicle tyres (English PDF)

1 Scope

This Standard specifies the test method for measuring the uniformity of passenger car tyres and truck tyres on the tyre uniformity test machine (drum method).

This Standard applies to passenger car tyres and truck tyres (including mini truck tyres, light truck tyres).

2 Normative references

The following documents are indispensable for the application of this document.

For dated references, only the dated version applies to this document. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 2977, Size designation, dimensions, inflation pressure and load capacity for truck tyres

GB/T 2978, Size designation, dimensions, inflation pressure and load capacity for passenger car tyres

GB/T 6326, Tyre terms and definitions

GB 9743, Passenger car tyres

GB 9744, Truck tyres

3 Terms and definitions

Terms and definitions determined by GB/T 6326 and the following ones are applicable to this document.

4 Test equipment and its requirements

5 Test conditions

5.6.2 If the test tyre is partially deformed due to storage, packaging and transportation, appropriate preheating repair can be used to reduce the deformation to an acceptable level.

5.6.3 In order to ensure that the tyre is properly seated on the rim, the surface of the tyre bead or rim bead seat or both may be coated with a suitable lubricant.

6 Test steps

6.1 Select and adjust the rim of the test machine according to the provisions of 4.3.

6.2 Install the tyre on the rim; inflate to the test pressure that is specified in 5.3.

6.3 Rotate the principal axis of the test machine at the speed that is specified in 5.5; move the test drum against the tyre until it reaches the specified load; keep the distance between the principal axis and the drum axis constant; make the principal axis rotate clockwise and counterclockwise for more than two cycles, respectively; record the following data after measurement:

a) Radial force variation RFVCW;

b) Lateral force variation LFVCW;

c) Lateral force deviation LFDCW;

d) Radial force variation RFVCCW;

e) Lateral force variation LFVCCW;

e) Lateral force deviation LFDCCW;

g) Radial force of first harmonic RFV1H;

h) Lateral force of first harmonic LFV1H;

i) Conicity CON;

j) Ply steer PLY.

6.4 Move the test drum away from the tyre; deflate the tyre; remove the tyre from the rim.

6.5 Mark the test tyres if necessary. […]