This standard specifies the measurement tools and accuracy requirements, measurement conditions, measurement methods, data calculation and processing, and test reports for the outer edge dimensions of tires (tyres, inner tubes and pads). This standard applies to all new passenger car tires, truck tires, agricultural tires, off-the-road tires, industrial vehicle pneumatic tires and motorcycle tires.
GB/T 521-2003 history
2023GB/T 521-2023 Measurement method of tire outer edge size
2012GB/T 521-2012 Test method of measuring peripheral dimensions for tyres
2003GB/T 521-2003 Test method of measuring peripheral dimensions for tyres
1993GB/T 521-1993 Method of measuring tyre peripheral dimensions