1 Scope
This part of ISO 11093 specifies a method for the determination, by the three-point method, of the flexural modulus of cylindrical paper and board cores which meet the following criteria:
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internal diameter: |
50 mm to 350 mm; |
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minimum wall thickness: |
0,05 × internal diameter, but not less than 10,0 mm; |
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minimum length of core: |
10 × internal diameter, but not less than 1 000 mm. |
If the flexural modulus has to be used for the calculation of a paper core’s natural frequency, ISO 11093-8[2] applies instead of this International Standard.