BS ISO 11093-7:2011

This standard BS ISO 11093-7:2011 Paper and board. Testing of cores is classified in these ICS categories:

• 85.080.30 Cardboard
• 85.060 Paper and board

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:

—	internal diameter:	50 mm to 350 mm;
—	minimum wall thickness:	0,05 × internal diameter, but not less than 10,0 mm;
—	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.