The ISO 11093-7:2011 standard specifies a method for determining the flexural modulus of paper and Cardboard cores using the three-point method. This method is suitable for cylindrical paper and Cardboard cores with an inner diameter of 50mm to 350mm, a minimum wall thickness of not less than 10mm and a minimum length of not less than 10x the inner diameter. The three-point bending test allows for precise measurement of the resilience modulus of the core to evaluate its bending performance during processing and use. This standard provides a uniform test method for the paper industry, which helps to optimize the production process and quality control of paper cores.