International Organization for Standardization

Paper and board — Determination of bending stiffness — General principles for two-point, three-point and four-point methods - Second Edition
 N 5628

Annotation

This International Standard specifies three test methods for determining the bending stiffness of paper and paperboard. The test methods differ in the type of loading mode, thus giving rise to the two-point, three-point and four-point bending test methods.

For paper and paperboard in a low thickness range, the two-point bending method and the three-point bending method are suitable.

For corrugated fibreboard and board with a higher thickness, the four-point bending method is recommended.

The measurement conditions are defined in such a way that the test piece is not subjected to any significant permanent deformation during the test, nor is the range of validity of the equations for calculating the bending stiffness exceeded.

In these bending tests, the test pieces of paper and board are regarded as "beams" as defined by the science of the strength of materials, see Reference [1].

Автоматический перевод:

Бумага и правление — Намерение согнуть жесткость — Общие принципы для двух пунктов, методы на четыре пункта и на три пункта - Второй Выпуск

Этот Международный стандарт определяет три метода испытаний для определения сгибающейся жесткости бумаги и строительного картона. Методы испытаний отличаются по типу погрузки способа, таким образом давая начало двум пунктам, методов испытания на изгиб на четыре пункта и на три пункта.