Understanding friction

摘要

Friction plays a critical role in many web handling and winding problems in the paper industry. Although these problems can often be reduced to simple mechanical models, the models require the coefficient of friction of the material as an input. However, coefficient of friction of paper can be an elusive measurement which depends on measurement conditions, handling and even on previous measurements on the same sample. This paper looks at how friction should be measured for different applications. Fundamental principles are used to explain the chemical nature of friction which is essential for understanding and controlling friction in the paper industry.