Morphological composition of web-break inducing shives in commercial newsprint pulp

Abstract

Web-breaks during paper production cause a serious inconvenience in production process and increase cost of production. Earlier studies indicate that web breaks occur at tensions far below the ultimate tensile strength values determined by tensile testing in the laboratory. It was also reported that most of the web-breaks were caused by shives (bundle of unseparated fibers). In this paper the result of an investigation 0n the morphological composition of shives in commercial newsprint pulp as a whole and those causing web- breaks is presented. It was found that 93% of the shives were earlywood and only 7% latewood.It was also determined that latewood shives are the main causes of web-break More than 90% of the" web-break inducing shives were found to be latewood shives.