Takashi Kadoya

A Tester for Continuous Determination of the Freeness (2)

In the Previons paper, it was shown that there was close correlation between the Canadian Standard Freeness and drainage, and that it was possible to know the Freeness by measuring the latter. Here according to this principle, the authors made a new Freenes-tester which has an apparatus drising a cylinder with wire cloth and an automatic recorder measuring the time required for water to reach to a given level. Under different kinds of conitions, the new tester was used. The tester was tested instock of L-BKP (cons. 0.5%) and N, L-mixed BKP (cons. 2.7%) in the range of freeness 200cc450cc and it was recognized that there was linear relationship between reading of the tester and freeness in the log-log scale, besides there were only small fluctuations in each measuring point. In general, the bottom wire cloth type was used in the low consistency of stock and the side wire cloth type was used in the high consistency. The tester, which was the side wire cloth type, was really used in measuring the freeness of L-BKP stock (csf=350cc, 420cc, consistency 4.8%) in a paper-mill and there were only about ±10cc differences between the freeness obtained by the tester and really measured values. Finally the influences of temperature, consistency, clay-contents and flow rate of stock to the reading of the tester were discussed.