Fiber trapping in refining has been defined by the fraction f of the bar edges that trap fibers as they cross,and by the number of fibers i trapped under each section of bar.From these parameters,equations were derived to calculate the number of impacts that a fiber undergoes during refining and the maximum force experienced during each impact.Refiner power versus gap was measured for a conical laboratory refiner at maximum peripheral speeds ranging from 4 m/s to 27 m/s and consistencies ranging from 1% to 6% for one softwood kraft pulp.The data were used to calculate relative changes in i and f as a function of consistency and speed.It was found that f was extremely sensitive both to an increase in refiner rotational speed and to a reduction in pulp consistency.A reduction in consistency from 4% to 2% at 20 m/s(3000 rpm)led to a decrease in the trapping fraction,f,by approximately 80%.The number of fibers trapped under each section of bar also decreased,although to a lesser extent.The reduction in fiber trapping greatly increased the forces on the fibers,leading to enhanced fiber shortening and reduced refining efficiency.
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机译：精炼中的纤维截留是由在纤维交叉时截留纤维的条形边缘的分数f以及在每个条形截面下截留的纤维数目来定义的。根据这些参数，可以得出方程式，以计算撞击的次数。在圆锥形实验室磨浆机中，在最大圆周速度范围为4 m / s至27 m / s的情况下，精炼机功率与间隙的关系是在精磨过程中经历的最大力。一种软木牛皮纸浆，该数据用于计算i和f随浓度和速度变化的相对变化，发现f对精磨机转速的增加和纸浆浓度的降低非常敏感。在20 m / s（3000 rpm）下，稠度从4％降低到2％，导致捕集率f降低约80％。在每根条下捕获的纤维数量也减少了，尽管降低到a程度较小减少纤维截留大大增加了作用在纤维上的力，从而导致纤维缩短的缩短和磨浆效率的降低。
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