匀浆辊流浆箱中匀浆辊的波迹效应

匀浆辊流浆箱以转动的孔辊作为匀整元件 ,匀整浆料的流速 ,具有整流和分散纤维的作用 .该文主要讨论波迹效应对匀浆辊设计的影响 ;匀浆辊流浆箱的匀浆辊 (闸辊 )的波迹效应产生的纤维定向条纹 ,导致整流效果不良 ,最终引起涂布、压光中的纸病 ,影响印刷质量 .经分析 ,这种波迹效应引起的纤维定向条纹 ,不同于简单的定量条纹 ,改变匀浆辊的运行参数、几何参数并不能消除 .匀浆辊的转动 ,必然产生哪怕纵向上轻微的涡流 ,就不可避免产生定向问题 .因此 ,匀浆辊流浆箱只适用于中低速纸机 .

Wake effect in rectifier roll headbox

In the rectifier roll headbox, to disperse and perforate fiber, the winding rectifier rolls are used to keep the flow velocity evenly. This paper mainly discusses the influence of wake effect during the headbox design. In the rectifier roll headbox, the wake effect of slice roll generates fiber orientation streak, which results in poorly perforating and leads to paper flaw during coating and calendaring. By analysis, the fiber orientation streak due to wake, is different from the simple basis weight streak and cannot be eliminated by changing the operating parameters and geometric parameters. The winding of rectifier roll, which generates slight vortex in machine direction, will inevitably leads to fiber orientation problems. So rectifier roll headbox can be only used in the middle or low speed paper machine.