打叶器结构对打后片烟片形的影响

Effects of thresher parameters on shape of threshed strips

为解决当前打叶复烤生产中打后片烟大片率偏高、片形结构不合理等问题,以打叶机组第一级打叶器为对象,根据打辊打刀与框栏间的刀框距、打刀排列方式和形状、框栏形状等因素设计了5种打叶器结构,并考察了不同打叶器结构对打叶效率、片烟结构、片烟片形的影响。结果表明:(1)不同打叶器结构的一级打叶效率、打后片烟结构和片烟片形均存在差异。(2)调整后打叶器以加密菱形框栏、矩形打刀和梯形打刀混用、打刀品字形排列为最优结构组成。(3)调整后大片率降低6.55百分点,中片率提高6.35百分点,大中片率和碎片率保持不变;大片长宽比在1.2~1.5的片烟数量增加最多,为9.07%;大片和中片的长宽比在2~3的降低最多,分别为9.59%和7.57%。通过调整一级打叶器结构,有效提高了打叶效率,改善了成品片烟质量。

In order to lower the percentage of oversize strips after threshing,five combinations of parameters were tested for the first stage thresher,including clearance between teeth and frame basket,the arrangement of teeth and the shape of frame openings. The results showed that：1） The threshing efficiency and the size and shape distribution of threshed strips differed between different combinations of parameters. 2） The preferable combination of parameters included denser rhombic frame basket openings and mixed rectangular and trapezoidal teeth arranged in Y-shape. 3） Under the preferable conditions,the percentage of large-sized strips decreased by 6.55 percentage points, that of medium-sized strips increased by 6.35 percentage points, while the percentages of large-and medium-sized strips and small-sized strips kept unchanged. The amount of large-sized strips with the length to width ratio of 1.2-1.5 increased obviously （by 9.07%）, and the amount of large-and medium-sized strips with the length to width ratio of 2-3 decreased obviously （by 9.59% and 7.57%,respectively）. The parameter-modified first stage thresher effectively promotes threshing efficiency and generates better strips.