Design and application of rolling axial system for controlling size range of tobacco strips

In order to control the size range of strips in the process of green leaf threshing, a rolling axial system was designed based on the principle of differential threshing. The system mainly includes a vibrating conveyor, a rolling axial screen, a large strip processing device and a pneumatic separator. The vibrating conveyor loosens tobacco to achieve high screening efficiency; the rolling axial screen and large strip processing device reduce the size of the large strips and sort out the stem-containing strips. Taking C3F tobacco leaves harvested in 2018 from Pingdingshan in Henan as test material, four technologies, including optimized basket, flat vibration screening re-threshing, rolling axial system and the conventional green leaf threshing, were parallelly tested. The results showed that the rolling axial system significantly raised the proportion of strips with the desired size range of 10 mm×10 mm to 35 mm×35 mm up to 69.20%, and the proportion of strips smaller than 10 mm×10 mm did not increased significantly; the stem content in lamina decreased to 0.99%; and uniformity coefficient increased to 1.04%. This method provides a technical support for promoting the uniformity of strips' size distribution.