过程能力分析在制丝工艺技术改进中的应用

为稳定、提高卷烟制丝质量,采用统计过程控制技术对制丝关键工序重要参数进行了评价,发现润叶加料、混丝掺配加香工序有待改进,对其进行改进后,再次利用统计过程控制技术进一步完善制丝质量考核体系。结果表明:①经改进后的制丝生产工艺关键指标过程能力指数PPK(Preliminary Process Capability Index)值平均提高了0.23,润叶加料均匀性标准偏差降低了56.5%,梗丝掺配均匀性由改进前的94.27%提高到97.38%;②改进前后批内、批间卷烟样品的感官质量得分波动值分别降低0.29和0.27分,说明改进后批内、批间的内在质量更趋于稳定;③完善制丝质量考核体系后,松散回潮热风温度、润叶加料入口流量、加料比例、烘丝热风温度、加香瞬时比例5个指标的平均PPK值提高6.1%。

Application of Process Capability Analysis in Upgrading of Primary Processing

For stabilizing and improving the quality of primary processing,SPC(statistical process control)was used to evaluate key parameters in primary processing,the process steps of ordering,casing,cut rag blending and flavoring were evaluated and improved.After then,the quality audit system was further improved by SPC.The results of improvement showed that: 1)the process capability index,PPK,of key parameters in primary processing increased by 0.23,the standard deviation of tobacco casing decreased by 56.5%,and the uniformity of cut stem blending increased from 94.27% to 97.38%;2)the intra-and inter-batch fluctuations of sensory quality scores of cigarette samples reduced by 0.29 and 0.27,respectively,it indicated that the intrinsic quality became stabler;3)the average PPK value of 5 indexes(hot air temperature in ordering cylinder,throughput of casing cylinder,casing ratio,hot air temperature in tobacco dryer,instantaneous flavoring ratio)increased by 6.1%.