【作者】 赵睿哲；

【导师】 郁崇文；

【作者基本信息】 东华大学 ， 纺织工程， 2004， 硕士

【摘要】 苎麻中超长、倍长纤维的大量存在对苎麻纺纱的危害很大。将牵切技术应用在苎麻纺纱中，可以有效地减少超长、倍长纤维，在苎麻行业实际生产中具有现实意义。本文对苎麻牵切设备的研制，及相关牵切工艺的确定作了初步研究。主要内容包括： 1、参照化纤、羊毛的牵切工艺自主研制开发苎麻牵切机。 2、根据苎麻纤维的特点及试验结果对苎麻牵切机技术指标及工艺参数进行优化与调整。 3、用回归分析、数理统计等数学方法建立数学模型，并确立牵切机工艺参数与牵切条质量的回归关系。 通过理论分析与试验验证相结合的方法，对苎麻牵切机各项技术参数进行了确定；建立了牵切运动中的纤维断裂模型；运用优化设计对苎麻牵切工艺参数进行了优化；对精干麻牵切工艺与精干麻切断工艺进行了比较；对精干麻牵切工艺与传统的精干麻梳理工艺进行了比较。结果表明： 1、牵切工艺对苎麻纤维物理性能的损伤是很小的。 2、牵切机采用前区牵伸，后区牵切的配置。总牵切倍数确定在7倍以上，10倍以下。前区牵伸倍数确定在1.5倍，后区牵伸倍数确定在4.5～6.5倍。 3、确定精干麻的喂入定量定为200g／m，麻饼的喂入定量定为300g／m，BR221条喂入定量定为100.9g／m，CZ191条喂入定量定为134.4g／m。 4、加压为0.35Mpa～0.45Mpa时，80度皮辊与90度皮辊的握持弧长差异不大，基本稳定在13—14mm，取其平均值为13.5mm。 5、建立了牵切运功中的纤维断裂模型，原料牵切后的平均长度理论值在一定误差范围内与实际值基本吻合，该模型及假设成立，并对牵切机隔距与各指标的关系进行了分析与拟合。 6、对精干麻与BR221条牵切工艺参数进行了优化。精干麻牵切时，牵切机的最佳工艺参数配置为：牵切隔距为122.2mm，牵切加压为0.48Mpa，后区牵切倍数为5.1倍。根据该工艺配置进行试验，得到精干麻牵切后各项指标为：平均长度为62.8mm；长度不匀为67.3％；短纤率为34.3％；长摘要纤率为2.9%;麻粒为12(个/g);硬条为1.9%。7、BR221条牵切时，牵切机的最佳工艺参数配置为:牵切隔距为128们n们。，牵切加压为0.4MPa，后区牵切倍数为4.8倍。根据该工艺进行试验，得到BR221条牵切后各项指标为:平均长度为55.3rn们以;长度不匀为75.2%;短纤率为39.4%;长纤率为8.7%;麻粒为59(个/g);硬条为0.31%。8、精干麻牵切BR221条牵切进行比较得出，选用精干麻牵切不但可以节约成本，牵切效果也理想和显著。9、精干麻切断试验与精干麻牵切试验的试验结果相比较，牵切工艺优于切断工艺。10、精干麻牵切有其显著的优越性，牵切后各项指标均符合甚至优于精干麻梳理后的梳麻麻条。更多还原

【Abstract】 Over-length in ramie fibre does have great harm to ramie spinning. The appliance of stretch-breaking can dramatically cut down the number of over-long fibre and achieve the economic purpose in ramie textile industry.This thesis focuses on the researches in the following aspects. Firstly, according to the man-made fibre and wool stretch-breaking machine, develop ramie stretch-breaking machine.Secondly, optimize and adjust the technical parameters of the machine according to the characteristics of ramie and the experimental results.Finally, establish mathematic model and analyze the relationship between the technical parameters of the ramie stretch-breaking machine and the quality of the ramie stretch-breaking strip.The experimental results are as follows. Firstly,’ ramie stretch-breaking machine adopt that the front field is the drafting field and the back field is the stretch-breaking field, total drafting multiples are above 7 and below 10. The front drafting multiples are 1.5 and the back drafting multiples are 4.5-6.5. The feed quantum of BR221 strip is 100.9g/m, and CZ191 strip is 134.4g/m. The schopper hardness of the top roller is 90. The average length of the gripping arc is 13.5mm.Secondly, as to three different materials, the errors between theoretic average length got by the stretch-breaking model and actural numbers got by the experiments are fluctuating. With an error range, the model and hypothesis are correct.Thirdly, optimize degummed ramie and BR221 strip stretch-breaking process. As to degummed ramie, technical parameters are as follows.Stretch-breaking guge is 122.2mm. Stretch-breaking pressure is 0.48Mpa. Back field stretch-breaking multiple is 5.1. The experimental results are as follows. Mean length is 62.8mm. Irregularity of length is 67.3%. Staple rate is 34.3%. Over-length fibre rate is 2.9%.Nep number is 12. String rate is 1.9%. As to BR221 strip, technical parameters are as follows. Stretch-breaking guge is 128mm. Stretch-breaking pressure is 0.4Mpa. Back field stretch-breaking multiple is 4.8. The experimental results are as follows. Mean length is 55.3mm. Irregularity of length is 75.2%. Staple rate is 39.4%. Over-length fibre rate is 8.7%.Nep number is 59. String rate is 0.31%.Finally, compared degummed ramie with BR221 strip stretch-breaking, degummed ramie stretch-breaking is more economical and the experimental effect is more notable. The ramie stretch-breaking machine can carding degummed ramie continuously and dose less harm to the fibre. After stretch-breaking, the fibre has a better straightness and parallelization and over-length fibre, nep and string are reduced dramatically.更多还原