Research on process parameters in a novel drafting system

To overcome the shortcomings existing in the roller drafting system of air jet spinning, a set of combing roller-drafting system has been introduced to substitute the roller drafting system in air jet spinning. Moreover, a funnel-shaped fibre conveyer, a disc fibre collector and a swirl twister have been designed to accomplish the spinning process, which was named disc swirl spinning. Experimental spinning proves that combing roller drafting device wears little. Its remarkable advantage lies in the high efficiency of drafting. The rotational speed of jet stream in nozzle can be well utilized, which promises a high productivity. The relationship between the drafting process parameters of disc swirl spinning and yarn properties, such as tenacity and peeling-off-resistance, has been investigated and the data suggest that yarn properties keep stable when combing roller speed is 6000–7000 rpm, feeding quantity is 1.695–2 g/min, sliver linear density is 2–2.58 g/m, feeding tension is 0.012 N and the unwinding tension of the core filaments is 0.06 N. Furthermore, the appearance of disc swirl spun yarn is compared with that of air jet spun yarn. The scanning electron microscope (SEM) photos show that yarn structure of disc swirl spun yarn is similar to that of air jet spun yarn. The core is bound by the outer fibres and it is nearly parallel and no twist. However, the outer fibres of disc swirl spun yarn cover yarn body totally, which is different with that of air jet spun yarn.     

A neural network meta-model of roll-drafting process

This paper presents a neural network based meta‐model of the roll‐drafting process which was elaborated on the basis of a discrete‐event simulation model presented previously. The GRNN, RBF, MLP3, and MLP4 networks were trained, tested and compared. The training set for the neural networks was obtained from the discrete event simulation model, which is characterized by a beta‐distributed velocity change point and satisfies the first and second limit schemes of the roll‐drafting process. A comparative analysis of the four different types of meta‐models led to the conclusion that the MLP4 meta‐model provides the best prediction of roll‐drafted fibrous material irregularity. Testing of the developed meta‐model has shown a high‐level coincidence between this meta‐model and the DES model of the roll‐drafting process.     

纺纱牵伸胶辊胶圈应用技术概要

阐述棉纺牵伸胶辊、胶圈的应用技术和牵伸原理,重点探讨了胶辊、胶圈的牵伸工艺特性及其合理配置、胶辊制作、周期管理、质量管理、使用管理、产品缺陷与其机械波分析、纺纱环境和挡车工操作水平对纺纱性能的影响,提出胶辊、胶圈有关机件的质量要求等。     

用电容式条干均匀度仪测定及控制纺纱质量

探讨了纺纱质量测控的中心环节－－使用以ＵＳＴＥＲＴＥＳＴＥＲ为代表的电容式干均匀度仪器测定条干均匀度时的结果分析及实际应用。其中涉及电容式条干均匀度仪的测试结果分析及应用、波谱图的分析及应用、设备的机械问题在波谱图上所造成的不匀波长的计算、纺纱条干均匀度指标及控制、纺纱质量控制方案及要求等几个方面的内容。     

工程地质专业技术发展50年回顾

文章以几个不同时期的水电站所做的工程地质工作为代表，回顾了西北院工程地质专业５０年的发展历程，文中叙述了工程地质从应用地质传统理论到应用地质力学、岩体力学、块体理论、工程动力地质理论、动态分析理论、环境工程地质理论的发展过程。工程地质条件的分析评价方法从宏观定性到即宏观定性又微观定量有机辩证相结合的进步过程。进入９０年代，由于设备的更新，计算机和ＣＡＤ软件的应用，使工程地质专业的技术发展迈向了一个     

细纱机四皮圈牵伸装置对成纱毛羽的影响

对采用四皮圈牵伸装置和采用普通细纱牵伸装置纺制纱线的毛羽进行了实验对比，分析表明四皮圈牵伸装置由于加强了对后区纱条运动的控制，可以显著减少成纱毛羽，尤其是3mm以上的长毛羽。     

曲线牵伸上销对紧密纺成纱条干影响的探讨

细纱机后区牵伸形式影响成纱条干.对现有的细纱机后区牵伸形式进行分析,介绍了曲线牵伸上销对后区牵伸形式的影响,并对普通紧密纱和曲线牵伸上销纱线进行了测试,结果表明曲线牵伸上销对14.6tex和9.8 tex的紧密纺成纱条干改善明显,但7.3tex的紧密纺成纱条干恶化.     

单摇架五罗拉双牵伸花式捻线机的开发

阐述了单摇架五罗拉双牵伸机构的机理和机器特点，叙述了与其他双牵伸形式的不同点，介绍了几种典型花式纱线。     

基于SolidWorks2010在《机械制图》教学实践中的应用

《机械制图》是工科院校的一门很重要的专业基础课,对学生空间想象能力的要求很高,难以通过书本、黑板和静态投影来实现教学。通过对三维制图软件solidworks2010的部分功能进行介绍,来阐释三维制图软件在制图学习中对实体的认知及各种视图绘制起到的辅助作用,以培养同学们的空间想象能力,提高学习效果。     

牵伸对纱条条干不匀影响的模拟研究

牵伸时纤维运动引起其排列变化是影响牵伸后纱条条干不匀的关键。为探究纤维变速点分布对牵伸后纱条条干不匀的影响,通过计算机模拟了实际纱条中的纤维排列(实际纱条),分别对理想纱条和实际纱条牵伸过程中的纤维运动进行了模拟,计算了在不同变速点分布下牵伸后纱条的条干不匀,并进行实验验证。结果表明:与理想纱条相比,实际纱条的条干不匀模拟值更接近实测值,且实际纱条能体现牵伸中变速点分布对牵伸后纱条条干不匀的影响,即变速点分布越分散,牵伸后纱条条干不匀越大;实际棉条模拟牵伸后的条干不匀值与实测值变化趋势一致,可用来预测牵伸后纱条的条干不匀。