酶在纺织行业的应用及发展前景

本文着重介绍了纤维素酶和蛋白酶在纺织行业的应用及酶在纺织行业的发展前景。     

CJ 5.8 tex紧密纱高密直贡缎的开发

为了顺利生产经纬纱均为紧密纱的细号高密直贡缎产品,重点介绍了紧密纺特细号纱,浆料配方、浆纱工艺及织造工艺的参数设置和织造效果.强调紧密纺特细号纱采用"两中一低"的浆纱工艺;织造过程中采用早开口,迟引纬,调整绞边及废边纱穿法,有效解决了织造疵点,使织造效率达到82%以上.     

莱赛尔棉集聚纺高密织物的生产实践

探讨莱赛尔LF棉集聚混纺高密织物的生产工艺。以莱赛尔LF/C 60/40 9.7tex集聚纱为经纱,采用ESPERO-M型络筒机,络筒速度1 000m/min,卷绕密度控制在0.5g/cm3以下,减少筒纱毛羽;采用ZC-L-180型分批整经机,总经根数18 094根,整经速度为650m/min;采用S632型浆纱机,优化浆料配方和浆纱工艺,新配方浆纱速度60m/min,并采用后上蜡工艺;使用OMNIPlus 800-340型喷气织机,织机速度550r/min,主喷气压0.4MPa,辅喷气压0.45MPa,上机张力3 000N。通过采取一些列技术措施,最终织机效率达90.92%,下机一等品率达98.5%。认为:通过优选无PVA浆料,可以降低生产成本,保证产品质量。     

QFN引线框架全自动贴膜装置的设计

设计了一种方形扁平无引脚封装(QFN)引线框架全自动贴膜装置,可以满足半导体QFN引线框架生产企业和半导体后道封装测试企业的生产工艺需求。介绍了这一贴膜装置的设计要求、结构、工艺流程、人机界面,分析了上料存料机构模组、贴膜机构模组、上下料搬运机械手模组,并给出了贴膜塑封效果。应用这一贴膜装置,能够解决QFN产品在塑封工艺阶段的溢料问题。     

粗纱机上部断面工艺的探讨

通过对粗纱机上部断面工艺参数与上部断面尺寸关系式的推导和实例测算，分析导纱角、纺纱段长度、前罗拉包围弧对粗纱伸长率和粗纱重量不匀率的影响，提出国内纺织机械厂应重视对粗纱机上部断面尺寸的设计，从工艺的合理配置和粗纱机结构设计上达到改善粗纱和细纱质量的目的     

精梳特细号纱生产工艺要点

为提高特细号纱的成纱质量水平,针对特细号纱成纱截面纤维根数少、强力低、纺纱过程中易断头、棉结易显现等问题,通过选择适当的工艺流程,采用双精梳工艺,并加强各系统工艺研究,合理配置各工序工艺参数,加强设备基础管理,提高设备运转状态等技术措施,使成纱质量各项指标达到要求,取得了较好的效果.     

超宽热压机框架有限元分析及结构优化

以某公司生产的4英尺×9英尺横向进板超宽热压机为分析对象,采用有限元方法对热压机框架板进行了应力状态与形变分析,提取出框架板在关键位置处的应力及位移数据;并以APDL建立了框架板参数化有限元模型,结合ANSYS优化设计模块,对框架板结构参数进行了优化计算,在以节约材料和保证其性能的前提下,确定了单块框架板的最优结构,并对优化参数后的框架板进行了有限元分析,验证了优化结果.     

铸旋铝合金轮毂旋压模具设计及压料方式研究

对铸旋铝合金轮毂旋压模具的设计进行了有限元热模拟分析,并经试验验证,旋压模具选用4.5‰的热膨胀系数是正确的.对于正面非机加轮毂,提出了轮毂旋压时采用中心凸台和工艺轮唇同时压料的方法,根据车轮不同结构,尾顶压力范围控制在4.5～6 MPa,并在生产中得到广泛应用.     

Dynamic analysis methodology for progressive failure of truss structures considering inelastic postbuckling cyclic member behavior

Over the years, several catastrophic collapses of truss structures have been reported. Sudden failure or reduction in member capacity of a single member in a truss structure gives rise to dynamic force redistribution in the remaining members and may lead to progressive collapse of the entire structure. During failure, truss members can undergo inelastic cyclic behavior (including postbuckling in compression and yielding in tension) that may not have existed in the intact structure. This paper presents a methodology to incorporate the inelastic cyclic member force-deformation behavior in the dynamic analysis of truss structures and at the same time incorporates the possible dynamic effects arising from the sudden change in load carrying capacity of a member due to failure or buckling/postbuckling. The method tracks and generates the force-deformation characteristics of every member of the truss at each incremental time step. The continuous change in the load-carrying capacity and the stiffness of members during the nonlinear force-deformation history has been incorporated in the analysis scheme using the Pseudo-force approach. The solution methodology for obtaining the dynamic response of the structure is based on the finite element technique and considers elasto-plastic material and large deformation geometric nonlinearities. The methodology is applied to a two-dimensional three-member toggle redundant truss subjected to external static, quasi-static, and dynamic (sinusoidal and ramp) loads. Results delineating the effects of the inelastic cyclic axial force-deformation relation of each member and the time variation of joint displacements and member forces are presented for each loading condition. The results show that there exist cases where modeling a compression member with its actual postbuckling behavior, which although has some reserve load carrying capacity, are more critical than the case where the same member is considered to suddenly lose its full load carrying capacity at its buckling load.     

惯性导航原理在确定井的姿态中的应用

本文根据飞机定向的方法,讨论了惯性导航系统在确定油井姿态中的应用,并且推导出了由三个加速度计和三个磁通门构成的测斜系统的数学模型以及测斜系统的实现方法。