橡毯预缩机预缩率软测量模型

针对染整后整理预缩工序,由于橡毯预缩机预缩效果的影响因素多而复杂,难以实现预缩率的在线预测和预缩工艺的精确定量设计问题,采用机理建模的方法,分析橡毯预缩机橡胶毯的变形机理,建立了预缩率与对其影响最大的因素挤压力之间的软测量模型。实例结果表明：根据所建立软测量模型计算出的预缩率与实测值的相对误差均在8%以内,平均绝对百分比误差为5.1041%,该软测量模型是可行有效的,对预缩率在线预测和预缩工艺的精确定量设计具有指导意义。     

国外简讯

机械预缩机的新一代弹性橡胶毯 据法国Rollin SA公司报道,其提供用于机械预缩机的TOP Shrink弹性橡胶毯具有使用寿命长,性能稳定,耐弯耐压,外观不易变形等优点。 织物机械预缩的均匀性和规一性,很大程度上取决于织物本身的性质和采用的预缩方法、预缩机和弹性橡胶毯。 织物在湿热状态下,通过弹性橡胶毯粘附性能的连接作用,使经纬密度增加,实现机械预缩。然后当织物离开预缩机时,即刻烘干,使缩率永久固定。机械预缩还能改善织物的外观,如光泽和手感。 预缩过程可以分成二个主要步骤进行,预缩阶段,通过橡胶毯挤压,使织物预缩;热固阶段,通过橡胶毯和加热转鼓作用使织物缩率固定。 预缩的产生是由于弹性橡胶毯的挤压作用,降低了织物的运行速度,另一方面,使织物的纱线均匀滑移。     

牛仔布的预缩整理与回伸的研讨

通过对织物缩水机理的讨论,介绍防止织物缩水的预缩方法和橡胶毯预缩机预缩的原理。并针对橡胶毯预缩后存在的长度回伸和使用过程中裤缝扭转问题,提出解决办法。给针对制定工艺和织物标准提供参考和帮助。     

印染厂节能减排实用工艺装备技术(二十一)——织物缩水率的控制

(3)承压辊直径越小,预缩率越大 承压辊直径减小,橡胶毯的变形量随之增加,从而可达到较高的预缩率.但承压辊直径过小,织物在预缩区湿热定形的时间过少,影响预缩的稳定性;且橡胶毯会因挠曲次数增加产生疲劳而缩短使用寿命. 从目前使用情况来看,采用50mm橡胶毯,承压辊直径为Φ500mm;采用67mm橡胶毯,承压辊直径为Φ616mm. (4)布面及橡胶毯表面含湿量 ①预缩前织物的含潮率一般为10％-15％,织物的单位面积质量越大,含潮率也越大.纤维之间的水分是一种润滑剂,使纤维之间产生滑动而达到预缩效果. 织物经喷雾给湿后,再经过Φ570mm烘筒的烘蒸,是促使织物含潮均匀的一种常用方式.喷雾给湿时,可使用各种添加剂,但要注意,添加剂是一种润滑剂,既可以使织物收缩,也会造成织物伸长. ②橡胶毯表面的含湿量会直接对织物含湿量产生影响,一般可改变织物含湿率1％-3％.具体控制橡胶毯带水量主要有两个办法:一是选择不同号的砂带研磨橡胶毯,如60#带水量大,100#带水量小;二是改变压水辊压力大小,也可改变橡胶毯带水量.     

织物预缩整理的操作要点

为保证织物成品的尺寸稳定性,需进行预缩整理。预缩处理时必须保持预缩机车速稳定,进入橡胶毯单元的织物回潮率应维持稳定,橡胶毯单元中承压烘筒的蒸汽压力亦应充足稳定。文中给出了预缩处理时的操作要点,以及常见的疵病和解决措施。     

高效节能的预缩整理

<正>纺织品整理商迫于不断提高的成本压力,纷纷采用更高效且成本效益更高的整理工艺。就纺织品的受控机械预缩而言,现在的要求包括:更高的生产效率,更高的利用率,更高的缩率,更低的耗水量以及更长的橡胶毯使用寿命。Monforts新开发的橡胶毯预缩设备可满足以上需求。     

针织物汽蒸式预缩机的设计原理

服装材料在加工制作过程中，经过织造、精炼、染色、整理等各种理化处理，由于在各道工序中所受的强烈的机械张力，导致织物内部存在着不同的应力和其它病疵，这种情况若在制作服装前不加以消除，将会不同程度地影响服装产品的形态稳定性、穿着性能等。预缩整理正是消除和纠正这种影响的一种必要的工序，预缩机是具有对织物预缩整理功能的机械。预缩机的种类很多，通常有机械式的预缩机（如橡胶毯式、呢毯式、挤缩式等）；汽蒸式预缩机；超声波水汽雾化预缩机以及冷冻蒸发预缩机等。前一种预缩机（机械式）使用比较多，后两种预缩机由于结构…     

技术开发

POWER-SHRINK机械预缩整理机组在开始时,机械预缩整理机组用于机织物,特别是牛仔布整理领域。后来,机械预缩整理生产线结合呢毯轧光机或挤压式预缩机用于针织面料的整理。新的BRCKNER POWER-SHRINK机械预缩整理生产线提供了很多的可能性,即使是高度敏感的针织物的防缩,也可以实现光滑的触摸手感,非常低的织物残余收缩率,以满足高质量的产品要求。     

影响织物预缩率的重要因素分析

介绍了橡毯预缩机的预缩原理,着重分析影响织物预缩率的因素。     

推荐应用美国Daytex预缩胶毯

我公司地处广东省西礁 ,属民营企业。主导产品为 4 0 0g m2 ～ 5 0 0g m2 牛仔布或弹力牛仔布 ,配置有高速箭杆织机 ,预缩、染整生产线 ,产品销往国内市场 ,部分产品出口。为适应市场需要 ,于 2 0 0 2年 7月我公司新增一条烘燥后整理线。其中随郑州纺机厂预缩机配套引进一条美国Daytex预缩毯 ,上机使用至今 ,我们深感该毯质量良好。由于使用美国Daytex预缩毯 ,减少了打磨和换毯停台时间 ,工效大大提高 ,产品质量亦达到用户要求 ,为我公司创造了良好的经济效益。现将该毯推荐给同行。美国DayInternationalInc ,有 4 0年生产橡胶毯的历史 ,…     

食品装备管路自动涂胶装置及其挤出流道结构优化

目的:获得食品加工输送管路缠绕加热带表面粘接剂均匀、可控涂抹的胶层。方法:通过流变学试验获取硅橡胶本构模型,利用Polyflow仿真硅橡胶挤出流动过程,以加热带长度、宽度方向涂胶均匀性为目标,开发挤出试验机电系统,分析不同流道出口收缩段长度、出口厚度下的流速和体积流量分布特征,优化流道出口结构参数,经涂胶试验验证胶层均匀性,并迭代流道出口结构。结果:硅橡胶具有剪切变稀的特性;当收缩段长为5 mm,口厚为0.8 mm并在出口中心处距离边缘3.5 mm的位置线性扩展至1.05 mm时,涂胶均匀性最佳。结论:对硅橡胶流道出口两端边缘厚度加以线性扩展,能够改善涂胶均匀性;出口与加热带的间距及硅橡胶流速与缠绕速度匹配性是影响涂胶均匀性的另一关键因素。     

The Effect of Wheat and Maize Flours Properties on the Expansion Mechanism During Extrusion Cooking

The expansion mechanism in the extrusion cooking process was investigated during maize and wheat flours processing in a twin-screw extruder. An experimental study of extrusion process was carried out at constant moisture and specific mechanical energy. The expansion phenomenon which consists in a growth phase followed by a shrinkage phase was observed through an image processing method and analyzed by use of classical expansion indices: sectional, longitudinal and volumetric expansion indices. It was found that the maximum expansion is obtained with maize flour and that the difference in composition between maize and wheat flours has an impact on the expansion mechanism. Image analysis method enabled to obtain an instantaneous measurement of the growth and shrinkage parameters and appeared as useful tool to characterise expansion in function of extrusion conditions. A model based on the bubble growth in a viscous medium was proposed to analyze this expansion phenomenon. It enabled to study the evolution of expansion rates in function of the characteristic times of the problem: the bubble formation characteristic time and the maximum expansion time in both radial and longitudinal directions.     

碾搓式橡胶果脱壳试验

为研究橡胶果脱壳效率随相关参数的变化规律,确定最佳脱壳条件,根据碾搓原理研制了橡胶果脱壳试验机。通过单因素试验和正交试验,分析不同的挤压压力、摩擦速度和摩擦材料对脱壳率指标的影响规律及机器的最佳工作参数。结果表明:随着摩擦速度增大,脱壳率先增大后降低;随着挤压压力的增加,脱壳率线性增加;摩擦材料依次取钢板、塑料板、木板、橡胶板时,脱壳率逐渐降低。对橡胶果脱壳率的影响因素从大到小依次为挤压压力、摩擦材料、摩擦速度。当挤压压力为700N、摩擦速度为46 mm/s、摩擦材料为钢板时,橡胶果的脱壳率达到81.8%。研究结果可为橡胶果脱壳机的整体设计提供试验依据。     

Distortion of Norway spruce timber Part 1. Variation of relevant wood properties Part 1. Variation of relevant wood properties

) trees from one fast-grown and one slow-grown stand in southern Sweden. From the trees 240 studs (45 × 70 × 2500 mm) were taken for measurement of distortion. Wood properties were measured on small specimens (13 × 13 × 200 mm) cut from the studs. Spiral grain angle was found to vary from approximately +3° (left-handed) close to pith to zero 150 mm from pith with a strong individual variation. The material from the fast-grown stand had a larger spiral grain angle compared with the slow-grown material. Spiral grain was poorly correlated to other parameters. Presence of knots had a substantial influence on longitudinal shrinkage (α_l) measurements. Specimens with large knots (KAR > 33%) had almost 100% higher longitudinal shrinkage than specimens without knots. It should be pointed out, however, that measuring shrinkage in small specimens containing even small knots can create a problem with regards to the obtained results, especially results of α_l. It was found that presence of compression wood in several growth rings more than doubled the longitudinal shrinkage. For the radial and tangential direction the presence of compression wood decreased shrinkage with about 30%. The ratio between tangential and longitudinal shrinkage was 49 for normal wood whereas for compression wood the ratio was 13. These results confirm the theory that the microfibril angle governs shrinkage. Longitudinal shrinkage decreased slightly with increased distance from pith whereas radial and tangential shrinkage did not display any substantial radial variation. The fast-grown material had generally a higher longitudinal shrinkage and lower transverse shrinkage than the material from the slow-grown stand. About 50% of the variation in longitudinal shrinkage was explained by radial position, density and ring width. Density and ring width did explain 60% of the variation in radial shrinkage but only 30% of the variation in tangential shrinkage.     

低黏度油墨和橡皮布对无水胶印印刷导电层的影响研究

近年来,随着全球市场对电子器件需求量的不断增长,许多科研院所及部分企业都在尝试利用传统印刷(柔印、凹印、网印等)和数码印刷(喷墨印刷等)技术来制作电子器件。为了实现电子器件的高沉积精度,对印刷技术提出了以下几点要求:线条无缺陷,有锐边且分辨率高;图层无针孔,均匀且表面光滑;墨层厚度较薄。     

橡胶果破壳力学特性试验与分析

为研究橡胶果在不同条件下静态压缩破壳力的变化规律,对橡胶果分别进行X、Y、Z 3个加载方向的剪切力、锥刺力、挤压力的静态压缩试验;运用有限元法建立橡胶果的力学模型,研究橡胶果在压缩载荷作用下应力应变情况及损伤规律。试验结果表明:橡胶果在剪切力、锥刺力、挤压力下的破壳力大小关系为F_(挤压力)F_(剪切力)F_(锥刺力);橡胶果较佳的加载方向为Y方向;试验中Ⅰ类、Ⅱ类、Ⅲ类橡胶果的挤压破壳力分别为0.548 0,0.564 5,0.715 1 kN,破壳力随着橡胶果尺寸的增加而增加;有限元分析出最佳加载方向为Y方向,与试验结果一致。     

基于ADAMS的印刷滚筒刚柔耦合仿真分析

为研究印刷滚筒及橡皮布的变形对印刷品质量的影响,以印刷装置为研究对象,应用SolidWorks建立印刷滚筒的刚体系统模型,应用ANSYS建立橡皮布柔性体模型,在ADAMS中采用替换法建立刚柔耦合样机模型并进行仿真分析,得出了印刷过程中滚筒间轴向接触应力、橡皮布的应力及变形情况。     

组合式橡胶籽脱壳机构设计与试验

目的：解决现有的橡胶籽脱壳装置脱壳率、整仁率低,不足以满足不同条件下橡胶籽脱壳需求的问题。方法：设计了一种组合式橡胶籽脱壳机构,通过橡胶籽在凹槽板与旋转刀片的剪切以及对转叶片辊筒挤压、碰撞的组合作用下实现脱壳。运用EDEM离散元软件建立橡胶籽与脱壳机构的离散元模型,并对其脱壳过程进行模拟。采用响应面法分析剪切挤压间隙、叶片辊筒转速、叶片辊筒安装相位对橡胶籽脱壳率、整仁率的影响规律,优化获得最佳工作参数从而进行台架验证试验。结果：所设计的组合式橡胶籽脱壳机,最佳工作参数组合为剪切挤压间隙12.6 mm、叶片辊筒转速300 r/min、叶片辊筒安装相位40.5°。此时,橡胶籽脱壳率为94.09%,整仁率为96.47%。根据最佳参数组合进行台架验证试验,橡胶籽脱壳率为89.67%、整仁率为91.33%。结论：在橡胶籽脱壳装置设计过程中,离散元法可有效分析不同结构参数对性能指标的影响。     

Purpose-grown Wools

An account is given of an investigation of the dimensional changes in eyelet structures made from cotton, Vincel. and Courtelle yarns at three states of relaxation, namely, dry relaxation, wet relaxation, and washing. Observations revealed that the Courtelle structure exhibited a collapse in the configuration of the eyelet stitch when the fabrics were removed from the machine. It is suggested that this collapse could have been due to elastic recovery of the transferred yarn after stitch formation and to the presence of insufficient cohesion forces between the yarns within the structure.

Measurements of eyelet courses/in, (e _c), eyelet wales/in, (e _w), and eyelet density (E) showed that, in both the dry- and the wet-relaxed states, the fabrics exhibited a certain amount of distortion. It was concluded that the incomplete relaxation of the fabrics in these states was largely due to obstructional effects of the transferred loops. The agitation action of the washing treatment brought about a considerable rearrangement in the structure. This was particularly noticeable for the Vincel fabrics, whose geometrical parameters were readily represented by equations similar in form to those of the plain structure. The dimensional changes in length, width, and area due to washing showed an increase in the lengthwise shrinkage with the increase in loop length. Fabric-width shrinkage exhibited considerable change and reached maximum values of 42% and 26% for the cotton and Vincel fabrics, respectively, at greater loop lengths. Changes in area showed a decrease in the percentage shrinkage with the increase in loop length.