导流栅片弧形板式网槽

笔者从1985年开始,即着手对1092mm纸板机网槽进行研究与改进,对各类网槽进行了优劣对比,设计出扩缩导流栅片弧形板式网槽,一次性试用成功。 1991年1月,笔者又将扩缩导流栅片弧形板式网槽运用在1600mm纸板机上,纵横拉力比平均达到1.32:1,     

圆锥形多管扩缩活动弧形板式网槽的应用

<正>圆锥形多管扩缩活动弧形板式网槽应用在我厂二台1575mm双圆网双缸造纸机上,抄成纸张纵横抗张强度比由原来的3.0～3.7:1降到1.3～1.5:1一次性试用成功。生产的52g/m~2凸版印刷纸达到ZBY32026─90标准,深受用户欢迎,取得了较好的经济效益。 1圆锥形多管扩缩活动弧形板式网槽的结构图如下所示。     

侧向导流式网槽

侧向导流式网槽是在原用弧形板式网槽的基础上改进的。在弧型板面上镶了特制的导流板,使浆液在上网的过程中沿着导流板侧向流动,导流板分三段是 S 形排列。因此浆液在侧向流动过程中是要改变两次方向的,活动弧形板面导流板排列方式如图一,定向弧形导流板排列形式如图二。     

方锥形布浆式网槽的应用和成效

方锥形布浆式网槽的应用和成效吉林省榆树市造纸厂有两台多缸多网圆网纸机：１号１０９２纸机６网２６缸，主要生产铸涂原纸和白纸板，１９８８年以前生产扑克牌纸板；２号１６００纸机７网３２缸，主要生产扑克牌纸板。两台纸机均为活动弧形板式网槽。扑克牌纸板存在的主...     

侧流弧形板式网槽的设计和应用

本文介绍了侧流弧形板式网槽的设计原理、结构、调控和应用。实践表明:侧流弧形板式网槽不仅特别适用于要求纵横张力比小或横向强度大的特殊品种,也适用于一般品种。同时对原料和工艺的变化有较强的适应性。     

测定浓度,改变流程,克服纸病

湖北监利县造纸厂有787多网多缸纸板机一台.面浆为漂白木浆与漂白苇浆,底浆为废纸浆。均为活动弧形板式网槽。生产时在纸幅上常出现搓浆现象。根据这一现象,我们调整定向弧形板使之不漏浆,把唇布高度改为30毫米,定向弧形板与网面距离为13毫米,开车后并未得到解决。后经测定各部浆料浓度,并认真观察变化. 根据测定浓度和现场观察发现:各部浓度在15分     

圆网纸机上浆系统的改造

1旧式网槽的不足目前我国仍有相当一部分纸机的湿部配备圆网成形,其进浆方式为纵轴线单管进浆,敞口式带挡板翻浆的旧式网槽。这种网槽的主要缺点是:纸浆布浆不均匀,浆速比网速慢,易发生纤维絮聚,出现浆疙瘩;纤维悬浮分散不充分,特别是纸浆进入弧形板上网成形过程中,浆速慢网速快,受剥离角、离心力作用的影响,致使纸页成形不良,组织匀度差,横幅定量差大,纵横拉力比大,无法满足较高级纸张的质量要求。2新新型网槽的结构为了解决这些问题,研制了新型方锥总管进浆多管布浆多级扩缩器网槽。该网槽是由方锥总管、多级扩缩器、设备调节机构和活动弧…     

使用活动弧形板网槽时匀度纸病的形成与防止

活动弧形板网槽是目前使用最普遍的一种网槽结构,对纸和纸板的生产都有很强的适应性,但要生产出一张匀度好的纸张,与活动弧形板网槽的使用操作有着密切的关系,当弧形板网槽操作不当时,纸上会产生匀度纸病——横道子。出现这种纸病首先应找出产生的部位,分析产生原因,然后进行调整解决。 1、由于弧形板前后摇动产生的横道子 ①产生原因 由于活动弧形板前后摆动,溢流浆位不稳,浆位呈周期性的上升和下降。当弧形板上端往前时,     

用压力喷网成形器代替活动弧形板式圆网槽的应用效果

本文主要阐述了压力喷网成形器的结构和工作原理，相对于活动弧形板式网槽的优势及压力喷网成形器在我厂一号纸机应用半年来，在提高产量、降低电耗和改善产品质量方面所取得的成效。     

技术服务

一、圆网造纸机多管扩缩网槽改造 圆网造纸机多管扩缩网槽,成功地解决了圆网纸机的纵横拉力比大、匀度差、横幅定量波动大的问题,使圆网机抄造的纸质量达到一般长网机的技术水平。该网槽结构新颖、调节灵活、不结垢、不变形、投资少、     

基于伺服控制技术的纸张力控制方法

为解决高速卷接机组和滤棒成型机组在纸臂辊远离最佳工作位置时产生的断纸问题以及减少电路板设计和维护费用,在专用电路板对主轴速度和纸臂传感器反馈两路输入信号进行线性化处理的基础上,改用伺服控制器直接接收两路输入信号,利用内部软件先进行线性化处理,再用双曲线环节进行补偿,对输出到拉纸辊电机的驱动信号进行及时调节。应用结果表明,纸臂运行平稳,调整范围合适。调整时纸臂动作柔和,摆动幅度小(±5°),成型纸断纸次数由原来的5～6次/d减少到偶尔出现1次,较好地满足了生产需要。     

竹/棉混纺织物的染整加工实践

针对竹纤维的特点，优选染整工艺，前处理采用溢流煮漂；丝光碱浓190～200g／L，车速40m／min；染浅色选还原染料，中深色选活性染料；后整理中采用亲水性柔软剂，烘干时避免高温。通过调节织物进布张力等一系列措施解决起毛、折皱这两个难题。     

箱纸板形稳性影响因素的研究与控制

以牛皮箱纸板为例从三个方面探讨了对其形稳性的影响：①纸浆种类及其化学成份；②浆料打浆特性及施胶；③纸页成形及干燥过程。较为详细地论述了网槽型式、抄造定量、横幅不同部位、牵引力、干网的使用、大烘缸的使用与形稳性的关系。     

罗伊斯液体还原染料

罗伊斯液体还原染料系采用美国RoycevatTM技术生产,具有优良的染色性能和环保性能。通过与传统粉体还原染料进行对比,并将液体还原染料实际应用于纯棉和涤棉织物长车轧染生产中。结果表明,液体还原染料使用简单,力分高,染料提升力好,染色效果与传统粉体染料相当;染深色时染料用量明显减少,生产成本降低;染液COD含量较粉体染料下降50%,降低了染厂污水处理负荷。     

孔板布浆导流短弧形板式圆网槽及其性能测定

介绍了孔板布浆导流短孤形板网槽的结构，并对其成形纸页性能进行测定，结果表明，这种网槽有较好的布浆成形性能，纸页横幅定量偏差较小，纵横向强度比较接近。     

Radially sawn timber

This work decribes deformation and crack formation in sawn timber of pine and spruce after first drying and subsequent cycles of resoaking in water and drying. The influence of annual ring orientation and the occurrence of juvenile wood was determined. In addition, the influence of compression wood, annual ring orientation at the edges of the cross section, the position of the board surface in relation to the pith, and the condition of the board surface i.e. whether wet or dry during resoaking were studied. When timber is exposed to repeated cycles of wetting and drying, warp, viz spring, bow, twist and cup, increases and is greater after the first cycle. The influence of annual ring orientation on spring, bow and twist depends on the type of deformation and on the kind of wood. Generally, the results indicated that timber with vertical and semi (half) vertical annual rings show less deformation (mean values) than plain sawn timber and timber containing pith. Cup is mainly caused by transverse anisotropy and is strongly influenced by the radius of the annual ring. Therefore, timber with vertical annual rings do not show any cup. Spring, twist and, especially bow are strongly influenced by compression wood. Large amount of compression wood in sawn timber increases such deformation. The distance between sawn timber in the log and the pith with surrounding juvenile wood is of vital significance for cracking. During moisture cycling, the amount of boards that develop cracks increased irrespective of their prior location in the cross section of the stem. Timber sawn from near the pith or distinctly containing pith has a higher relative crack length compared to timber sawn away from and lacking pith. In timber exposed to repeated cycles of wetting and drying the crack length increases irrespective of its prior location in the stem.     

靴形压榨装置靴压板压区曲面结构的设计

介绍了靴形压榨装置用靴压板的结构设计方法,利用CAE技术设计了靴压板压区的曲面结构形状,得出了描述曲面曲线形状的数学模型和曲面实体模型,为靴形压榨装置的国产化研究奠定了理论基础。     

PASSIM卷接机组风室导轨的改进

PASSIM卷接机组原设计中风室导轨存在对下层烟丝吸附力弱、烟丝在高速运动过程中容易打滑等问题,造成烟支空头率高和烟支重量不稳定。为此对风室导轨布局方式、截面形状和基体材料进行了改进。前后列导轨改为对称的阶梯形;截面形状由圆弧形改为斜面;基体材料采用不锈钢,工作面进行陶瓷喷涂处理。改进后风室导轨提高了对烟丝的吸附力,解决了烟丝打滑问题,避免了紧头位置在高速运动中偏移和烟丝束形状变化,烟支质量标准偏差降低了3.5 mg,空头产生率降低了0.3%,有效提高了烟支质量控制精度。     

Use of dry milk protein concentrate in pizza cheese manufactured by culture or direct acidification

Milk protein concentrate (MPC) contains high concentrations of casein and calcium and low concentrations of lactose. Enrichment of cheese milk with MPC should, therefore, enhance yields and improve quality. The objectives of this study were: 1) to compare pizza cheese made by culture acidification using standardized whole milk (WM) plus skim milk (SM) versus WM plus MPC; and 2) compare cheese made using WM + MPC by culture acidification to that made by direct acidification. The experimental design is as follows: vat 1 = WM + SM + culture (commercial thermophilic lactic acid bacteria), vat 2 = WM + MPC + culture, and vat 3 = WM + MPC + direct acid (2% citric acid). Each cheese milk was standardized to a protein-to-fat ratio of approximately 1.4. The experiment was repeated three times. Yield and composition of cheeses were determined by standard methods, whereas the proteolysis was assessed by urea polyacrylamide gel electrophoresis (PAGE) and water-soluble N contents. Meltability of the cheeses was determined during 1 mo of storage, in addition to pizza making. The addition of MPC improved the yields from 10.34 +/- 0.57% in vat 1 cheese to 14.50 +/- 0.84% and 16.65 +/- 2.23%, respectively, in vats 2 and 3 and cheeses. The percentage of fat and protein recoveries showed insignificant differences between the treatments, but TS recoveries were in the order, vat 2 > vat 3 > vat 1. Most of the compositional parameters were significantly affected by the different treatments. Vat 2 cheese had the highest calcium and lowest lactose contencentrations. Vat 3 cheese had the best meltability. Vat 1 cheese initially had better meltability than vat 2 cheese; however, the difference became insignificant after 28 d of storage at 4 degrees C. Vat 3 cheese had the softest texture and produced large-sized blisters when baked on pizza. The lowest and highest levels of proteolysis were found in vats 2 and 3 cheeses, respectively. The study demonstrates the use of MPC in pizza cheese manufacture with improved yield both by culture acidification as well as direct acidification.     

直投式与传统发酵泡菜工艺中病原菌的变化规律

以植物乳杆菌NCU116作为直投式发酵剂,研究自然发酵泡菜与直投式发酵剂发酵泡菜过程中大肠菌群、沙门氏菌与金黄色葡萄球菌的变化规律。结果表明：直投式发酵剂发酵和自然发酵过程中,3种病原菌的数量变化趋势一致,均是在发酵前期上升,当达到最高值后下降,最终在泡菜环境中消失。然而,与自然发酵相比,直投式发酵剂发酵可显著降低泡菜发酵过程中3种病原菌的数量(P＜0.05),且在发酵的第2天即消失。自然发酵环境中沙门氏菌、金黄色葡萄球菌和大肠菌群分别在第3、3.5、4.5天消失。表明直投式发酵中植物乳杆菌NCU116对泡菜发酵过程中病原菌的生长具有显著的抑制作用。