一种铝电解槽无筒无刷定容下料器的设计

设计了一种铝电解槽中使用的无筒无刷定容下料器,介绍了其工作原理及结构特点。并分别对无筒无刷定容下料器的关键零件从材料选择、强度校核、到结构配合等进行了阐述,并得出了不同要求下料量下料器的定容腔容积的计算公式。以此设计的下料器在生产应用中效果良好。     

大型预焙铝电解槽氧化铝浓度精确控制分析

本文阐述了大型预焙铝电解槽氧化铝浓度的控制,分析了影响氧化铝浓度精确控制的各种因素,针对影响氧化铝浓度精确控制的诸因素,提出了科学有效的解决方案。     

攀钢烧结松料器的改进

本文简要地介绍了攀钢烘铁厂烧结松料器的改进方法及改进后的使用效果,对松料器的改进作了具体的描述,并从机理上进行了分析。     

承钢150 m2烧结机布料系统的改进

为了提高烧结料层的粒度偏析和透气性，降低边缘效应，改善布料质量，对承钢150m^2烧结机布料系统进行了改进，包括：布料矿槽容积和形状的改进；五辊改九辊；重新布置松料器；增加压料器和九辊拦板等。改进后，取得了满意的效果。     

二升三维运动高效混料器

介绍了二升三维运动高效混料器的结构与运动特点。这种混料器在进行自转的同时还进行公转,物料在湍动下进行混合。采用比较法进行了混料均匀性的测定,数理统计分析表明,该混科器具有良好的混合效果。     

承钢150m^2烧结机布料系统改造

介绍了布料系统改造前存在矿槽斗堵料、五辊布料的偏析性、透气性差、易掉辊、松料器的形状和布置不合理以及无压料器等问题。采取把称量斗和下部漏斗合并为一个斗、改五辊布料为九辊布料，改进联轴器、重新布置松料器、增加压料器等措施。解决了布料系统存在的问题，取得良好使用效果。     

斜面式三通分料器的设计及应用

通过分析翻板式三通分料器的结构及使用中存在的一些缺点 ,介绍了斜面式三通分料器的设计和应用效果。     

梅山烧结厂使用双层松料器的效果

梅山烧结厂为了强化烧结,采用了双层松料器以提高料层透气性.本文介绍了该松料器的特点及其使用效果.     

水平松料器对烧结料层中气流分布的影响

本文通过实验室冷态实验研究，分析了水平松料器对烧结料层中气流分布的影响。试验结果表明，水平松料器在横向（水平）４倍于其尺寸左右的有效范围内改变了料层中的气流分布，气流速度增大。这有助于水平松料器的合理布置与应用。     

高炉炉顶布料器的故障及检修

介绍了沙钢380m^3无料钟炉顶的布料器常见故障，提出各类故障的解决方法及检修注意事项，对布料器的局部改进提出建议。     

节能型落矿回收控制方法在卸船机的应用

介绍目前卸船机较为普遍的落矿回收方式,并以马迹山港一期卸船机为例分析了其运行过程,指出了系统存在的缺陷和不足。针对这种具有落矿回收功能的卸船机存在的能源浪费问题,提出一种基于单片机和PLC交互控制的节能型落矿回收控制方法。介绍该控制系统的技术方案、四个主要组成部分的硬件改进设计以及系统相关软件控制流程,并作了运行分析。分析显示,新系统在灵活性、可控性以及节约费用方面均有了很大改观,实现了落矿回收自动化与节能目的。     

5200KW同步电机无刷励磁装置

阐述了无刷励磁装置的结构,恒功率因数控制,恒励磁控制,速度反馈控制系统及ＰＬＣ技术在励磁装置中的应用。     

原料对低铜电刷导电性能的影响

以电解铜粉和天然石墨的混合粉为原料,采用压制、烧结工艺制备电刷试样,研究电解铜粉松装密度和石墨粒度对低铜电刷导电性能的影响,并与以铜包石墨粉为原料制备的电刷进行对比.用SEM观察粉末和试样的形貌,用电碳制品电阻率测试仪测定试样的电阻率.结果表明:以混合粉为原料制备的电刷,当铜含量w(Cu)为30％时,随着电解铜粉松装密...     

Processes and Equipment for the Preparation of Coke Pitch and Graphitoplast Compositions for Pressing of Intermediate Products for Electrical Engineering

Metallurgist - This article discusses advanced developments in the field of manufacture of electrical machine brushes. A new method for manufacturing by mixing coke pitch and graphitoplast...     

Toothbrushing force in relation to plaque removal

This was a 2-part study. The purpose of the 1st part was to examine the relationship between brushing force and plaque removal efficacy comparing a regular manual toothbrush (M) with an electric toothbrush the Braun/Oral-B Plak Control (B). The study consisted of a single oral prophylaxis followed by 5 experiments which differed solely in respect to toothbrushing force. At baseline (after 24-h plaque accumulation), the amount of dental plaque was evaluated and subsequently, the subject's mouth was brushed by a dental hygienist. Brushing was carried out in a random split-mouth order. Either the 1st and 3rd quadrants or the 2nd and 4th quadrants were brushed with 1 toothbrush and the 2 remaining quadrants with the other. The available time for the brushing procedure was 2 min. After brushing, the amount of remaining dental plaque was assessed. The force used in experiment 1 through 5 was 100, 150, 200, 250, 300 g, respectively. The results show that when brushing force is increased, more plaque is removed with either of the two brushes. Except for the high brushing force (300 g), the electric toothbrush removed more plaque than the manual brush. The purpose of the 2nd part was to evaluate the habitual brushing force which individuals use with various toothbrushes. Besides a manual toothbrush (M), 3 electric toothbrushes were examined, the Rotadent (R), Interplak (I) and Braun (B). 20 subjects were selected on the basis of being 'good brushers' (plaque score at screening < 25%). At baseline, each subject randomly received 1 of the 4 brushes. They were allowed a training period of 3 weeks at the end of which they were asked to abstain from brushing for at least 24 h. The plaque (Turesky modification of the Quigley & Hein) was scored, after which the subjects brushed their teeth (2 min) with the assigned toothbrush equipped with a strain gauge. A computer set-up measured (100 Hz) and calculated the mean brushing force. After brushing, the amount of remaining plaque was assessed. The design of the study was a 4-way cross-over. The results show that with a manual brush, considerably more force is used than with the electric brushes (R = 96, I = 119, B = 146, M = 273). No significant relation between brushing force and plaque removal was demonstrated for any of the brushes.     

Tripeptide growth hormone secretagogues

The purpose of the present study was to compare in untreated patients suffering from moderate to severe periodontitis the efficacy of dental floss (DF) and interdental brushes (IDB) in the reduction of plaque, gingival inflammation, and probing depth in a 6-week period prior to subgingival debridement. Twenty-six patients (12 female, 14 male; mean age 37.4 years; range 27 to 72 years) were instructed to use DF for one side of the dentition and IDB for the other side as an adjunct to the daily toothbrushing for 6 weeks. Oral hygiene instructions for toothbrushing and the use of the two devices were given at baseline and at week 3. Measurements were carried out at baseline and at 6 weeks including plaque scores, probing depth, and 2 bleeding scores (periodontal pocket bleeding index and angulated bleeding index). With the IDB, the approximal plaque score at baseline of 3.09 reduced to 2.15 at 6 weeks and with DF from 3.10 to 2.47, respectively. IDB proved to remove significantly more plaque than DF. Baseline probing depth of 5.84 mm for IDB sites and 5.59 mm for DF sites was reduced to 5.01 mm at 6 weeks for both regimens. Analysis showed that the use of IDB resulted in a greater pocket reduction. Both bleeding indices were slightly reduced with IDB and DF, but no differences between devices were found. In relation to patient acceptance, more problems were observed with DF, and IDB were felt to be more efficacious. In conclusion, the results of the present study indicate that in combination with a manual toothbrush, the use of interdental brushes is more effective in removal of plaque and results in a larger reduction of probing depth than the use of dental floss. Although the differences were small, they indicate, in combination with patient preferences, that interdental brushes are to be considered preferable to floss for interdental plaque removal in patients suffering from moderate to severe periodontitis.     

Maintenance and treatment of the ailing and failing implant

Due to the pathologic nature of oral bacteria, the partially edentulous implant patient is at a greater risk than the fully edentulous. Peri-implantitis and/or retrograde peri-implantitis can result in ultimate loss of the implant fixture. It is important that the implant dentist understand the difference between the ailing implant, the failing implant, and the failed implant. This article discusses the pathologic diseases that affect dental implants and how to treat the "infected" implant (degranulation and detoxification) for titanium and hydroxylapatite-coated implants. Implant maintenance, including hand or motorized brushes, flosses, and oral rinses (chlorhexidine, 0.2%) will also be presented.     

Friction plating of metal on metal. Part II. Mechanism of friction plating

Experiments were performed on mono-and polycrystalline materials to study the mechanism of friction plating as a combination of plastic deformation of the surface layer of the substrate and the formation of a coating when the coating is applied with a flexible tool (the bristles of rotating metal brushes). The study determined the effect of the material and the initial preferred orientation of the substrate on its strain-hardening and the texture obtained in the treatment, as well as the effect of the substrate on the same characteristics for coatings of materials having different physical and crystallographic properties.     

Metal-on-metal friction plating

The most expedient method of applying metallic coatings is friction plating with the use of rotating wire brushes (RWB). The coating metal is pressed against the bristles of the RWB and heated to high temperatures in the contact region. Particles of the coating metal are then captured by the ends of the bristles and transferred to the surface of the product being coated. The surface layer is simultaneously subjected to plastic deformation. The article presents the main parameters of the process and describes its ranges of application.     

Thermomechanical properties of electric brush materials produced from Teflon-lead metallic polymer and graphite powders

Conclusions Metallic polymer powders have been obtained which can be employed, with various carbon component additions, as starting materials for the production, by hot pressing, of electric brushes. A study was made of the thermomechanical properties of various electric brush materials of this type. The best properties were found to be exhibited by lead + Teflon + graphite metallic polymers produced by simultaneous heat treatment and subsequent hot pressing at 150°C.Translated from Poroshkovaya Metallurgiya, No. 11(203), pp. 43–47, November, 1979.