大型铸钢件水玻璃自硬砂应用研究

1990年机电部下达我厂“大型铸钢件水玻璃自硬砂应用研究”课题任务(编号——892A1009),本文是该课题的生产验证报告,同时,本文还归纳了本厂自1984年以来,在水玻璃砂酯硬化新工艺方面所做过的工     

水玻璃砂的发展概况

本文概述了水玻璃砂工艺的发展。与有机粘结剂砂相比,水玻璃砂具有许多优点。到目前为止,它仍是国内铸钢件生产厂家的主要粘结剂,虽其使用工艺还处在落后状态,但在水玻璃砂工艺不断发展的今天,没有理由一定要用树脂砂代替水玻璃砂。     

铸钢砂芯用酯硬化水玻璃砂新工艺

铸钢砂芯用酯硬化水玻璃砂新工艺沈惠珍１概况我厂八车间自六十年代初期建成投产以来，一直以传统的粘土烘模砂工艺为主来制作砂芯，生产效率低，扬尘大，能源消耗高，铸件尺寸偏差大，热裂缺陷多。这种少、慢、差、费的工艺早已适应不了我厂汽轮机生产发展的需要。为了改...     

有机酯水玻璃自硬砂的性能探讨与应用

本文重点阐述了以硅砂为原砂,MDT有机酯系列作硬化剂的水玻璃自硬砂合适的水玻璃加入量,各有机酯品种及其不同加入量对型砂性能的关系,环境温度对型砂自硬速度的影响,型砂可使用时间和可脱模时间,自硬后的存放性,以及残留强度等试验结果。并介绍了用锆砂和铬铁矿砂等特种砂配制酯硬化水玻璃砂时的基本配方及性能。最后介绍了酯硬化水玻璃砂的生产应用实例及其效果。推荐的酯硬化水玻层砂的基本配方是:a.硅砂100,水玻璃2.8～4.5,MDT有机酯占水玻璃的8～12％;b.锆砂100,水玻璃1.5,MDT有机酯0.5～0.20;c.铬铁矿砂100,水玻璃1.6～1.8,MDT有机酯0.16～0.22。     

特大模数深层渗碳硬齿轮的加工

针对我厂现有磨齿机的设备和对特大模数齿轮参数分析制定出特大模数硬齿轮加工工艺方法。     

酯硬化水玻璃自硬砂的研究及在铸铁件上的应用

酯硬水化玻璃自硬砂是一种新的造型材料，在对近１０００试样进行８０余次试验的基础上，对酯硬化水玻璃自硬砂作了较系统的研究，并实际浇注了一批铸铁件，实践证明，水玻璃加入量低，解决了水玻璃砂的溃散问题，强度高、含水量低、硬化速度和可使用时间可通过不同种类的有机酯调整，效果良好。     

水玻璃类浆液灌入砂土层的渗流规律研究

水玻璃类浆液作为化学灌浆材料,其粘度在随时间变化．因此浆液在砂土中的渗流过程较复杂。首先在达西定律的基础上推导出化学浆液在砂土中的渗流公式,然后采用品氏毛细管粘度计对浆液的粘度进行测定．通过曲线拟合回归总结出浆液粘度随时间变化规律,最终得出浆液在砂土中的渗流规律。     

特殊模数蜗杆的车削

我厂是生产冶金轧制成套设备的企业,按照轧钢生产工艺排列的加热、轧制、精整及辅助机械称为轧钢机械,轧钢机械分为主机和辅助设备。主机由主电机、主传动、工作机座三部分组成。轧钢机主机座由机架、轧辊、轧辊轴承和轧辊调整及平衡机构组成。调整机构主要有轴向调整机构和径向调整机构。     

大模数电铲齿轮轴沿齿沟中频淬火

通过对２８００ＸＰ电铲设备中径节３／４（即模数３３．８）齿轮轴沿齿沟中频淬火三要素（即感应器的设计制造、加热工艺、冷却工艺）的试验研究,设计并制作出合理的感应器,确定了最佳的工艺参数。经试制,沿齿沟淬火硬度和淬硬层深均匀分布,完全达到了Ｐ＆Ｈ公司的技术要求,实现了大模数重载齿轮轴沿齿沟中频淬火的国产化。     

天然气马蹄焰水玻璃窑的节能优化设计及应用

介绍了蓄热燃烧和烟气余热回收技术在天然气马蹄焰水玻璃窑中的应用,通过实际项目的建设及运行分析,总结了天然气马蹄焰窑的一些设计经验和运行数据。     

浅谈对玻璃电熔窑设计的一些看法

简述了玻璃电熔窑的优点，分析了小型电熔窑的结构，列举了各种电极的特点，提出了布置电极、分配电能的一般原则，简述了选择耐火材料的目的和确定电极间玻璃液电阻的方法。     

Fast-neutron and gamma-ray transmission method for coke-humidity determination

Efficient and highly automated metallurgical processes require the on-line control of coke moisture which assures high steel quality and fuel economy. The present paper dealt with the feasibility study of the Fast Neutron and Gamma-ray Transmission (FNGT) technique for the determination of the moisture content of coke in a hopper-mounted gauge arrangement. In the experimental assembly, a Pu–Be source was used. Two separate detectors: φ25×120 mm ³He (surrounded by paraffin moderator) and φ100×100 mm NaI(Tl) were applied. The temperature of the moderator was controlled and a suitable correction of the neutron count rate was done as the hydrogen H capture cross-section shows a 1/v dependence, where v is the neutron velocity. The optimisation of the FNGT arrangement was done by the modelling calculations using MCNP 4C code and was focused on obtaining a high sensitivity of the transmitted neutron flux to the moisture changes and on lowering the neutron-counting error, both leading to a more accurate humidity determination. Laboratory measurements were carried out for lump-coke and crushed-coke samples, with added moisture up to 8 wt.% and 17.1 wt.% respectively, and showed a good agreement between the moisture content determined from the FNGT measurements and the moisture determined from an oven-drying method.     

Water profile determination in a running PEMFC by small-angle neutron scattering

The water management in an operating polymer electrolyte fuel cell was studied by small-angle neutron scattering (SANS). The experiments were conducted at 80 °C under pressure (1.5 bar) using non-humidified gases and porous gas distributors. The parameters under study were the gas distributor porosity, the membrane thickness, the nature of the electrodes and the gas flow. SANS is shown to be a powerful technique to determine in situ the amount of water in the cell, to differentiate the water located within and outside of the membrane and its distribution across the membrane thickness. The data analysis leads to the determination of water concentration profiles across the membrane that could be used to validate mass transfer models. It is shown that a significant current can be extracted with a dry membrane, porous gas distributors and dry gases and that the membrane does not significantly swell whatever the electric load.     

Water: A critical resource in the thermoelectric power industry

Water availability represents a growing concern for meeting future power generation needs. In the United States, projected population growth rates, energy consumption patterns, and demand from competing water use sectors will increase pressure on power generators to reduce water use. Water availability and use also exhibit strong regional variations, complicating the nature of public policy and technological response.     

某玻璃厂节能措施初探

通过对湖北广水玻璃厂窑炉的热工测试,进行了热量收,支平衡计算,得到各窑炉的能耗状况,并找出节能方向,提出几点建议;实践中初步取得成就。     

玻璃丝布表面处理炉的设计

介绍玻璃丝布表面预烘,固化炉炉型结构以及对卧式炉与立式炉两种炉型进行比较。     

A method for the ad hoc and real-time determination of the water balance in a PEMFC

A novel method for the ad hoc and real-time determination of the water balance in a proton exchange membrane fuel cell is presented. The method requires the anode side of the fuel cell to be operated in open-ended mode and to use dry, pure hydrogen as is typical for vehicular applications. In that case there is a linear relationship between the anode outlet velocity and the effective drag coefficient of water through the membrane, r_d, provided the stoichiometric flow ratio is sufficiently low (below ξ = 1.2). The anode outlet velocity can then be directly measured e.g. by using hot wire anemometry, and this method provides a voltage signal that can be fed to the board computer of a fuel cell vehicle for PEMFC diagnosis. It is also shown that the nitrogen cross-over from cathode to anode has only a small effect on the anode outlet velocity. In addition to detecting the velocity, the relative humidity may be measured which is shown to be independent of the current density, but measurement techniques suffer from lower accuracy. It is argued that this method can also be applied to quantify fuel cell degradation. Finally, it is fundamentally shown that when operating the fuel cell in steady state mode at a hydrogen stoichiometric flow ratio as low as 1.03, the molar fraction of hydrogen in the gas mixture at the anode outlet is at least 50% which means that at steady state there will be no hydrogen starvation at the anode outlet.     

125I粒子条剂量分布研究

【摘要】 目的 探讨连续线状排列125I粒子条剂量分布。方法 通过玻璃剂量计及IP板测量粒子条剂量立体分布并与计算软件结果比较。结果 玻璃剂量计测量数据与软件计算相关性良好（r > 0.99,P = 0.000）。除R = 0.5 cm处外,两者差异性无统计学意义（P < 0.05）。IP板测定2 cm以内粒子间存在自吸收现象,自吸收的量约22.8%。结论 连续线状排列的125I粒子条辐射等计量分布类似于柱形体,为其应用于腔内放射治疗提供理论依据。
     

玻璃幕墙建筑节能措施探讨

本文分析了室内气流速度、设置外遮阳、幕墙朝向、玻璃类型和玻璃夹层的填充气体等因素对玻璃幕墙建筑能耗的影响。结果表明,提高室内气流速度、在建筑室外种植树木或设置外遮阳、合理的玻璃性能组合是玻璃幕墙建筑夏季节能的有效措施。