不排放冷却液净化技术

我国机械行业每年排放冷却液数亿吨 ,价值数千亿元 ,报废的冷却液须集中油水分离后排放 ,但溶液中含有的表面活性剂、防腐败剂进入自然环境中不能降解 ,造成二次污染 ,且生产成本大大提高。为此 ,我们研制出了不排放冷却液净化设备。该设备可连续进行固液分离 ,定期灭菌 ,冷却液可实现零排放。过滤精度为 1 5以上 ,灭菌率达到 99.95% ,1 0～ 30 min即可完成灭菌过程 ,适用于各类磨床、电火花线切割机床的工作液过滤、灭菌 ,一般金属切削机床也可应用。对环境保护和材料节约有重要意义。信息索引号码 40 3西安工业学院机械系　　范植坚电话 :…     

轴承零件磨加工冷却液的综合循环系统

目前，轴承零件磨加工时，冷却液消耗较快，同时产生大量含有金属屑、磨料和砂轮结合剂的泥渣，虽经过滤设备净化，但效果不好，既影响加工质量又污染环境。采用冷却液综合循环系统后，改善了磨加工质量，节约了冷却液，提高了环保水平，获得了较好的经济和社会效益。附图3幅，参考文献3篇。     

一种机床用冷却液过滤装置改进设计

本设计针对现有机床冷却液过滤装置存在的不足及问题,对该冷却液过滤装置进行改进,改进后能使喷溅出来的冷却液在进入冷却循环系统之前,通过滤网过滤,有效防止切屑碎片进入冷却循环系统造成故障,保证冷却循环系统可持续正常使用。     

信息与动态

俄罗斯格斯汽车厂采用先进冷却液“格斯”汽车厂经常在寻找、研究和采用具有稳定性、耐生物性、抗腐蚀性和生态洁净的冷却液。在机械加工中广泛采用半合成的冷却液,以替代低效乳浊液。在采用工业浓缩物的同时还利用废油过滤后的油基乳浊液。由于正确选择了一组乳化剂、腐...     

轴承生产中工作液的过滤方法及相应设备

对单机循环过滤及集中循环过滤方法在磨削冷却液、超精研磨液及煤油清洗液过滤中的应用作了介绍,分析了过滤原理和优缺点,指出了过滤设备的发展方向。     

一种简易可靠的冷却液过滤水箱

我厂曲轴磨床和凸轮磨床加工的都是球铁件,原水箱的过滤性能不能适应球铁件的要求,一般三天要更换一次冷却液,在粗磨凸轮时甚至每天都要更换。我们做了一个如图所示的冷却液过滤水箱,改用这个水箱后,以M 8325凸轮磨床为例,过去每天换一次水,现在14天换一次(中间加一次水),这样每月可节约皂化油价值220元。带有铁屑的冷却液首先流入I槽,大量铁屑沉淀下来,少量细微杂质由     

精密加工冷却液过滤技术及其最新发展

阐述了精密加工中冷却液及其过滤的重要性，并介绍了过滤精度的测定及常用过滤方法。     

发动机冷却液的使用

针对发动机冷却液使用不当导致其故障经常发生,根据发动机结构特点和工作原理,结合工作实践,提出了行之有效的发动机冷却液的加注、更换及排放方法。     

冷却液负压过滤机集中过滤系统分析

集中过滤系统及其附属装置放置在给定区域内的地面上。其集中冷却过滤系统的过滤形式:磁性排屑机+真空负压纸带过滤机+反冲洗过滤的过滤方式,可延长冷却液使用寿命,提高产品加工质量,降低刀具磨损,提高生产效率,切屑自动排除,实现车间文明生产,降低工厂运行成本。并对系统排出的切削进行甩干处理,回收乳化液。对切削甩干废液和过滤带反冲洗乳化液采用纸带过滤机过滤后返回系统。     

精密镟磨(二)

润滑冷却液的选用润滑冷却液在镟磨过程中,具有特殊重要的意义。镟磨表面的质量的是否优良,绝大部份是取决于润滑冷却液的质量与数量的选择得是否正确。润滑冷却液必须是十分清潔,不能夾杂其他铁屑等杂质;所以润滑冷却液在应用过程中必须经过严格的清屑过程。最有效的方法,除经过沉澱过滤外,还经过一道磁力去屑的设备,以确保润滑冷却液的纯潔。润滑冷却液必须充分地、均匀地、而且要连续地注射在工件的表面。一般应用上应不小于每分钟20至35公升,并且也要保持一定的黏度,来足够满足工件表面与油石间的润滑,一般常用的为1.8至2.4(安格尔氏)。     

运行参数的动态控制对100 kW燃料电池系统效率及稳定性的影响

质子交换膜燃料电池运行过程中的功率输出,电流、电压输出,运行温度,向燃料电池输送的燃料氢气及氧化剂空气的流量、温度、湿度,冷却流体温度等运行参数之间可实现动态关联控制,对提高燃料电池运行效率及稳定性有重大影响。当燃料电池发电系统由怠速状态转向输出状态时,要求向燃料电池供应的燃料氢气、空气、冷却流体的流量也发生变化,并对其他运行参数(例如湿度、温度)实施动态控制,不但满足燃料电池功率输出变化的要求,而且可以达到提高燃料电池发电系统自身的燃料效率与运行稳定性的目的。     

屏蔽电机屏蔽套电磁力仿真分析

屏蔽电机泵中屏蔽套为关键部件之一,起物理隔离作用,其完整性对一回路的安全运行有着重要的影响。屏蔽套安装在主泵电机内,受到交变磁场、冷却剂流场等因素的综合作用,载荷条件复杂。通过屏蔽电机内电磁场的谐波分析,得到磁感应强度分布规律和作用于屏蔽套的电磁力分布规律。结果显示,在铁芯范围内沿电机圆周方向屏蔽套所受电磁力呈周期分布,以切向力为主,且定子屏蔽套所受电磁力大于转子屏蔽套;从铁芯指向绕组端部,屏蔽套所受电磁力逐渐减小,离开铁心端面对应的轴向位置后,减小速率最大。     

BTA深孔钻射流孔参数的优化与仿真

针对射流孔几何参数对BTA深孔钻喉部流场的影响,对射流孔直径、角度与射流孔距离喉部的位置进行有限元数值模拟,提出一种最优的新型喉部结构。在设置有限元模型的湍流强度和耗散率基础上,进行不同几何参数的深孔钻头喉部结构的排屑能力对比试验,测量冷却液系统的冷却液出口断面流出平均速度。试验结果表明:最优喉部结构为∅38mm BTA深孔钻头所组成的冷却系统,冷却液出口断面流出的平均速度提高9.6%,同时提高了冷却液系统整体的排屑能力。由相似定理得出,冷却液系统的排屑能力提高9.6%。     

蒸汽发生器传热管衬管技术研究

核电站蒸汽发生器是将反应堆的热能传递给二回路介质以产生蒸汽的热交换设备,其运行的可靠性直接关系着核电站的安全性与经济性。蒸汽发生器传热管的泄漏将导致放射性物质释放到二回路,甚至排放到大气中,造成严重的放射性污染。总结了国外各种衬管技术及其在核电站的实际应用,根据核电站反馈的经验概述了各种衬管技术的优缺点,在此基础上,研究了适用我国实际情况的衬管技术,并进行了试验。该衬管技术融合了液压胀接、钎焊和钨极气体保护焊技术,具有重要的实用意义。     

Heating performance characteristics of stack coolant source heat pump using R744 for fuel cell electric vehicles

The objective of this study is to investigate the performance characteristics of a stack coolant source heat pump using R744 with a stack coolant heat source for fuel cell electric vehicles under cold weather conditions. Electric heaters are currently used in fuel cell electric vehicles, and the high levels of energy consumption involved lead to lower fuel efficiency and a reduction in the vehicle??s driving range. In order to improve the efficiency of the fuel cell electric vehicles in this study, a heat pump using R744 as a refrigerant and making use of wasted heat from the stacks is developed to cover the heating capacity. This heat pump is tested and performance optimized for stack coolant heat recovery under the compressor speeds, air temperatures, and flow rates of the interior heat exchanger, as well as the coolant flow rates of the CO₂-coolant heat exchanger. In addition, the heating capacity of the tested system was sufficiently attained over 5.0 kW at the coolant flow rate of 5.0 l/min under extremely cold weather conditions of ?20°C.     

Study on grinding of LiTaO3 wafer using effective cooling and electrolyte solution

As a typical multi-functional single crystal material, lithium tantalate (LiTaO₃ or LT) exhibits its excellent electro-optical, piezoelectric properties and has now been widely applied into many applications, such as electro-optical modulators, pyroelectric detectors, optical waveguide, piezoelectric transducers and SAW (surface acoustic wave) substrates. LT is known as a very important functional material, however the details of its machinability are not readily available yet. The content in this study is firstly focuses on the physical properties of LT like piezoelectric and pyroelectric effects and their influence on grinding performance. The obtained results are analyzed and discussed to understand its physical properties which have significant influences on their machinability in the grinding process. The crack initiation is possible to be dominated by internal stress which originated from self-polarization of the material itself. Hence, in order to suppress the physical effects induced by polarization during grinding of LT, control the temperature of coolant and increase the electrical conductivity of coolant are purposely tried in this study. The grinding results suggest that control of coolant temperature and use of electrolyte solution can effectively suppress the increasing rate of grinding torque and surface roughness, which in turn enhance the performance of LT wafer grinding. The LT wafers are eventually able to be thinned less than 100 μm.     

Development of a pressurized internal cooling milling cutter and its machining performance assessment

In view of the serious problem of milling heat in milling nickel-based superalloys Inconel 718, this paper investigates the heat transfer performance of internal cooling in end milling Inconel 718, and the superiority of internal cooling milling cutter's heat exchange ability during processing is explored. The flow field characteristics of cutting fluid and milling temperature are studied by Computational Fluid Dynamics (CFD) and Finite Element Method (FEM). Compared with external flood cooling, the principle of internal cooling with excellent heat transfer performance is explained and the influence of coolant pressure on lubrication performance is analyzed. Experiments for end milling of Inconel 718 under different cutting speeds and cooling conditions have been carried out. The results indicate that the simulated and measured temperatures showed an acceptable agreement. The internal cooling has better heat transfer performance compared with flood cooling. With the increase of coolant pressure, the heat exchange efficiency is gradually enhanced. When the coolant pressure rises from 2 bar to 10 bar, the milling temperature at the measured point inside the workpiece reduces by 27.55 °C, the surface roughness reduces by 12.0%, the surface residual compressive stress increases by 68.37 MPa and better surface morphology is obtained. Besides, in the experimental range, with the increase of cutting speed, milling temperature increased, the pile-up effect on the sides of scratching was weakened and better machined surface integrity was found.     

Enhancement of combined cycle performance using transpiration cooling of gas turbine blades with steam

Gas/steam combined cycle is synergetic combination of Brayton cycle based topping cycle and Rankine cycle based bottoming cycle, which have capability of operating independently too. Combined cycle performance depends on the constituent cycles and it can be reasonably improved by enhancing gas cycle performance using gas turbine blade cooling. Amongst different cooling techniques the transpiration cooling offers effective utilization of coolant as compared to film cooling because of better shrouding of blade surface as the coolant is discharged from entire blade surface. The present work deals with evaluation of performance enhancement of combined cycle by using steam transpiration cooling of gas turbine blades. The combined cycle performance parameters e.g. overall efficiency and specific power output etc. have been compared for air transpiration cooling and steam transpiration cooling. The results revealed that for the specified conditions the steam is superior coolant in comparison to air and the combined cycle performance can be enhanced by applying transpiration cooling in gas turbine blades with steam as coolant. With a turbine inlet temperature of 1800 K and compressor pressure ratio of 23, the combined cycle efficiency with steam transpiration cooling of gas turbine blades is higher by 1.94 percent approximately as compared to the efficiency of combined cycle with air transpiration cooling of gas turbine blades.     

储能飞轮过盈/脱落过程研究

核电冷却剂泵上安装飞轮,用以储备转动惯量,保证在泵电动机断电时冷却剂流量缓慢下降,避免反应堆事故。采取过盈配合的目的是控制飞轮临界转速。过速情况下,飞轮发生膨胀,从立轴脱落,可以预防爆裂的发生。设计了一套由临界转速控制的逐层脱落的安全飞轮。运用平面应力法与包含间隙元的有限元模型,对飞轮进行过盈设计和应力分析。在递增的离心力作用下,对飞轮摩擦配合的连续、滑动、脱落过程进行完整仿真。     

大型有源相控阵雷达阵面管网仿真及优化

采用一维流体仿真分析软件对大型有源相控阵雷达阵面的液冷管网系统进行了仿真分析及优化。首先建立管网模型,利用试验数据确定阻力元件的性能参数,对阵面管网进行了仿真分析,计算得出在额定流量下,各种管径对流量分配差异的影响,从而确定管网的最佳管径。同时,也得出了管网的阻力特性。通过管网的仿真及优化,可释放液冷系统研发风险,节约研发成本,其优化方法和优化结果对其他阵面管网设计也可起到重要的指导作用。