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1引言近年来,微细电火花线切割加工以其独特的加工特点,即非机械接触加工,特别适合特殊复杂微小零件(如微小齿轮、微小花键、微小联接器等)加工的要求,并且具有较高的性价比,而得到了迅速的发展,在许多微型机械生产领域发挥了重要的作用。国内外对微细电火花加工技术的不断研究探索,已使微细电火花线切割加工在与微型机械制造结合及实用化方面取得了较大进步。在微细电火花线切割加工中,加工精度是主要的加工指标之一。微细电火花切割加工工具是微细线电极(以下简称电极丝),电极丝质量很小,外界轻微的振动将会引起其较大的偏移,产生形位误差,从而使加工精度很容易受到影响。在直线切割时会影响加工精度,在拐角切割时则更加严重,因此需要对形位误差进行分析,来指导微细电火花线切割加工的系统软件及自动编程软件的开关,并为自适应加工提供理论依据。2直线切割的形位误差2.1引起形位误差的原因根据微细电火花线切割加工的机理可知,在加工过程中,由于受放电力、材料蚀除过程中的爆炸力、放电通道中的瞬时压力等的影响,直线切割时,电极丝会出现与进给方向相反的滞后现象,表现为电极丝发生一定程度的弯曲,如图1所示。图中T为电极丝张力,F为加工过程中电极丝受各种作用力的... 相似文献
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一、前言数控线切割机床是加工冷冲模(凹模或凸模)的自动化机床,它由一台小型专用电子计算机自动控制,其加工精度和速度要比靠模线切割机床和光电跟踪线切割机床高,控制方式也比较先进。数控线切割机床的出现,把我国精密机械加工的水平提到了一个 相似文献
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FI 2050 TW高精度数控慢走丝线切割机床的任何一个部件都无比精密,在实现高精度、技术功能性、人机工程学以及使用方便性方面取得了卓越的成就,无论加工几克重或是几百千克重的工件,都能满足超高精度、完美一致性和超高表面质量的加工要求。其放电电源是基于CleanCut平台上,采用了全新的控制模式来实现,保证了加工表面的完美。它解决了以下几个方面的问题: 相似文献
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在快走丝电火花线切割机的应用中,为解决传统脉冲电源对放电加工的速度、精度、稳定性等方面的不利影响,以性价比较高的AT89S51单片机为脉冲电源的处理器核心,结合高频信号放大及光耦输出电路、功率放大电路等,设计了新型电火花线切割机脉冲电源系统,并完成了整机安装.实践应用表明,该系统能够较好地适应各种加工条件,使切割加工过程具有较高的稳定性和优秀加工的品质. 相似文献
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根据线切割机床的组成和工作原理,采用工控机和单片机上下位机的设计方案开发,并实现了一种线切割机床加工的电机控制系统,介绍了电机控制系统中的步进电机驱动电路,丝筒电机变频调速电路和非接触换向电路,以及与线切割加工密切相关的火花放电采样电路的软硬件设计.实践证明该电机控制系统完全满足线切割机床的加工要求,步进电机运行平稳、可靠,丝筒电机调速方便,换向稳定. 相似文献
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高速走丝线切割加工质量的改善与提高 总被引:1,自引:0,他引:1
1引言电火花线切割技术作为一种精密加工技术在电加工领域中发展迅速,它具有加工精度高、表面质量好和效率高的特点,已经成为模具制造和金属加工行业必不可少的加工手段。电火花线切割加工的原理是按照图纸上工件的形状和尺寸在计算机上作图,然后由计算机系统编译成程序(3B语言 相似文献
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The propagation of shock wave pressure in the tunnel is greatly affected by the tunnel structure, shape, material and other factors, and there are great differences in the propagation law of shock wave pressure in different kinds of tunnels. In order to study the propagation law of shock wave pressure in tunnels with different mate-rials, taking the long straight tunnel with the square section as an example, the AUTODYN software is used to simulate the explosion of TNT in the concrete, steel and granite tunnel, and study on the variation law of shock wave pressure in tunnels with different materials. By using dimensional analysis and combined with the results of numerical simulation, a mathematical model of the propagation law of shock wave pressure in the tunnel is established, and the effectiveness of the mathematical model is verified by making the explosion test of the warhead in the reinforce concrete tunnel. The results show that the same mass of TNT explodes in the tunnel with different materials, and the shock wave overpressure peak at the same measuring point is approximate in the near field. However, there is a significant difference in the middle-far fields from the explosion center, the shock wave overpressure peak in the steel tunnel is 20.76% and 34.82% higher than that of the concrete and the granite tunnel respectively, and the shock wave overpressure peak in the concrete tunnel is 24.91% higher than that in the granite tunnel. Through the experimental verification, getting the result that the maximum relative deviation between the measured value and the calculated value of the shock wave overpressure peak is 11.85%. Therefore, it is proved that the mathematical model can be used to predict the shock wave overpressure peak in the tunnel with different materials, and it can provide some reference for the power evaluation of warhead explosion in the tunnel. 相似文献
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分析了2014年中国电力供需特点,对2015年中国电力供需形势进行了预测,提出了相关措施建议。2014年受经济增长趋缓及凉夏暖冬等因素影响,中国电力消费增速和发电设备利用小时数分别为近16年和37年新低。2015年,中国电力需求增速将回升至4.0%~6.0%,全社会用电量将达到5.77万亿~5.88万亿kW?h;净增发电装机约9 140万kW,年底总装机容量将达到14.5亿kW;火电设备利用小时数进一步下降至4 638 h左右;全国电力供需总体平衡,但局部地区仍存在少量电力缺口,分区域看,华北电网地区电力供需平衡偏紧,华东、华中、南方电网地区电力供需平衡,东北、西北电网地区电力供应富余。 相似文献
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近年来,储能参与电网调峰调频辅助服务的政策层出不穷,有必要对其进行梳理与分析。本文结合电化学储能调峰调频性能与电化学储能电站运行案例,从国家、区域、省市三个层面剖析了近年来储能参与调峰调频辅助服务的政策,并归纳了典型省份对储能参与调峰调频辅助服务的准入要求、交易价格与交易模式。随后,分别从美欧储能参与调频补偿方式,以及我国主要的调频补偿方法两个方面探究了储能参与调频的补偿机制;以青海省为例,梳理了我国储能参与调峰的主要方式与补偿机制。最后,简要分析了现阶段储能参与调峰调频辅助服务的问题,从完善差异化补偿、优化储能调频调控方案、探索共享储能运营模式、完善准入及评价标准等方面对电化学储能参与调峰调频辅助服务提出了建议。 相似文献
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《The Electricity Journal》2022,35(2):107083
Tariff regulation is a fiscal method of managing economic processes with the help of taxes, requiring constant development, which is directly related to the development of the electric power industry and technological progress in general. The relevance of the study is conditioned by the need to find and implement methods for optimising tariff regulation in such an economically important industry as the electric power industry. In this regard, the purpose of the study is to identify problem areas in tariff regulation in the electric power industry, consider and analyse optimisation methods used in other countries, and reveal the positive impact of these methods on the electric power industry and the economy as a whole. The primary method in this study is a system analysis, which was used for a detailed consideration of the subject matter, with the aim of a deeper and more comprehensive understanding of tariff regulation in the electric power industry as a system with many related and interacting elements. This study also applied the following research methods: logical analysis, comparison, synthesis, deduction, and classification. The study presents the results of tariff setting mechanisms in the industry, examines the existing types of regulated prices and tariffs in the consumer electricity market, and considers the state, private, and public levels of tariff regulation in the Russian Federation. The methods of improving and developing tariff regulation in other countries, which have been successfully applied and have already shown a positive result, were also considered. The study materials are of practical value for teachers and students in the field of electric power industry, managers of tariff regulation bodies. 相似文献
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为探明在新水沙条件和人类活动的影响下赣江尾闾河网地形变化与洪季水动力特征变化的关系,以1998—2020年为研究时段,基于1998、2013、2020年河道地形,分别建立一维河网数学模型,复演赣江98特大洪水,研究不同时期地形变化对洪季水动力特征的影响。结果表明:赣江尾闾河网的整体下切使水位流量关系右移,洪期各支洪峰流量整体增加,相同水位下,外洲站来流增幅超过50%。1998—2020年期间,南支地形下切幅度大于其他各支,地形不均匀下切导致尾闾河网节点分流比改变,整体上主支与南支分流增多、中支与北支分流减少。各支流速变化剧烈,主支下游流速增幅超过1 m/s。本研究可为河道整治规划、堤坝防护和灾害预防提供一些技术参考。 相似文献
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为了拓展读者对高电压新技术及放电等离子体的视野,根据作者近期的实验结果,并结合一些他人的研究成果,对X箍缩放电等离子体及其应用进行了综述。X箍缩是以两根金属细丝作为脉冲大电流的放电负载,由于脉冲大电流磁场对等离子体的箍缩作用,在叉丝交点处将产生高温度高密度等离子体,并形成高亮度的亚ns脉冲X射线μm级点源。鉴于这两根细丝交叉并接触于一点呈"X"形状,故称之为X箍缩。X箍缩可以作为X射线源,应用于高能量密度物理领域,例如对丝阵负载Z箍缩等离子体进行背光照相,也可以应用于生物医学领域,例如对X射线弱吸收的生物体进行相衬照相。文中首先简单介绍了X箍缩工作原理及其放电发展过程;然后描述了X箍缩装置构成、驱动电流参数及其和叉丝负载质量的匹配要求;紧接着重点并详细介绍了X箍缩的X射线辐射特性;最后给出了X箍缩在X射线背光照相和相衬成像方面应用实例。 相似文献
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