共查询到19条相似文献,搜索用时 93 毫秒
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圆形的交联聚乙烯绝缘线芯在成缆时都要用填充材料填充空隙,无形中增加了电缆外径,也增加了后道工序的材料用量。如果把导体改作扇形,使扇形的绝缘线芯成缆后正好形成圆形,这样就可以大大减少缆芯的成缆填充材料,同时也降低了成缆外径,使后道工序的材料用量减少,从而降低电缆制造成本。 相似文献
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中性线芯和接地线芯分开的五芯电缆,其缆芯中的绝缘线芯通常采用四大一小或三大二小结构。为便于计算缆芯的外形尺寸和各填充空隙的截面积,通过对有关结构尺寸相互间关系的推导,获得了四大一小和三大二小的五芯电缆缆芯结构参数的图解曲线。 相似文献
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介绍了宽带市话电缆的主要电气指标;侧重描述了该电缆的制造技术的关键;保证绝缘线芯均匀一致,选择极短的对绞节距和采用层绞式单元/缆芯结构。并指出利用单模拉丝机,可以解决非连拉连韧挤塑串联生产线在挤制绝缘线芯时的导体尺寸精度难以控制的问题。 相似文献
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利用滚压轮杜绝扇形线芯成缆翻身武汉电缆股份公司孙改玲,段国权主题句:扇形线芯,成缆,工模具较大截面的三芯或四芯低压电力电缆,导电线芯一般采用扇形结构,这可大大减小电缆的直径,节省电缆护层材料,使成本降低15%~20qo,因此具有较好的经济效益。我公司... 相似文献
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<正> 绝缘线芯成缆后包绕布带,可防止缆芯在弯曲时松散或变形,以确保缆芯的圆整和紧密。因此,要求绕包带具有较高的抗张强度和较低的伸长率。过去,我厂一直使用 PVO带。但 PVO 带受季节温差的影响较大,夏季塑性增加,易被拉长,导致线芯包扎不紧密; 相似文献
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使用 D6 30单绞机对宽带数据电缆缆芯成缆绞合时 ,发现产品说明书提供的成缆节距参数与实际节距误差较大 ,为此 ,我们对该设备的成缆节距参数重新进行计算 ,并对其进行实践的验证。本文主要介绍了成缆节距的计算过程和计算结果 相似文献
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本文介绍了现代化高速话缆绝缘线芯生产线的电控系统设计,它的特点是技术先进,设计新颖,填补了国内微机在线缆挤包设备中应用的空白。从而使国产话缆绝缘线芯生产线速度快、效率高、产品质量好,跃入世界先进技术水平行列。 相似文献
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Cable installations for three-phase systems consisting of parallel single-core cable circuits carry different currents due to inductive coupling. Supplementary installed additional conductors grounded on both ends show several beneficial effects: balanced outer conductor currents, improved throughput load, and reduced current-dependent losses. With cables laid in free air, additional conductors are especially economical 相似文献
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In an ideal world, communications cabling for process control would be simple-buy all the computer, instrumentation, and electrical equipment from a single vendor, and connect it all together using a single cabling standard. But real life is never that simple; rarely are the programmable logic controllers (PLC), distributed control systems (DCS), drives, motor controls, field instrumentation, and computers all purchased from the same vendor. Supplying power to all this different equipment certainly doesn't require separate cabling structures, so why shouldn't the same be true for communications needs? Wouldn't a standard cabling infrastructure minimize the cabling infrastructure cost and complexity? The engineering group of a Canadian pulp and paper mill wondered about these two questions. They were designing a new steam plant and decided to investigate the possibility of making a single process communication cabling "utility" through the plant. The result was a design methodology that allowed a standardized cabling system to serve all communications needs throughout the process areas. Fiber-optic cable was chosen for all communications cabling outside of the control or electrical rooms. While the noise immunity and high data carrying capacity of fiber-optic cable was a factor, the primary reason was that fiber-optic cabling was the only system that could provide a single medium suitable for the very wide range of communications equipment in the mill 相似文献
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Susumu Shimamoto Satoru Murase Kenji Nishii Fuminobu Naitou Kunihiro Matsui Yoshikazu Takahashi Hiroshi Tsuji 《Electrical Engineering in Japan》2003,142(4):27-33
Pulsed field losses in a short sample (445 mm length) of 46‐kA Nb3Sn cable‐in‐conduit conductor of superconducting magnet for the fusion experimental reactor “ITER” are measured by a calorimetric method. The coupling time constant between strands is obtained as 30 ms through pulsed loss. Based on this time constant and interstrand conductance measurement, it is expected that there is a coupling current loop length of about 400 mm, which is longer than half the fabrication twist pitch in the fourth cabling stage. A geometrical calculation on several‐stage cabling shows this value to be reasonable. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 142(4): 27–33, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10088 相似文献
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随着核电厂自动控制水平的提高和数字化控制系统的引入,电子设备所处建筑物中的电磁环境也越趋复杂,无线通讯设备、大功率变频设备等的应用使得环境中高频干扰信号的比重在加大,接地设计对改善设备的电磁干扰环境起着关键的作用。将最新的IEC标准对接地和防雷保护方面的规定及工业实践应用于核电厂的接地设计,通过采用格栅形共用接地网络、电缆屏蔽层两端接地和并联接地导体等技术以改善核电厂的电磁环境,满足DCS等敏感设备的运行要求,解决核电厂在接地系统设计过程中为了满足电磁兼容要求需要重点关注的技术问题,研究成果可应用于其他类似电力工程。 相似文献