软件翻译不评分！！！

近期翻译的都是关于电缆的发展史，国内相关的资料比较少，在此分享给大家。

读英文吃力的朋友，可以等翻译出来后，再读！！

另外，大家翻译时，最好校验一下，便于朋友们理解。

1.8 TROUBLE IN PARADISE

During the mid-1970s,reports of early cable failures in extruded dielectric systems began to bedocumented in many parts of the world. “Treeing” was reintroduced to the cableengineer’s vocabulary. This time it did not have the same meaning as withpaper-insulated cables. See Chapter 17 for additional information on treeing.

By 1976, reports from utilities [4] and results of Electric PowerResearch Institute (EPRI) research [5] confirmed the fact that some thermoplasticpolyethylene insu-lated cables (HMWPE) were failing in service in less than 5years and failures were occurring at a rapidly increasing rate. By 1980,production of medium voltage HMWPE ceased in North America.

XLPE exhibited a much lower failure rate which was not escalatingnearly as rap-idly. Data from Europe confirmed the same facts in a reportprepared by UNIPEDE-DISCAB. XLPE had been commercially available since 1963,but its slightly higher first cost had confined its use to the heavier loaded feedercables. XLPE became the medium voltage insulation of choice by 1977.

The realization of the magnitude and significance of the problemled to a series of changes and improvements to the primary voltage cables:

? Research work wasinitiated to concentrate on solutions to the problem

? Utilities began replacingthe poorest performing cables

? Suppliers of componentmaterials improved their products

? Cablemanufacturers improved their handling and processing techniques

1.8从天堂到地狱

在20世纪70年代中期，在世界各地都有报道挤出绝缘电缆失效。“树”的概念走进了电缆行业。这个和以前纸绝缘的“树”不是一个意思。请在17章查看更多关于“树”的内容。

到了1976年，EPRI确定，HMWPE服务不足5年，就可能出现绝缘失效，5年之后，失效的概率会急剧增加。到了1980年，HMWPE绝缘的中压电缆在北美被淘汰。

与此同时，XLPE的表现要好很多，绝缘失效的概率比较低，而且也不会随着时间快速升高。欧洲的数据也证实了同样的情况 。自从1963年，XLPE绝缘的电缆已经实现了商业化，但是它的价格要略高一些。所以当时XLPE绝缘的电缆一般用在较高负荷的地方。到1977年，XLPE成为了中压电缆绝缘的首选。

重大的题的发现，在高压电缆领域，引发了一系列的改变和改进:

为解决问题而开启调查工作。

公共事业部门开始更换表现不好的电缆。

原料供应商开始改进原材料。

电缆制造商开始改进电缆工艺