1
軟件翻譯不評分�。�！
近期翻譯的都是關(guān)于電纜的發(fā)展史，國內(nèi)相關(guān)的資料比較少，在此分享給大家。
讀英文吃力的朋友，可以等翻譯出來后，再讀��！
另外，大家翻譯時，最好校驗一下，便于朋友們理解。
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
2
1.8從天堂到地獄
在20世紀70年代中期，在世界各地都有報道擠出絕緣電纜失效�！皹洹钡母拍钭哌M了電纜行業(yè)。這個和以前紙絕緣的“樹”不是一個意思。請在17章查看更多關(guān)于“樹”的內(nèi)容。
到了1976年，EPRI確定，HMWPE服務(wù)不足5年，就可能出現(xiàn)絕緣失效，5年之后，失效的概率會急劇增加。到了1980年，HMWPE絕緣的中壓電纜在北美被淘汰。
與此同時，XLPE的表現(xiàn)要好很多，絕緣失效的概率比較低，而且也不會隨著時間快速升高。歐洲的數(shù)據(jù)也證實了同樣的情況 。自從1963年，XLPE絕緣的電纜已經(jīng)實現(xiàn)了商業(yè)化，但是它的價格要略高一些。所以當時XLPE絕緣的電纜一般用在較高負荷的地方。到1977年，XLPE成為了中壓電纜絕緣的首選。
重大的題的發(fā)現(xiàn)，在高壓電纜領(lǐng)域，引發(fā)了一系列的改變和改進:
為解決問題而開啟調(diào)查工作。
公共事業(yè)部門開始更換表現(xiàn)不好的電纜。
原料供應商開始改進原材料。
電纜制造商開始改進電纜工藝