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信号电缆在五十年代使用的是一机部标准及生产的PZQ_2型油浸纸绝缘铅包铠装麻被电缆。由于制造复杂施工困难,于五十年代末停产。六十年代初,采用一机部标准生产的PVV_2型聚氯乙烯绝缘及护套铠装信号电缆。由于聚氯乙烯材料的介电常数大及透潮率较高等缺点,已由铁道部公布的聚乙烯绝缘聚氯乙烯护套内钢带铠装的PYV_(29)型电缆代替。以后曾生产过PVVG型聚氯乙烯绝缘及护套改良型电缆,芯径改为0.8毫米。由于宝成电气化铁路的需要,又曾生产过PVL_(11)及PVL_(22)型有铝护套聚氯乙烯绝缘信号电缆。其后又
The signal cable used in the 1950s was a machine-standard and produced PZQ_2 oil-soaked paper-insulated lead-clad armored sheathed cable. Production was discontinued in the late 1950s due to complex construction. The early sixties, using a machine-standard production of PVV_2 PVC insulated and sheathed armored signal cable. Due to the large dielectric constant and high moisture permeability of PVC materials, it has been replaced by PYV (29) type steel tape armored polyethylene insulated PVC sheathed cable published by the Ministry of Railways. After PVVG PVC insulated and sheathed modified cable has been produced, the core diameter to 0.8 mm. Due to the need of Baocheng Electrified Railway, PVL_ (11) and PVL_ (22) PVC insulated signal cables have been produced. Then again