(一一七)钢精轧头敷线为什么常坠落?钢精轧头又称铝皮卡子。塑料护套线用钢精轧头敷线在一般性民用建筑中经常采用。但也常发现,没过一、两年,敷设在天花板或墙面上的导线,连同作固定用的钢精轧头及小钉子一起坠离开来。经调查分析,造成坠离的主要原因是,施工时没有严格按照操作工艺执行:(1)固定钢精轧头的钉子用细脚圆钉,不是鞋钉;(2)在 (117) Why do the steel rolling heads fall? Steel finishing heads are also called aluminum pickups. Steel sheathed wires for plastic sheathed wires are often used in general residential buildings. However, it is also often found that in less than one or two years, the wire laid on the ceiling or wall has been dropped along with the steel head for fixing and small nails. After investigating and analyzing, the main cause of the fall is that the construction did not strictly follow the operation process: (1) The nails used to fix the steel finishing head were nailed with pins, not shoe spikes; (2)