短语词组短语ball head insulator 球形接头绝缘子;球头形绝缘子;球头状绝缘子ball type insulator 球形绝缘子;拉紧绝缘子ball type guy insulator [电]球形拉线绝缘子insulator ball 球形绝缘体insulator ball guide 球头定位器 返回 ball insulator