Frames described as suitable for fixed or opening fanlights are to have transomes of similar steel with welded seams at edges and ends tenoned into and welded to frames.

  • 被描述为适于固定或开启扇形窗的框架须和开榫和框架焊接的边缘和端部的焊缝采用同样的钢材。
目录 查词历史