In the design of circular arc fixed window, because the radian of curved arc glass and the radian of the frame are very difficult to match, special circumstances should consider the design for the outside of the rubber seal.  

When the plastic window design aluminium frame and frame are spliced up and down, the splicing screws in the design should be connected from bottom to top to avoid the nail head on the upper side and rain or dew invading the lining steel cavity, resulting in corrosion of the lining steel.