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Application Analysis of Aluminum Frame and Aluminum Frame
One, steel box form
Doors and windows steel box, that is, before the installation of aluminum alloy frame, the first installation specifications for the 40 * 20 * 2 (according to different specifications of the different specifications) rectangular square steel frame (diameter than the window frame size slightly larger), and other civil facades After the completion of the construction of the aluminum alloy doors and windows frame installed in the sub-frame, in order to facilitate the construction of external walls of construction, to avoid the installation of doors and windows and civil construction cross.
Generally need 20 * 40 * 2 specifications of the hot galvanized square tube
