ã€China Aluminum Industry Network】 (1) The type, specification, opening direction and installation location of the windows used should meet the design requirements. (2) The installation of windows must be firm, horizontal and vertical, and uniform in height. The gap between the frame and the wall shall be filled with fullness and density, the surface shall be smooth and free of cracks, and the stuffing materials and methods shall meet the design requirements. (3) Window sashes should be flexible and free from upturns, block and rebound. Hardware accessories should be complete and correct. The seal should be in a compressed state after closing. (4) The appearance quality of the window after installation should be clean. There are no scratches, bumps, and rust on the large surface; the coated surface is smooth, uniform in thickness, and free from porosity. (5) Within 3.5 m of length, the error in vertical, horizontal or angle is less than 3mm, and the error in total length is less than 12mm. (6) The error when connecting two consecutive components is less than 1.6mm.