The bottom frame is connected with screws to the bottom cross beam and the bottom side cross beam, purlin 8*4 square pipes x9 are connected with screws
Each column is fixed with six sets of hexagon socket bolts, and the column screws do not need to be tightened
The top frame is connected to the top beam and the top side beam with screws, and the drain hole faces outward.
Install three horizontal square pipes and fix them at the welding angle of the top short beam.