1, determine the ceiling height, and play lines on the surrounding walls. Fix the angle aluminum along the elastic line. According to the specifications of aluminum gusset plate and ceiling area, the dragon skeleton structure and keel position are determined.

2, install the main keel, after the completion of all, unified correction position and height.

3. Install the derrick, do rust prevention work, thoroughly correct the dragon skeleton, and install the aluminum gusset plate. In this way, the ceiling can be closed normally even if there is no wall.