The 840 arch shaped equipment has the characteristics of light weight, large load-bearing capacity, and good performance, and is widely used in the field of multi story and high-rise steel structure buildings. The architectural characteristics of an arched roof are: no beams or sandalwood, a tall and spacious space that can be freely divided and combined, and easy to use. Light weight, strong rigidity, good elasticity, and superior performance. Mechanical bite lock seam, airtight, time-saving and lifting. The design style is reasonable, reserved, capable of withstanding large wind loads and diverse seismic forces, and has strong adaptability. Whether it is a bustling street or a remote town, it is economical, beautiful, and applicable.