The main load-bearing primary beam for factory buildings, engineered with exceptionally high flexural strength, stands as the preferred structural solution for large-span roofing applications across various types of industrial facilities. These primary beams are specifically designed to carry the most significant loads within the structural system, including dead loads from roofing materials, insulation, decking, and mechanical equipment, as well as live loads such as snow, maintenance traffic, and dynamic forces from overhead cranes. The beams are fabricated from high-strength structural steel sections, often wide-flange beams (W-beams), plate girders, or customized built-up sections, optimized through advanced engineering analysis to achieve maximum spanning capacity with minimal material usage. Their robust design provides superior resistance to bending, shear, and lateral-torsional buckling, ensuring safety and stability. Advanced welding and fabrication techniques ensure consisten…