The Douglas fir used is native to North America and is transported domestically through local processing of logs into laminar sheets, which takes about 30 days to transport. After the materials arrive at the domestic port, it takes about 10 days to clear customs, and the transportation cycle of materials takes about 40 days in total.

1. Secondary drying→ 2. Material classification→ 3. Materials preferred → 4. Comb finger connection → 5. Finger-in-Growth Health→ 6. Planed on all sides→ 7. Dosing Gluing→ 8. Planking and pressing → 9. Material sent for inspection→ 10. Glued wood planing→ 11. Surface sanding → 12. Arc beam robotic arm machining→ 13. Paint Sanding→ 14. Spray paint→ 15. Protective packing

Testing of main mechanical parameters: glulam strength testing, material drawing and shearing testing, and lamellar bending resistance testing. When new products and new processes are used, targeted product research and development, experimental testing, new project promotion and application, etc. will be carried out. Only after successful demonstration will the new materials and new processes be promoted in a large scale to provide good R&D guarantee services.

Permissible deviations for the production of timber trusses, timber beams (including purlins) and timber columns shall be in accordance with Table 4.3.1.