What Are the Installation Requirements for Embedded Countersunk Bolts? Anchoring Technology and Qinglong Group's Precision Construction Standards

The installation quality of embedded anchor bolts in GRC components directly affects the connection safety of the curtain wall system, and four strict requirements must be enforced: "precise positioning, adequate depth, verticality control, and anti-rust treatment." The Qinglong Group enterprise standard stipulates: anchor center position deviation ≤±2mm, embedding depth ≥40mm (or 10 times the bolt diameter), verticality deviation ≤1°, and exposed threads coated with epoxy zinc-rich paint for protection. In the roofing project of the Hainan International Convention and Exhibition Center, we used laser-positioned molds (precision ±0.5mm) and torque-controlled electric drills (accuracy ±5%), achieving a first-time pass rate of 99.95% for 120,000 embedded anchor bolts, laying the foundation for the roofing system to withstand ten years of typhoon tests. Embedded anchor bolts are the "root" of the curtain wall—not the slightest deviation can be tolerated.

Positioning Accuracy Is the Prerequisite for Safety

CNC-machined positioning molds ensure anchor group position deviation ≤±1mm. For shaped panels, 3D scanning setting-out is used, with BIM models guiding installation. Qinglong Group provides custom positioning frames for each panel type, greatly improving efficiency while ensuring precision.

Embedding Quality Is the Key to Load-Bearing

Drilling depth = design depth +10mm (to accommodate dust), with hole diameter 2-4mm larger than the bolt diameter. Holes are cleaned using the "three blows, two brushes" process to ensure clean hole walls. Anchoring adhesive is injected to 2/3 of the hole depth, and the anchor is slowly screwed in to the design depth. We conduct on-site spot checks of pull-out force, requiring ≥20kN.

Verticality Control Affects Mechanical Performance

Digital angle gauges are used to control verticality; any deviation >2° requires reinstallation. For group anchor installation, full-length steel straightedges verify overall flatness. Our installation toolkits include special verticality correctors.

Anti-Rust Treatment Ensures Long-Term Durability

Exposed threads and washers must be coated with epoxy zinc-rich paint (dry film thickness ≥60μm) or fitted with plastic protective caps. For coastal projects, 316 stainless steel is the preferred anchor material. Any rust found during regular inspections is treated immediately.

Embedded anchor bolts may be small, but they are a major safety matter. Qinglong Group ensures every connection point is reliable and durable through standardized construction and rigorous inspection.