Galvanized high-strength bolts for photovoltaic brackets often break automatically after installation due to hydrogen embrittlement. Hydrogen atoms penetrate into metal texture during pickling and electroplating process. This article divides hydrogen risk grades, provides on-site inspection methods, and formulates unified dehydrogenation construction rules for photovoltaic construction teams.
| Bolt Grade | Surface Treatment | Hydrogen Risk | Dehydrogenation Requirement | PV Application Limit |
| 8.8 Grade Carbon Steel | Galvanized | Low Risk | Optional Baking | Secondary Bracket Only |
| 10.9 Grade Alloy | Electro-galvanized | High Risk | Mandatory Double Baking | Main Beam Re-inspection Required |
| 10.9 Grade Alloy | Hot-dip Galvanized | Medium Risk | Factory High-temperature Baking | Outdoor Exposed Position |
| 12.9 Grade Alloy | All Galvanized Process | Extreme Risk | Double Dehydrogenation | Buried Base Position Only |
Hydrogen invades bolt texture during electroplating process, coating damage during construction accelerates embrittlement, improper material selection for coastal power stations increases bolt fracture probability.
Inspect hydrogen content before warehouse entry, bake high-risk bolts at 220℃ for 4 hours, protect bolt coating during installation, conduct special inspection within two months after construction to replace potential defective bolts timely.