Fasteners dedicated to solar mounting structures are core connectors to guarantee long-term stable operation of PV racking systems. NINGBO TOPBOLT METALWORKS CO., LTD. supplies mainstream fastening hardware for all types of solar projects, widely applied in metal rooftop PV, ground-mount solar farms and solar tracker frameworks.
Introduction of Mainstream PV Fasteners
Hex Bolts & Hex Nuts
Standards: DIN933, DIN934, ASTM A325
Used for connecting aluminum or steel solar mounting rails and brackets, to prevent loosening caused by continuous wind vibration. Hot-dip galvanized versions are suitable for inland solar stations, while stainless steel types are recommended for coastal areas with heavy salt spray.
Self-Drilling Screws
Standard: DIN7504
The most popular rooftop solar fastener. Equipped with drill bit tip, no pre-drilling required. It secures solar clamps directly on metal roof sheets and greatly improves installation efficiency on site.
Flat Washers & Spring Lock Washers
Standards: DIN125, DIN127
Flat washers distribute clamping pressure evenly and protect aluminum profiles from scratches. Spring lock washers provide anti-loosening function against cyclic wind vibration. Usually supplied as matched sets with bolts and nuts.
Fully Threaded Rods / Studs
Standard: DIN975
Designed for ground solar foundation and long-span bracket connections. They can be cut to custom lengths on site, ideal for heavy-duty solar support frames and base anchoring.
Lag Screws
Standard: DIN571
For wooden roof substrates. It delivers excellent pull-out resistance to fix solar brackets on timber beams, widely adopted for residential rooftop PV installations.
Supply Overview
| Item | Details |
| Product Types | Hex Bolts & Nuts, Self-Drilling Screws, Flat & Spring Washers, Threaded Rods, Lag Screws |
| Materials | Carbon Steel, Stainless Steel |
| Surface Finishes | Hot-Dip Galvanizing, Zinc Plating, Passivation |
| Standards | DIN933 / DIN934 / DIN7504 / DIN125 / DIN127 / DIN975 / DIN571, ISO, ANSI/IFI, GB |
| Customization | Custom sizes per drawing, special dimensions, project kitting service |
Related Products
Hex Bolts & Hex Nuts
Self-Drilling Screws
Flat Washers & Spring Lock Washers
Fully Threaded Rods / Studs
Lag Screws
Looking for Fasteners for Your Solar Mounting Project?
TOPBOLT supplies complete fastening solutions for photovoltaic mounting systems. Share your drawings, material requirements, surface finish, applicable standards and order quantity with our team to discuss a suitable solution.
