High Strength Grade Class 4.8 8.8 Carbon Steel Metal bolt Square Head Bolt Zinc plated
| Name | Metal Bolt |
| Standard | DIN, ASME, ANSI, ISO |
| Material | carbon steel |
| Place of Origin | China |
| Finish | Polish, Passivation, Black, Galvanization, Chromate, Dacromet |
| Certificate | ISO9001:2008, ROHS |
| Used | Building Industry Machinery |
| Thread Type | Coarse, Fine |
| Usage | Fastening |
| Function | Connection, Fastening and Decoration |
| Strength | High |
| Size | Various sizes available |
| Measurement System | INCH, Metric system |
Square head bolts (square head screws) are essential fasteners across industries. Their defining feature is the square - shaped head, which delivers practical advantages. Material - wise, they can be fabricated from diverse metals; stainless steel variants (such as 18 - 8 (A2), A4, SUS304, SUS316, SUS316L) are highly favored for their superior corrosion resistance, enabling use in harsh settings like marine or chemical facilities. In coastal regions with high saltwater exposure, these bolts withstand corrosion and retain structural integrity. The square - head geometry enables straightforward manual tightening/loosening via wrenches or sockets. Unlike round - headed bolts that may slip under torque, the flat square - head surface ensures a stable grip, simplifying installation and maintenance—especially in confined spaces or when power tools are inaccessible. Available in sizes like M2, M8, M12, M16 and strength ratings (e.g., A2 - 70, A2 - 80, A4 - 70, A4 - 80), they meet specific load demands. High - strength square head bolts are frequently employed in structural applications (e.g., buildingames, heavy fr- machinery assembly) to guarantee structural stability and safety.
- Industrial Machinery Assembly: Used to connect heavy-duty components (e.g., gearboxes, engine blocks) in manufacturing equipment, ensuring stable load distribution during operation.
- Construction Engineering: Secures structural elements like steel beams, columns, and prefabricated panels in buildings, bridges, and infrastructure projects.
- Automotive & Aerospace: Joins critical parts (e.g., chassis frames, engine mounts, aircraft fuselage sections) where high strength and vibration resistance are required.
- Power Generation Equipment: Fixes turbine components, generator casings, and transmission systems in thermal, hydro, or wind power plants.
- Heavy-Duty Furniture & Fixtures: Assembles robust furniture (e.g., industrial workbenches, storage racks) and fixtures (e.g., machine tool bases) needing durable, long-term connections.
| Aluminum | Excellent thermal/electrical conductivity but naturally soft. May produce gelatinous buildup during processing. |
| Titanium | EDM machining recommended. Requires deionized water to control heat during processing. |
| Steel | Very strong metal. Wire cutting machines often preferred for complex features. Requires heat management. |
| Brass | High tensile strength, easy to machine but requires slow cutting speed due to softness. |
- Medium carbon steel construction: Offers balanced strength (typically 4.8–12.9 grade) and toughness, suitable for moderate to high-load applications.
- Reusable & cost-effective: Can be removed and reinstalled multiple times without significant loss of performance, reducing long-term maintenance costs.
- Gasket-free compatibility: Directly interfaces with mating surfaces or nuts, eliminating the need for additional gaskets while maintaining sealing integrity.
- High-strength bolt compatibility: Works seamlessly with Class 8.8 and 10.9 high-strength bolts, enhancing overall joint reliability under dynamic or static loads.
- Durable wholeness: Manufactured with precision threading and surface treatments (e.g., zinc plating, black oxide) for corrosion resistance and extended service life.
A: We are factory and OEM are available.
A: Generally 7-10 days if in stock, or 15-20 days if not in stock (depending on quantity).
A: Yes, we offer free samples but customer pays freight cost.
A: 30% T/T in advance, balance before shipment or L/C.
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