Carbon Steel Grade Class 4.8 8.8 10.9 12.9 Metal bolt Square Hammer Head T Bolt

| 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 (also known as square - headed screws) are versatile fasteners utilized in various industrial and construction scenarios. They are characterized by their square - shaped heads, which confer several benefits. Regarding materials, they can be produced from a range of metals, with stainless steel (e.g., 18 - 8 (A2), A4, SUS304, SUS316, SUS316L) being a common selection. This stainless - steel material provides excellent corrosion resistance, making them ideal for applications in harsh environments such as marine or chemical plants. For instance, in coastal areas where saltwater is prevalent, stainless - steel square head bolts can endure the corrosive effects and maintain their integrity over time. The square - head design offers practical advantages: it allows for easy manual tightening or loosening using a wrench or socket. Unlike some round - headed bolts that may slip under torque, the flat surface of the square head provides a stable grip, making installation and maintenance more convenient, especially in situations where power tools may not be readily available or in tight spaces. Square head bolts come in different sizes (e.g., M2, M8, M12, M16) and strength grades (e.g., A2 - 70, A2 - 80, A4 - 70, A4 - 80) to meet specific load - bearing requirements. High - strength fasteners like these are often used in structural applications, such as building frameworks or heavy - machinery assembly, ensuring the stability and safety of the structure.
- 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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