BS 4395 High Strength Hex Structural Bolt Black Oxide Carbon Steel M3 Thread Fastener

Product Description

The BS 4395 High Strength Hex Structural Bolt with Black Oxide Finish is a durable fastening solution designed for machinery assembly, steel structure connections, industrial equipment, automotive components, and general engineering applications. Manufactured from high strength carbon steel, this bolt offers reliable mechanical strength, stable fastening performance, and strong resistance to loosening under demanding working conditions.

This bolt features a hexagonal head, a smooth shank section, and a precision-machined metric thread. The hex head allows easy tightening with standard spanners, sockets, or power tools. The partially threaded design helps provide better shear resistance and improved structural connection performance compared with fully threaded bolts in certain applications.

The Black Oxide Finish gives the bolt a dark black appearance and provides mild corrosion resistance when combined with protective oil. It is commonly used for high strength bolts, machinery fasteners, industrial hardware, and applications where a black surface finish is preferred.

Key Features

• BS 4395 style high strength hex structural bolt
• Made from high strength carbon steel
• Black Oxide Finish for a dark industrial appearance
• Hex head design for easy installation
• Partial thread design for strong structural fastening
• Suitable for machinery, steel structure, equipment, and automotive use
• OEM and ODM customization available
• Available in different sizes, lengths, grades, and packaging options

Product Specifications

Surface Treatment: Black Oxide Finish

The Black Oxide Finish is a common surface treatment for carbon steel and alloy steel fasteners. It creates a black surface layer on the bolt, improving appearance and providing basic anti-rust protection when used with oil or other protective coatings.

Product Advantages

Common Applications

The BS 4395 High Strength Hex Structural Bolt with Black Oxide Finish is widely used in industrial and mechanical fastening systems.

Material and Custom Options

Why Choose Black Oxide Hex Structural Bolts?

Black oxide hex bolts are commonly selected when customers need a dark surface finish, good dimensional accuracy, and reliable fastening performance. Compared with thick coatings such as hot dip galvanizing, black oxide creates a thinner surface layer, which helps maintain better thread accuracy.

For high strength bolts, black oxide is often used together with protective oil to reduce surface oxidation during storage and transportation. It is suitable for indoor machinery, equipment assembly, automotive parts, and general industrial applications.

Quality Control

FAQ

1. What is a Black Oxide Finish?

Black oxide is a chemical surface treatment that forms a black layer on carbon steel or alloy steel fasteners. It improves appearance and provides basic corrosion resistance, especially when combined with protective oil.

2. Is Black Oxide better than zinc plating?

Black oxide provides a dark appearance and better dimensional accuracy because the coating layer is very thin. Zinc plating usually offers better corrosion resistance, while black oxide is more commonly used for high strength and machinery fasteners.

3. Can black oxide bolts be used outdoors?

Black oxide bolts are mainly recommended for indoor or low-corrosion environments. For outdoor, humid, or marine environments, hot dip galvanized, zinc plated, or stainless steel bolts are usually better choices.

4. What material is this bolt made from?

This bolt is made from high strength carbon steel. Alloy steel and stainless steel versions can also be supplied according to customer requirements.

5. Is this bolt fully threaded or partially threaded?

The product shown is a partially threaded hex bolt. Full thread versions can also be customized if required.

6. Can you supply matching nuts and washers?

Yes. We can supply matching hex nuts, heavy hex nuts, flat washers, spring washers, and complete bolt-nut-washer assemblies.

7. Can the size be customized?

Yes. We can customize size, length, thread pitch, material, strength grade, surface treatment, and packaging according to drawings, samples, or customer specifications.

8. What information is needed for a quotation?

Please provide the bolt size, length, thread type, material, grade, surface finish, quantity, packaging requirement, and destination port or delivery address.