Round Head Square Neck Bolts

Hebei Dongshao Fastener Manufacturing Co., Ltd. is a well-known supplier and manufacturer of round head square neck bolts in China.

Featured Product

The Round head Square Neck bolts produced by the company is round and can be easily passed through the round hole, making installation and disassembly easier. Its neck has a square shape, hence its name. This design increases its contact area with the nut, thereby increasing the stability of torque transmission.

1. Structural and Design Advantages

Smooth Round Head Design: The bolt head features a smooth, rounded profile that allows for seamless insertion into pre-drilled circular holes. This design not only enhances the efficiency of equipment installation and disassembly but also ensures an aesthetically pleasing appearance and improved safety.

Unique Square Neck Structure: The distinctive square neck design locks securely into the mating slot, providing a self-locking function during tightening that prevents the bolt from rotating. This design significantly increases the contact area with the base material or washer, thereby greatly enhancing the stability of torque transmission.

2. Material and Manufacturing Characteristics

Premium High-Performance Materials: Our core products are manufactured using high-quality raw materials such as stainless steel and alloy steel. These materials offer excellent tensile and yield strength, ensuring the bolts resist deformation or fracture even in complex, high-load operating environments.

Advanced Surface Treatment (Dacromet Technology): The bolt surfaces can be treated with advanced Dacromet anti-corrosion coating technology. This process imparts superior weather resistance and exceptional oxidation and rust protection, effectively blocking environmental corrosion and exponentially extending the product's service life.

3. Wide Range of Applications

Dongshao’s round head square neck bolts play a critical role in fastening components across various heavy machinery, transportation vehicles, and infrastructure projects:

Automotive and Transportation: Widely used for fastening wheels, axles, and body frames in automotive manufacturing.

Engineering and Agricultural Machinery: Utilized for securing structural components in construction machinery, lifting equipment, and modern agricultural machinery.

Industry and Construction: Suitable for industrial applications requiring high seismic resistance and anti-loosening capabilities, such as photovoltaic mounting systems and steel structures.

Product Parameter

Manufacturing Capabilities & Global Service

Production Equipment & Technical Support

Dongshao Fasteners has established a comprehensive, end-to-end manufacturing facility. We are equipped with advanced cold-heading machinery and dozens of specialized hot-forging units, and have invested in high-speed nut-forming machines from Taiwan. Complemented by CNC and conventional lathes, pneumatic and hydraulic presses, thread-rolling machines, milling/grinding/drilling equipment, and dedicated heat-treatment lines, the company is capable of both standardized mass production and the custom manufacturing of irregular or non-standard parts based on customer drawings.

Core Product Portfolio

In addition to round-head square-neck bolts, our product line covers a wide range of categories:

High-Strength Construction Series: Large hex bolts and tension-control (TC) bolts for steel structures; high-strength hex nuts and bolts (e.g., ANSI/ASME A325 and A490 series).

New Energy & Specialized Power: Hot-dip galvanized bolts for photovoltaic systems and specialized bolts for wind power applications.

Fully Threaded Rods & Anchoring Series: ANSI/ASME B7 threaded rods; chemical and mechanical anchors; GB expansion anchors; fully threaded double-end studs.

Stainless Steel & Accessories: Stainless steel combination screws; bolts and sleeves for embedded mounting brackets; ANSI/ASME F436 flat washers and A563 nuts.

Full-Lifecycle Service System

Pre-sales Technical Support: Gaining a deep understanding of customer needs to provide professional technical consultation, material selection advice, and one-stop customized solutions.

In-process Management: Rigorous control of order processing and end-to-end logistics tracking to ensure safe and timely product delivery.

Post-sales Support: Comprehensive technical guidance, maintenance support, and customer training to ensure the long-term performance and value of the fastening systems during operation.