Metric Serrated Flange Bolts

In the demanding environment of industrial production, the problem of fastener loosening and failure in high-vibration scenarios has long plagued many companies. Under continuous vibration, ordinary fasteners are prone to loosening, which can lead to equipment downtime and maintenance, affecting production efficiency, or even causing safety accidents, resulting in significant economic losses and casualties. This is especially true in the automotive, machinery, and steel structure industries, which have extremely high requirements for the anti-loosening and anti-vibration performance of fasteners.

We are a source factory with over 20 years of experience in fastener research, development, and manufacturing, deeply rooted in the industry for many years, and have a profound understanding of the core needs of fasteners in various fields.

Core Technological Advantages

1. Integrated Serrated Flange Design for Ultimate Anti-Loosening and Anti-Vibration

The Metric Serrated Flange Bolts head features an integrally formed flange with precisely rolled serrations on the edge. The core advantage of this unique design lies in its anti-loosening performance. When tightened, the serrations firmly "grip" the surface of the connected part, generating significant frictional resistance, fundamentally preventing the bolt from loosening due to vibration. The anti-vibration effect far surpasses that of ordinary fasteners.

It eliminates the need for additional spring washers or locking washers, achieving reliable anti-loosening, significantly simplifying the company's BOM (Bill of Materials) management, reducing parts procurement and inventory costs, while shortening the installation process, improving assembly efficiency, and lowering labor costs.

The flange surface significantly increases the bearing area between the Metric Serrated Flange Bolts and the workpiece, distributing the preload evenly across the workpiece surface, effectively preventing the bolt head from embedding into the connected part, avoiding material damage caused by stress concentration, protecting the integrity of the workpiece surface, and improving the overall stability of the connection.

2. High-Quality Materials and Precision Craftsmanship, Building a Solid Foundation of Strength

Material selection is precisely matched to different needs: high-quality alloy steels such as 40Cr and 35CrMo are used to ensure the core strength of the bolts, suitable for high-load scenarios; high-quality carbon steel is used for its excellent cost-effectiveness, meeting general mechanical connection needs. Each batch of raw materials undergoes rigorous screening, controlling quality from the source. Utilizing advanced cold heading forming technology, the Metric Serrated Flange Bolts head and flange are formed in a single process, resulting in continuous metal flow lines and a dense internal structure, with strength far exceeding that of machined products.  Combined with precision thread rolling technology, the processed metric standard threads achieve a 6g accuracy level, with full thread profiles and smooth mating, eliminating the risk of thread damage and ensuring convenient assembly and reliable connection.

3. Multi-specification and multi-grade coverage, adapting to all application scenarios

Complete strength grades: Covering 8.8, 10.9, and 12.9 high-strength grades. 8.8 grade offers good overall mechanical properties, suitable for general mechanical connections; 10.9 grade is high-strength, widely used in automobile manufacturing, engine components, and heavy machinery; 12.9 grade is ultra-high-strength, known as "special-grade bolts," with extremely high tensile strength, suitable for extreme scenarios such as aerospace, racing cars, and high-load precision equipment.

Diverse surface treatments: Offering various surface treatments including black oxide, electro-galvanizing, hot-dip galvanizing, and Dacromet. Black oxide treatment is economical and practical with a clean appearance; electro-galvanizing offers superior rust prevention and complies with RoHS environmental standards; hot-dip galvanizing provides a thick coating for super corrosion resistance, suitable for harsh environments such as outdoor applications, bridges, and power towers; Dacromet eliminates the risk of hydrogen embrittlement and offers extremely high corrosion resistance, suitable for high-end automobiles and military applications.

Core Technical Parameters

Typical Application Scenarios

With years of industry service experience, our metric serrated flange bolts have been widely used in many demanding fields, becoming a trusted choice for numerous customers:

1. Automotive and Transportation Industry: Suitable for securing core components such as engine cylinder heads, wheel hubs, chassis suspension systems, and gearbox parts. Strength grades 10.9 and 12.9 are preferred, effectively resisting high-frequency vibrations during vehicle operation and ensuring driving safety.

2. Mechanical Equipment Manufacturing: Used in engineering machinery, agricultural machinery, pump and valve connections, motor end covers, etc.  Excellent anti-loosening and anti-vibration performance ensures stable connections during continuous operation, reducing maintenance downtime.

3. Steel Structure Construction: Suitable for steel structure node connections, curtain wall fittings, power and communication towers, and other outdoor or heavy-load applications. Combined with anti-corrosion treatments such as hot-dip galvanizing, it can withstand harsh environmental corrosion and ensure the long-term stability of building structures.

4. Industrial Automation: Used for connecting precision parts such as robot joints and automated production line frames. High-precision manufacturing processes ensure accurate assembly, and anti-loosening performance guarantees continuous and stable operation of the equipment.

Company Strength and Quality Assurance

We understand that fasteners, though small, carry great responsibility, and we always prioritize product quality. As a source factory located in China's fastener capital, we possess 20 advanced cold heading machines and comprehensive testing equipment, building a mature R&D, production, and sales system. We can independently control all aspects of production to ensure stable product quality.

We have established a strict full-process quality control system: spectral analysis is performed on raw materials before warehousing to accurately control chemical composition; all key indicators such as bolt hardness and tensile strength are fully inspected during the production process; and multiple tests, including salt spray tests and torque tests, are conducted before finished products leave the factory to prevent unqualified products from entering the market. The company fully implements ISO 9001 quality management system certification, and our products are CE certified, meeting international export standards. Each batch of products has a unique quality assurance certificate (MTC), traceable to the raw material furnace number and heat treatment batch, giving customers peace of mind. Our product range is extensive, including not only Metric Serrated Flange Bolts but also heavy-duty hex bolts, heavy-duty hex nuts, threaded rods, studs, washers, and more.  Materials include carbon steel, alloy steel, and stainless steel, all strictly adhering to international standards such as DIN, ISO, EN, JIS, ASTM/ANSI/ASME/SAE, BS, and AS. Our products are exported to North America, Europe, Australia, Southeast Asia, the Middle East, Latin America, and other regions, comprehensively meeting the diverse procurement needs of customers in various industries.

Reasons to Choose Us

1. Direct supply from the source factory, outstanding cost-effectiveness: As a direct manufacturer, we eliminate intermediaries, providing customers with highly competitive factory prices. We also have large warehousing facilities, ensuring ample stock of standard products for quick delivery.

2. Fast response capability, guaranteed delivery: We provide free samples for customer testing and verification. Small batch orders are delivered quickly within 3-5 days, and large batch orders have a 99% on-time delivery rate, precisely matching customers' production schedules.

3. Professional technical support, worry-free cooperation: Our team of engineers has extensive industry experience and can provide customers with professional selection advice. We also offer failure analysis services for fastener failures, helping customers solve challenging connection problems.