China Wholesale Automotive Fasteners Manufacturers and Automotive Fasteners Factory

ANSI/ASME B18.2.1 automotive hexagonal flange bolts are designed with a hexagonal head and an integral flange to increase the bearing surface, reduce the compressive stress between the bolt and the connected parts, and improve the stability of the connection. The size range is from 1/4 inch to 6 inches. ANSI/ASME B18.2.1 automotive hexagonal flange bolts are widely used in the automotive industry, especially in the fastening connection of engines, chassis and structural components to ensure high-strength and high-reliability assembly requirements.

The bolts are usually made of high-strength alloy steel and heat-treated to meet the automotive industry's strict requirements for mechanical properties, fatigue resistance and corrosion resistance. In addition, its threads comply with the unified thread standards (UNC/UNF), and can provide surface treatments such as galvanizing, electroplating or Dacromet according to different use environments to enhance corrosion resistance and extend service life.

ANSI/ASME B18.2.1 automotive hexagonal bolts comply with the American National Standards Institute (ANSI) and the American Society of Mechanical Engineers (ASME) B18.2.1 standard. The bolts are designed with a standard hexagonal head, have excellent mechanical properties and reliable locking capabilities, and are used in the automotive manufacturing field, including the fastening of engines, chassis systems and structural parts to ensure the safety and stability of vehicle assembly.

The bolts are made of high-strength alloy steel and undergo a rigorous heat treatment process to improve tensile strength and fatigue life to meet the automotive industry's requirements for high-load and high-vibration conditions. In addition, its threads comply with the unified thread standard (UNC/UNF), and can provide surface treatments such as galvanizing, electroplating or Dacromet according to different usage environments to enhance corrosion resistance and extend service life.

GB21 small hexagon head bolts are standard fasteners used in automobile manufacturing, mechanical equipment, building structures and other fields. The bolts comply with the GB21 national standard and have excellent mechanical properties and reliable connection strength. Its small hexagon head design can provide higher torque transmission in a limited space while optimizing installation efficiency.

GB21 small hexagon head bolts are made of high-strength alloy steel and undergo a heat treatment process to improve wear resistance and tensile strength to meet the high requirements of the automotive industry for fasteners. The surface treatment of the bolts can be galvanized, electrophoresed or other anti-corrosion processes as required to enhance rust resistance and improve durability. In the automotive field, GB21 small hexagon head bolts are often used in key parts such as engine components, chassis connections, suspension systems, etc., providing vehicles with safe and reliable fastening solutions

GB5785 Fine Pitch Hexagon Head Bolts are precision-engineered fasteners featuring a hexagonal head and fine thread pitch, optimized for applications requiring high clamping force, vibration resistance, and dimensional accuracy. The fine pitch design (e.g., smaller thread spacing compared to standard coarse threads) allows for finer adjustments and improved load distribution, making these bolts ideal for assemblies subjected to dynamic stresses. Their geometry adheres to strict tolerance standards, ensuring compatibility with threaded holes in high-precision components.

In the automotive sector, GB5785 bolts are extensively employed in critical systems such as engine mounts, gearbox housings, and chassis components. The fine threads enhance fatigue resistance under cyclic loads, a common challenge in vehicle operation, while the hex head design enables secure tool engagement for controlled torque application. This is vital in automotive manufacturing, where consistent fastener performance directly impacts safety and longevity.

ANSI/ASME B18.2.1 Square Head Bolts are standardized fasteners distinguished by their square-shaped heads, designed for applications requiring robust torque transmission and secure mechanical engagement. The square head geometry provides a larger contact surface for wrench or spanner tools, enabling higher torque application with reduced risk of rounding compared to hexagonal heads. These bolts typically feature coarse or fine threads, depending on the specification, and are manufactured to meet ANSI/ASME B18.2.1 dimensional and mechanical requirements, ensuring interchangeability and reliability in industrial settings.

Square Head Bolts are often utilized in legacy or specialized vehicle systems where their design aligns with historical engineering practices. For example, they may be found in vintage vehicle restorations, heavy-duty truck chassis assemblies, or certain suspension components where the square head's resistance to slippage under high torque is advantageous. While less common in modern automotive mass production due to the prevalence of hexagonal heads for automated assembly, they remain relevant in niche scenarios requiring manual maintenance or compatibility with older designs.

ANSI/ASME B18.5 Round Head Square Neck Bolts combining a smooth, rounded head with a square neck to prevent rotation during installation. This unique design ensures secure seating in square-shaped recesses or mating components, eliminating slippage even under extreme torque. Manufactured to ANSI/ASME B18.5 standards, these bolts deliver consistent dimensions and mechanical properties, making them ideal for assemblies requiring both aesthetic smoothness and anti-rotational stability.

In automotive engineering, ANSI/ASME B18.5 bolts are commonly used in components exposed to high vibration and torsional stress. Their square neck feature is particularly advantageous in drivetrain systems, axle housings, and heavy-duty suspension linkages, where rotational resistance is critical to maintaining structural integrity. The rounded head design also reduces protrusion risks, making them suitable for automotive applications requiring streamlined profiles, such as underbody panels or transmission mounts

Passenger Car Wheel Boltss are used to securely attach the wheel to the vehicle's hub assembly. Bolts withstand dynamic loads, vibrations and harsh driving conditions, ensuring the structural integrity of the wheel-to-axle connection. In the automotive industry, wheel hub bolts are manufactured from high-strength materials such as carbon steel or alloy steel, are subjected to strict tolerance control, and are often equipped with anti-corrosion coatings such as zinc plating for enhanced durability. Their precise thread design and torque specifications are essential to maintain wheel alignment and prevent accidents caused by stress loosening.

Automotive wheel bolts meet international standards such as ISO 10101 or DIN 74361 to ensure their reliability. These parts are vehicle-specific, with thread pitch, length and seat type (such as tapered, spherical or flat seat) customized to original factory requirements. Our automotive wheel hub bolts combine precision engineering with strict quality control to ensure optimal load distribution and long-term performance. Whether used for replacement or upgrade, these bolts are certified and tested for tensile strength and fatigue.

The GB4231 U-Bolt is a standardized fastener compliant with China's national specifications, engineered to secure cylindrical or tubular components in demanding environments. Widely used in automotive systems, such as heavy-duty truck chassis and commercial vehicle suspension systems, its U-shaped design ensures robust clamping force to withstand vibrations, shocks, and dynamic loads. Constructed from carbon steel or alloy steel, it undergoes surface treatments like zinc plating or Dacromet coating to resist corrosion and abrasion, making it ideal for harsh conditions like salt spray or humidity.

The GB4231 U-Bolt features calibrated threading and a radius-optimized U-bend, minimizing stress concentration and metal fatigue—critical for automotive parts exposed to constant motion. In commercial vehicles, it is integral to fixing rear axle leaf springs, directly impacting load-bearing safety and stability. Standardized dimensions ensure compatibility with OEM components, while customizable options (diameter, length, coating) address specialized automotive aftermarket needs.

The 7-Shaped Anchor Bolt, characterized by its angular bend resembling the numeral "7," is a heavy-duty fastener designed to embed securely into concrete or masonry. Widely utilized in automotive facilities, it anchors machinery, assembly line equipment, and structural supports to withstand high static and dynamic loads. Crafted from high-grade carbon steel or alloy steel, it undergoes hot-dip galvanizing or epoxy coating to resist corrosion, ensuring longevity in industrial environments such as automotive workshops or testing labs.

This bolt’s unique geometry optimizes pull-out resistance, with the bent section acting as a mechanical lock within the base material. Threaded ends allow adjustable tensioning, critical for aligning automotive manufacturing equipment or securing vibration-prone systems. Compliance with standards like ISO 1461 or ASTM F1554 ensures reliability, while customizable lengths and diameters cater to specific automotive infrastructure projects, from floor-mounted robotics to overhead conveyor installations.

The ANSI/ASME B18.16.4 Automotive Hexagon Flange Nut is a robust fastening solution engineered to meet the rigorous demands of automotive applications. Designed with a wide flange base, it distributes clamping force evenly across mating surfaces, minimizing the risk of loosening under vibration—a critical feature in dynamic automotive environments. Its hexagonal shape ensures compatibility with standard tools, streamlining assembly and maintenance processes, while the precision-machined threads guarantee secure, backlash-free engagement with bolts. Ideal for high-stress components like chassis systems, suspension assemblies, and brake calipers, this nut combines high tensile strength with corrosion-resistant finishes (such as zinc plating or Dacromet coating) to withstand harsh road conditions and temperature fluctuations. Automotive engineers rely on its reliability for critical connections in transmissions, exhaust systems, and wheel hubs, where consistent performance directly impacts safety and durability. By adhering to strict ANSI/ASME dimensional and material standards, the B18.16.4 ensures seamless integration with existing designs, reducing downtime and enhancing operational efficiency. For manufacturers seeking a trusted, cost-effective fastener that balances strength, precision, and longevity, this hex flange nut stands as a cornerstone of automotive assembly excellence.

The GB6177.2 Fine Pitch Hexagonal Flange Nut is a precision-engineered fastener tailored for the demanding requirements of automotive systems, combining reliability with advanced design. Featuring a fine-pitch thread profile, it delivers enhanced clamping precision and resistance to loosening in high-vibration environments, making it ideal for critical automotive components such as engine mounts, transmission systems, and steering assemblies. The integrated flange base distributes load evenly, reducing stress concentration on mating surfaces while eliminating the need for separate washers—streamlining assembly and lowering production costs. Manufactured to China’s GB standards, this nut ensures strict dimensional accuracy and material consistency, with options for electro-galvanized or phosphate coatings to combat corrosion from road salts, moisture, and temperature extremes. Its hexagonal head allows seamless integration with standard tools, accelerating maintenance workflows without compromising torque performance. Engineers trust GB6177.2 for applications requiring micrometer-level adjustments, such as brake line fittings or sensor mounts, where precision directly impacts vehicle safety and efficiency. By balancing high tensile strength, anti-fatigue properties, and cost-effectiveness, this fine-pitch flange nut empowers automotive manufacturers to achieve robust, long-lasting assemblies while adhering to rigorous quality benchmarks. For projects demanding accuracy, durability, and compliance with domestic standards, GB6177.2 is the definitive choice for modern automotive engineering.

The ANSI/ASME B18.16.6 American All-Metal Torque Type Automotive Hexagon Lock Nut is a premium fastening solution designed to excel in high-stakes automotive environments where reliability is non-negotiable. Engineered with an innovative all-metal torque-locking mechanism, it eliminates the risk of loosening caused by vibration or thermal cycling, making it indispensable for critical applications like chassis joints, suspension linkages, and drivetrain assemblies. The hexagonal body ensures compatibility with standard tools, enabling swift installation and maintenance, while the precision-formed threads maintain consistent clamp load even under extreme dynamic stresses. Constructed from high-grade alloy steel with a durable protective coating—such as zinc or manganese phosphate—it resists corrosion from road chemicals and moisture, extending service life in harsh under-vehicle conditions. Automotive engineers specify this nut for torque-sensitive systems, including brake caliper mounts and steering knuckles, where micrometer-level preload accuracy directly impacts safety and performance. By meeting stringent ANSI/ASME dimensional and mechanical standards, it guarantees seamless integration with existing designs, reducing assembly errors and downtime. For manufacturers prioritizing fail-safe joints without compromising on weight or space, the B18.16.6 delivers unmatched tensile strength, reusability, and compliance, solidifying its role as the go-to locking fastener for next-generation automotive innovation.