12 Point Flange Bolt

Product Description

12-point flange bolts, also known as ferry bolts, are high-performance fasteners characterized by a 12-point (double-hex) head and an integrated flange. They are the preferred choice for critical, high-torque applications where safety and space-efficiency are paramount.

Mechanical Advantages

• Superior Torque: The 12-point design provides double the contact points of a standard hex bolt. This allows you to apply significantly higher torque with a smaller wrench size, reducing the risk of "rounding off" the head.

• Compact Clearance: Because the 12-point head is smaller than a standard hex head of the same thread size, these bolts are ideal for tight spaces where a socket or wrench has limited room to maneuver.

• High Tensile Strength: These bolts are almost exclusively manufactured in high-strength alloys (like Grade 9 or aerospace-grade stainless) to handle the extreme clamping forces they are designed for.

Common Use Cases

• Performance Automotive: Widely used for cylinder heads, intake manifolds, and drivetrain components.

• Aerospace & Defense: Preferred for jet engines and structural airframe components due to their vibration resistance and strength-to-weight ratio.

• Oil & Gas: Used in high-pressure valves and flanges where a reliable, leak-proof seal is required under extreme stress.

Material & Grade Options

• Alloy Steel (Grade 9 / 170,000+ PSI): These offer the highest strength but require a coating (like black oxide or zinc) to prevent rust.

• Stainless Steel (304 or 316): Used for high-torque applications in corrosive environments, such as marine engines or chemical pumps.

• Exotic Alloys (Inconel / A286): Specialized for extreme heat environments like exhaust manifolds or turbine housings.

Recommended 12-Point Options

ARP High-Strength 12-Point Bolt SetA premium 8740 chrome moly steel bolt set. These are heat-treated to 180,000 psi tensile strength, making them far stronger than standard Grade 8 bolts for automotive and racing use.

304 Stainless 12-Point Flange BoltFor applications requiring both high torque and corrosion resistance. These are ideal for show-quality automotive engines or high-end marine hardware where appearance and durability are equally important.

Zinc Plated 12-Point Ferry BoltA robust industrial option for heavy machinery. The zinc plating provides a layer of protection against moisture while maintaining the high-torque capability of the 12-point head.

Installation Note

To install these, you will need a 12-point socket or box-end wrench. A standard 6-point hex socket will not fit. Ensure you use the correct wrench size to fully engage all 12 points and achieve the intended torque.

Are you looking for these for a structural engine repair or a marine application? Knowing the thread size (e.g., 3/8-16 or M10) can help me find the exact torque specifications for you.