Flange Bolts: Types, Application & More
Flange bolts are specialized fasteners with an integrated washer-like flange that distributes the load and improves stability.
They are widely used in automotive, industrial, and structural applications due to their strength and vibration resistance.
This guide explains their types, sizes, and key applications.
What is a flanged bolt?
A flange bolt is a fastener with a built-in circular flange under the head, eliminating the need for a separate washer.
This design enhances grip, distributes pressure evenly, and prevents loosening due to vibrations.
Flange bolting is commonly used in piping systems, heavy machinery, and automotive assemblies.
Types of Flange Bolts
| Category | Type | Description |
| Classification by Material | Stainless Steel (SS) Flange Bolts | Corrosion-resistant and ideal for marine, chemical, and outdoor applications. |
| Carbon Steel Flange Bolts | Strong and cost-effective but require protective coatings. | |
| Alloy Steel Flange Bolts | High-strength bolts are used in heavy-duty applications. | |
| Classification by Grade | Grade 8 Flange Bolts | High-tensile strength, used in critical load-bearing applications. |
| Grade 5 Flange Bolts | Medium-strength bolts are commonly used in automotive and structural applications. | |
| Classification by Head Type | Hex Flange Head Bolt | Features a hexagonal head with an integrated flange for better load distribution. |
| Serrated Flange Bolt | Has serrations under the flange to prevent loosening. | |
| Classification by Flange Bolting Pattern | Varies by bolt arrangement | Common patterns include circular, rectangular, and staggered designs, depending on the application. |
Application of Flange Bolts: Where Are They Used?
Flange bolts are used in industries where vibration resistance and secure fastening are essential.
Key applications include:
- Automotive Industry – Used in engine assemblies, exhaust systems, and chassis components.
- Piping Systems – Secure pipe connections in oil, gas, and chemical industries.
- Heavy Machinery – Provides stability in industrial equipment and construction machinery.
- Structural Applications – Used in bridges, buildings, and metal frameworks.
More FAQs About Flange Bolts
- What is a flanged bolt used for?
- A flanged bolt is used to provide a secure connection without needing a separate washer, ensuring even load distribution and preventing loosening.
- What is the standard flange bolt size?
- Flange bolt sizes vary, but common sizes range from M6 to M20 in metric and ¼” to ¾” in imperial measurements.
- Are Grade 8 flange bolts stronger than Grade 5?
- Yes, Grade 8 flange bolts have higher tensile strength and are used in critical applications requiring extra durability.
- What is the difference between a hex flange head bolt and a regular hex bolt?
- A hex flange head bolt has an integrated washer-like flange for better load distribution, while a regular hex bolt requires a separate washer.
- How do I choose the right flange bolting pattern?
- The flange bolting pattern depends on the load, pressure, and application. Check industry standards or manufacturer guidelines for the correct configuration.
Flange Bolts: Conclusion
Flange bolts are essential fasteners designed for strength, stability, and vibration resistance in various industries.
Their integrated flange distributes pressure evenly, reducing the need for separate washers.
Understanding their types, sizes, and applications helps in selecting the right bolt for any project.
Choosing high-quality flange bolts ensures durability, safety, and reliable performance.
For more bolt types, check the CNRL product catalog right now!
Resources
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