Flange Bolts: Flange Bolts for Piping, Automotive, and Construction: Types & Sizes Available
Section 1 Introduction
In the realm of engineering, construction, and manufacturing, secure and dependable fastening solutions are critical to the structural integrity and functionality of countless applications. Among the various types of fasteners available, flange bolts stand out for their unique design, which offers exceptional holding power and load distribution. This article will delve into the world of flange bolts, exploring their types, applications, benefits, and installation best practices. We will also highlight Welleshaft, a trusted global supplier and contract manufacturer, as a reliable source for high-quality flange bolts.
Section 2 What are Flange Bolts?
Flange bolts are specialized fasteners characterized by a circular flange or washer-like head that is integral to the bolt. This flange is designed to distribute the clamping load over a larger area, eliminating the need for a separate washer in many applications. This design provides increased bearing surface, improving the joint’s stability and reducing the risk of loosening, especially under vibration or heavy loads. Flange bolts are typically used in applications where secure and reliable fastening is crucial, offering a robust alternative to traditional bolts and separate washers.
Section 3 Types of Flange Bolts
The versatility of flange bolts is evident in the wide range of types available, each designed for specific applications and load requirements. Here’s an overview of some of the most common types:
3.1 Hex Flange Bolts: These are the most common type of flange bolt, featuring a hexagonal head with an integrated flange. The hex head allows for easy tightening with standard tools.
3.2 Integral Flange Bolts: These bolts have a flange that is integrally formed as part of the bolt, providing a very strong and secure joint.
3.3 Connecting Flange Bolts: Designed specifically for connecting flanges in piping systems and other applications, ensuring a secure seal.
3.4 Flange Joint Bolts: These bolts are used in flange joint connections, providing a secure and leak-free seal.
3.5 Hexagonal Flange Bolt: A general term for bolts that have a hexagonal head with an integrated flange.
3.6 Bolts for Flanges: This is a broader term encompassing all types of bolts intended for flange connections.
3.7 Flange Connection Bolts: Refers specifically to bolts used in connecting flange systems.
Flange Mounting Bolts: These are specifically for mounting flanges to other components.
3.8 Bolts for Pipe Flanges: Designed to withstand high pressures and temperatures when used in connecting pipe flanges.
3.9 Flange Attachment Bolts: Used to attach a flange to a base or another flange, designed for strength and stability.
3.10 High-Strength Flange Bolts: Manufactured from high-strength materials for applications that require high tensile strength and shear resistance.
3.12 Heavy Duty Flange Bolts: Designed to withstand significant loads and demanding conditions, often found in industrial and construction applications.
3.13 Industrial Flange Bolts: A general term for flange bolts used across a broad range of industrial applications.
3.14 Flanged Head Bolt: Any bolt that has a head with an integrated flange.
3.15 Washer Faced Bolt: Bolts that have a smooth flat bearing surface under the head, sometimes a built-in washer.
3.16 Built-In Washer Bolt: Bolts designed with an integrated washer, which serves to distribute pressure and prevent damage to the surface.
3.17 Bearing Surface Bolt: Bolts with a designed bearing surface to provide even pressure distribution on the mating surface.
3.18 Serrated Flange Bolts: Feature serrations or ridges on the underside of the flange to enhance grip and prevent loosening, particularly in high-vibration environments.
3.19 Captive Washer Bolts: These bolts have a washer that is mechanically held in place, preventing it from being lost or forgotten during assembly.
3.20 Shoulder Bolt with Flange: Features a smooth cylindrical shoulder section under the head, providing precise alignment and pivot functionality, with added flange for load distribution.
3.21 Structural Flange Bolt: Specifically designed for use in structural applications, known for their high strength and reliability.
3.22 Pre-Assembled Washer Bolt: Bolts with a washer already assembled for faster and more efficient installation.
Section 4 Flange Bolts – A Comparative Overview
| Bolt Type | Material Compatibility | Load Capacity | Application | Key Feature |
| Hex Flange Bolt | Steel, Stainless Steel, Alloy | Medium-Heavy | General purpose, Automotive, Industrial | Easy tightening, wide use |
| Integral Flange Bolt | Steel, Stainless Steel, Alloy | Medium-Heavy | General purpose, Automotive, Industrial | One piece design, high strength |
| Connecting Flange Bolt | Steel, Stainless Steel, Alloy | Medium-Heavy | Piping systems, structural connections | Secure connection, precise alignment |
| Flange Joint Bolt | Steel, Stainless Steel, Alloy | Medium-Heavy | Pipe flange connections, sealing | Leak-free seal, robust |
| Hexagonal Flange Bolt | Steel, Stainless Steel, Alloy | Medium-Heavy | General purpose | Reliable fastening |
| Bolts for Flanges | Steel, Stainless Steel, Alloy | Medium-Heavy | Various flange applications | Versatile |
| Flange Connection Bolts | Steel, Stainless Steel, Alloy | Medium-Heavy | Flange systems | Secure connections |
| Flange Mounting Bolts | Steel, Stainless Steel, Alloy | Medium-Heavy | Mounting flanges | Stability |
| Bolts for Pipe Flanges | Steel, Stainless Steel, Alloy | Medium-Heavy | Pipe flange connections | High pressure and temperature resistance |
| Flange Attachment Bolts | Steel, Stainless Steel, Alloy | Medium-Heavy | Attaching flanges | Strong and reliable attachment |
| High Strength Flange Bolt | Steel, Alloy | Heavy | High load applications | High tensile strength |
| Heavy Duty Flange Bolt | Steel, Alloy | Heavy | Industrial and construction applications | Durability in demanding conditions |
| Industrial Flange Bolt | Steel, Stainless Steel, Alloy | Medium-Heavy | Broad industrial applications | Versatility and reliability |
| Flanged Head Bolt | Steel, Stainless Steel, Alloy | Medium-Heavy | General use | Head with built in flange |
| Washer Faced Bolt | Steel, Stainless Steel, Alloy | Medium | General Use | Smooth bearing surface |
| Built-In Washer Bolt | Steel, Stainless Steel, Alloy | Medium | General Use | Pressure distribution, damage prevention |
| Bearing Surface Bolt | Steel, Stainless Steel, Alloy | Medium | General Use | Even pressure distribution on mating surface |
| Serrated Flange Bolt | Steel, Stainless Steel, Alloy | Medium | High vibration environment | Enhanced grip, prevents loosening |
| Captive Washer Bolt | Steel, Stainless Steel, Alloy | Medium | Various assemblies | Prevents washer loss |
| Shoulder Bolt with Flange | Steel, Stainless Steel, Alloy | Medium | Precise alignment and pivot | Shoulder alignment and load distribution |
| Structural Flange Bolt | Steel, Alloy | Heavy | Structural applications | High reliability and strength |
| Pre-Assembled Washer Bolt | Steel, Stainless Steel, Alloy | Medium | Various assembly | Faster and easier installation |
Note: Load capacities are relative and vary based on size, material, and installation quality.
Section 5 Benefits of Using Flange Bolts
5.1 Superior Load Distribution: The integrated flange distributes the clamping force over a larger area, preventing damage to the mating surface and minimizing the risk of loosening.
5.2 Reduced Assembly Time: By eliminating the need for separate washers, flange bolts can streamline the assembly process, reducing installation time and costs.
5.3 Improved Joint Stability: The increased bearing surface provides a more stable connection, particularly in dynamic environments with vibration or cyclic loading.
5.4 Enhanced Security: Flange bolts offer a more secure fastening solution than traditional bolts with separate washers, ensuring a reliable and durable connection.
5.5 Corrosion Resistance: Flange bolts are available in various materials, including stainless steel and alloy steel, to offer excellent resistance to corrosion and environmental factors.
5.6 Versatile Applications: The different types and sizes of flange bolts make them adaptable to a broad range of industries and applications.
Section 6 Common Applications of Flange Bolts
The wide range of applications for flange bolts includes:
6.1 Automotive Industry: Securing components in engines, chassis, and transmissions.
6.2 Construction: Joining structural elements, installing handrails, and securing machinery.
6.3 Manufacturing: Assembling equipment, securing piping systems, and attaching fixtures.
6.4 Aerospace: Fastening critical components in aircraft and spacecraft.
6.5 Marine: Securing equipment and structures exposed to harsh marine environments.
6.6 Piping and Plumbing: Connecting flanges in piping systems, ensuring a secure and leak-free seal.
6.7 Industrial Equipment: Fastening machinery, pumps, and various heavy-duty components.
Section 7 Flange Bolt Sizes and Dimensions
Flange bolts come in a wide range of sizes and dimensions, measured by diameter, length, thread pitch, and head size. Here’s an overview of common measurement system used:
Metric System (ISO Standard):
| Bolt Size (mm) | Typical Thread Pitch (mm) | Wrench Size (mm) | Common Applications |
| M6 | 1.0 | 10 | Small machinery, automotive |
| M8 | 1.25 | 13 | Small industrial equipment, automotive |
| M10 | 1.5 | 17 | General machinery, medium duty piping |
| M12 | 1.75 | 19 | Large machinery, structural steel |
| M16 | 2.0 | 24 | Heavy machinery, large structural joints |
| M20 | 2.5 | 30 | High load construction, heavy piping |
| M24 | 3.0 | 36 | Very large structures, industrial applications |
Imperial System (SAE Standard):
| Bolt Size (inch) | Threads Per Inch (TPI) | Wrench Size (inch) | Common Applications |
| 1/4″ | 20 | 7/16 | Light duty assembly |
| 5/16″ | 18 | 1/2 | Small structural applications |
| 3/8″ | 16 | 9/16 | General machinery |
| 1/2″ | 13 | 3/4 | Medium duty construction, automotive |
| 5/8″ | 11 | 15/16 | Structural joints |
| 3/4″ | 10 | 1-1/8 | Heavy duty piping |
| 1″ | 8 | 1-1/2 | High load connections |
Important Note: These tables are indicative, and exact sizes and dimensions will vary depending on the specific standard used (e.g., ASME B18.2.1, DIN 6914, ISO 4017) and the specific manufacturer. It is always critical to verify the technical specifications and to work with reputable suppliers to ensure proper fit.
Section 8 Table of Information on Flange Bolts
| Feature | Description | Benefits | Considerations |
| Flange Design | Built-in washer-like flange under the bolt head. | Increased load distribution, no need for separate washers. | May not be suitable for all applications. |
| Bolt Head Types | Hex, round, pan, and others are available. | Each head type provides unique benefits related to application and design. | Ensure the correct head type is chosen for the available tooling and application. |
| Materials | Carbon steel, alloy steel, stainless steel, and others. | Wide range of applications for material selection, based on corrosion and strength requirements. | Select material appropriate for environmental conditions and structural demands. |
| Size Range | Wide range of diameters and lengths are available in metric (mm) and imperial (inches). | Allows for diverse projects and connection requirements. | Ensure you select the correct diameter and length to meet project requirements. |
| Serrated Flange | Teeth or serrations under the flange. | Improved resistance to loosening in high vibration applications. | May leave minor marks on softer materials, so consider this before selecting. |
| Applications | Automotive, construction, manufacturing, piping, aerospace, and renewable energy applications. | Versatile and adaptable to many industries and uses. | Not suitable for every application, must consider the loads and environments. |
Section 9 Key Considerations When Choosing Flange Bolts
Selecting the right flange bolts is crucial for ensuring the safety and efficiency of any system:
9.1 Material: Consider the environment in which the bolts will be used. Carbon steel bolts are cost-effective for general use, while stainless steel bolts offer superior corrosion resistance.
9.2 Size and Dimensions: Ensure that the bolt diameter, length, and thread pitch are compatible with the flanged components being joined.
9.3 Strength Grade: Select bolts with a strength grade that can withstand the expected loads and stresses.
9.4 Head Type: Choose a head type that is appropriate for the available access space and the required wrenching torque.
9.5 Application Specific Requirements: Consider any specific needs such as high temperature resistance, anti-vibration features, or specific coatings.
Section 10 Flange Bolt Standards
Several standards govern the manufacturing, testing, and performance of flange bolts:
10.1 ISO (International Organization for Standardization): ISO standards ensure global compatibility and quality.
10.2 DIN (Deutsches Institut für Normung): Commonly used in Europe, DIN standards provide specific requirements for bolts.
10.3 ANSI/ASME (American National Standards Institute/American Society of Mechanical Engineers): Widely used in North America, these standards specify bolt dimensions and material requirements.
10.4 SAE (Society of Automotive Engineers): Often used in the automotive sector for their performance characteristics.
Understanding and adhering to these standards are paramount to ensure safety and performance of critical connections.
Section 11 Choose Welleshaft for High-Quality Flange Bolts
Welleshaft stands out as a trusted global supplier and contract manufacturer for flange bolts for several compelling reasons:
11.1 High-Quality Products: Welleshaft’s flange bolts are manufactured using premium-grade materials and advanced production techniques, ensuring superior performance and reliability.
11.2 Extensive Selection: They offer a comprehensive range of flange bolts in various materials, sizes, and types to meet the diverse needs of customers across various industries.
11.3 Customized Solutions: Welleshaft provides contract manufacturing services, enabling customers to obtain custom-designed flange bolts tailored to their unique requirements.
11.4 Global Presence: With a robust global network, Welleshaft ensures timely delivery of products worldwide and maintains a reputation for excellence in the fastener industry.
11.5 Technical Expertise: Their team of experienced engineers and technicians can provide technical guidance and support to help customers select the ideal flange bolts for their specific applications.
11.6 Competitive Pricing: Welleshaft offers competitive pricing without compromising on the quality and reliability of their products, making them a cost-effective partner.
Conclusion
Flange bolts are essential components in various applications where secure and reliable fastening is paramount. Their unique design, with an integral flange, offers improved load distribution, reduced assembly time, and enhanced joint stability. Understanding the different types of flange bolts, their applications, and proper installation techniques will enable you to achieve optimal results and ensure the safety and longevity of your projects. Partnering with a reliable supplier like Welleshaft guarantees that you’ll receive high-quality flange bolts that meet or exceed industry standards. When it comes to secure fastening solutions, trust the precision and reliability of flange bolts.
