Associated Fastening Products is ISO 9001:2008 certified and proud to offer large diameter bolts for a variety of industries and applications. Our advanced hot forging capabilities can hot head bolts based on customer specifications with fast turnaround times. Parts are available in sizes from 1/2″ to 2 1/2″ or 16MM to 50MM diameters, and tight tolerances are held throughout, depending on the process.
There are various types of large diameter bolts that are suitable for many applications.
ASTM A325 Structural Bolts
These are the international standard for heavy hex structural bolts. They are available in different grades, with differing mechanical and chemical characteristics for particular applications. At Associated Fastening Products, our structural bolts are designed, manufactured, and tested to comply with the standards set by ASTM A325, including chemical composition, yield strength, elongation, tensile strength, and rotational capacity of the bolt.
ASTM A325 structural bolts have shorter thread lengths than standard hex bolts, and the heavy hex head accommodates a large load-bearing area for added strength, making them suitable for structural connections.
A193 Grade B7 Heavy Hex
A193 Grade B7 heavy hex bolts are frequently used in high pressure, high-temperature applications involving steel pipe flanges and flanged fittings. When required, they are mated with A194 Grade 2H heavy structural hex nuts. These high strength hex bolts have a heavy pattern head which increases the bearing surface, allowing the clamping load to be distributed over a large area.
Hot Headed Bolts
Hot headed bolts generally range from 3/8″ diameter to 2″ diameter and are manufactured from a variety of materials, including stainless steel. Hot headed bolts are made by heating a round bar in a furnace, then forming the head of the bolt in a header or die. Hot heading offers better formability of certain head styles at a lower cost. Forging produces a much stronger component than a cast or machined part, allowing hot headed bolts to be used in applications where reliability and safety are critical.
Applications & Industries
Large diameter bolts are used across various industries for many applications, including:
- OEM. The OEM market has a demand for large diameter bolts to supply to other companies to use as components for their products.
- Automotive. The failure of a critical fastener, such as large diameter bolts, can be catastrophic in automotive applications. A single failure can destroy an engine or vehicle, costing thousands of dollars and putting the driver, passengers, and bystanders at risk of serious injury. With the proper selection and installation of the right fastener, failure can be virtually eliminated.
- Transportation. Fasteners used in the transportation industry, such as applications for railroads, tractor-trailers, and over-the-road vehicles, endure long hours and extensive wear and tear, making large diameter bolts ideal for use.
Why Choose Large Diameter Bolts from Associated Fastening
At Associated Fastening Products, we feature short lead times and offer pre-expedited and hot rush ordering. We handle long and short-run productions, special packaging, stocking, Kanban, and Just-in-Time programs. For more information about our large diameter bolt services or our other products and services, please see the table below or contact us today.