Anchor bolts often don’t get the same fanfare as a steel structure’s more visible aspects, but they are absolutely essential to securing any structure. Anchor bolts serve the very important role of attaching a steel structure to concrete. Without anchor bolts, the rest of a structure could not exist.

Because there are many different types of anchor bolts, it can be a bit tricky to make sure you have the right ones. We’ll break down the key differences between B7 threaded rod, Grade 8 fasteners, and F1554 anchor bolts (grades 55 and 105) to help you make an informed decision for your next project.

Anchor Bolt Types

Choosing the right anchor bolt depends largely on what conditions the bolt will endure and the strength needed for your structure. The most important consideration, however, is the actual application. This dictates all the properties an anchor bolt needs to possess. Here, we’ll go through three of the best anchor bolts for steel: B7 threaded rod, Grade 8 fasteners, and F1554 anchor bolts (grades 55 and 105).

B7 Anchor Bolts: Built for Heat

For high-temperature environments, B7 anchor bolts reign supreme. B7 threaded rod is a chromium molybdenum alloy that derives its strength from its quenching and tempering process at a scorching 1,100° F. Because of its immense strength amid extreme temperatures, B7 threaded rod is ideal for oil and gas, chemical and petroleum applications like pressure vessels, valves, and pipe flanges.

Available in lengths up to 40 feet, B7 threaded rod comes in hot-rolled, heat-treated conditions and can even be turned and polished for a smooth finish.

Grade 8 Anchor Bolts: Maximum Strength in Standard Conditions

Grade 8 fasteners have one of the highest tensile strengths among common steel anchor bolts (150 ksi), which comes through heat treatment. Similar to B7, Grade 8 is quenched and tempered, but at a cooler 800° F. This makes it stronger than Grade 5 and B7 for standard applications. However, it can be slightly more brittle due to the heat-treatment process. Grade 8 fasteners are available in plated finishes up to eight inches and in plain finishes in full lengths.

F1554 Anchor Bolts: The Construction Champion

The F1554 family of anchor bolts has unmatched versatility beyond its strength (which is immense). We call it the construction champion because this family of anchor bolts is specifically designed for construction projects like buildings, bridges, and traffic signals. The two most common grades of F1554 include:

• F1554 Grade 55: a high-strength, low-alloy steel ideal for most construction anchoring needs.
• F1554 Grade 105: an even stronger choice, used when maximum strength is required. Grade 105 is an alloy, heat-treated steel option for critical applications.

Choosing the Right Steel Anchor Bolt

When you’re ready to select an anchor bolt, it’s all about the application. Every type of anchor bolt has its advantages over the others, so the true deciding factor is the application. What are you building and what are the conditions? For projects requiring high heat and pressure, a B7 threaded rod is your best bet. With standard construction projects that need high tensile strength, Grade 8 fasteners are a solid choice. Where specific strength and configuration requirements are involved in certain construction projects, F1554 anchor bolts (grades 55 & 105) have the most versatility.

Capital Steel & Wire stocks all the raw materials you need for making your bolts and fasteners in B7, Grade 8, or F1554. Contact us today to learn about our stocking programs and competitive pricing, or to get a quote for your next project.