Description

ASTM A193 B7 Hex Bolt

ASTM A193 B7 Hex Bolt – Specifications & Properties

ASTM A193 B7 hex bolts are strong and reliable, making them ideal for medium-high temperature applications. Manufacturers use heat-treated Chromium Molybdenum steel, allowing these bolts to handle temperatures up to 450°C (840°F). Because of this, industries that need high strength and durability frequently choose them.

How B7 Bolts Are Made

Manufacturers create ASTM A193 Grade B7 bolts and threaded studs from chromium-molybdenum steel. To improve strength and toughness, they quench and temper the steel, making the bolts more durable. As a result, Grade B7 is the most commonly used type in construction and industrial applications.

B7 vs. B16 – What’s the Difference?

The main difference between B7 and B16 lies in their chemical makeup. B16 contains vanadium, which helps it handle higher temperatures than B7. Because of this, industries working in extreme heat often prefer B16 over B7.

For most applications, engineers pair ASTM A194 Grade 4 Heavy Hex Nuts with B16 studs and bolts. However, Grade 7 nuts are also commonly used.

Key Properties of These Bolts

• ASTM A193 B7 bolts work well in medium-high temperature environments.
• L7 bolts have the same chemical and physical properties as B7 but quenching and tempering at 800°F increases their strength.
• Grade 8 bolts contain 0.28-0.55% carbon, 0.030% max phosphorus, and 0.050% max sulfur, ensuring high durability.
• L7 bolts undergo Charpy V Notch tests at -101°C (-150°F) to make sure they perform well in cold temperatures.

Final Thoughts

In summary, ASTM A193 B7 provide excellent strength and heat resistance, making them a top choice for many industries. However, B16 bolts work better in extremely high temperatures. By knowing the differences, engineers can pick the right bolts for their projects.