ASTM A194 Grade 2H Nuts

ASTM A194 Grade 2H nuts are the industry benchmark for high-strength, internally threaded fasteners, engineered specifically for critical high-pressure and high-temperature service. Governed by the ASTM A194 / ASME SA194 standards, these nuts are essential for securing flanged connections in demanding environments like power plants and petrochemical refineries.

The “2H” denotes the two manufacturing requirements that allow this performance, which is a medium carbon steel (for example, AISI 1045) and a Quench and Temper (Q&T) heat treatment. This treatment, which consists of heating the steel, rapidly quenching it, then tempering it at a minimum heat of 850°F (455°C), produces a fine-grained, tough microstructure that embodies the strength and hardness of the service-finished nut. 

In order to handle these high loads, A194 Gr 2H nuts are typically manufactured in heavy hex pattern. This is a heavy robust nut pattern that is noticeably thicker and wider than a standard nut, creating a bigger bearing surface creating a greater interface of threads to repel stripping under high torque. When discussing a Grade 2H nut performance, the true measure is the Proof Load Strength, which is the maximum tensile load imposed on the nut before it loses any of the contour of the threads. These nuts are engineered so their proof load exceeds the ultimate tensile strength of recommended companion bolts (like the ASTM A193 B7), ensuring a safe and predictable joint where the bolt, not the nut, is the yielding component.

• ASTM A193 Grade B7: This is the most standard and widely used combination for high-temperature, high-pressure flange bolting.
• ASTM A320 Grade L7: For low-temperature service applications.
• ASTM A354 Grade BD: For high-strength structural bolting at ambient temperatures.
• ASTM F1554 Grade 105: High-strength anchor bolts used in structural foundations.

“Contact Jade Special Metals today with your requirement for ASTM A194 GR. 2H Nuts. We assure you of the best quote.

Oil & Gas: Flange connections on pipelines, pressure vessels, valves, and wellheads.
Power Generation: High pressure steam piping, turbine manifold, heat exchangers, and boiler piping systems.
Petrochemical & Refineries: Process equipment, reactors and industrial piping with high-integrity connections.
Heavy Construction & Infrastructure: Structural steel connections and heavy-duty anchor bolting systems

• Expert Manufacturer: As a certified manufacturer, we control the critical heat treatment of our A194 2H Nuts to ensure consistent strength and reliable performance.
• Certified Quality: Every order comes with a Mill Test Certificate (MTC) to assure quality as we comply with the standards for ASTM A194 and have complete traceability.
• Fast Delivery From Stock: Our vast inventory of 2H Heavy Hex Nuts in a full range of sizes ensures rapid dispatch to help you meet your project deadlines.
• Competitive Pricing: By buying direct from the manufacturer, you cut out middlemen and receive a highly competitive price on certified, high-quality nuts.
• Proven Global Exporter: We offer full logistics to ensure your ASTM A194 2H Fasteners are delivered globally, consistently and on-time.