Structural Nuts in Grade A563 Steel

Heavy Hex Nuts for Structural Applications

Structural A563 Heavy Hex Finish Nuts, also known as A563 Heavy Hex Nuts, Heavy hex finish nuts, and structural heavy hex nuts, are used for many fastening applications. Heavy hex finish nuts are often used with bolts when a heavier, stronger and thicker nut is needed, often for strength or a thicker finished look. Structural nuts such as these can help increase the load capacity of the bolt fastened to it.

The hexagonal shape makes these nuts easy to grasp with a wrench or pliers. They are installed on the opposite side of the materials being fastened. With the bolt head or machine screw head on the other side, they compress the materials together for a secure fit.

Structural A563 Heavy Hex Nuts are thick, strong heavy duty nuts typically used to create structures through steel to steel structural connections. They are often applied alongside structural bolts and washers to metal beams and girders. Compatible with A325 and A490 Structural Bolts.

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A563 Heavy Hex Nut Specifications

Nut Sizes	Flats	Thickness
1/2"-13	0.875"	0.504"
5/8"-11	1.062"	0.631"
3/4"-10	1.250"	0.758"
7/8"-9	1.438"	0.885"
1"-8	1.625"	1.012"
1-1/4"-7	2.000"	1.251"

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FAQs

What is a heavy hex nut?

Heavy hex nuts are larger and thicker versions of standard hex nuts. They are often used to complement larger, heavier, and high strength bolts to improve the connection's strength further.

What is a563?

A563 is an ASTM specification of steel covering the chemical and mechanical requirements for eight grades of carbon and alloy steel nuts for general structural and mechanical uses on bolts, studs, and other externally threaded parts.

Is ASTM a563 weldable?

Structural nuts gain strength through the heat-treating process and are not typically welded. As a general principle, welding should not be done on structural nuts and bolts.

How do you size a hex nut?

Hex nuts are sized by the diameter of the internally threaded hole and the thread pitch of the hole's threading. For example, a 1/4"-20 hex nut has a 1/4 inch diameter hole with 20 threads per inch of internal threading. When selecting a nut to match a bolt, be sure they have the same diameter and thread pitch.

What are hex nuts?

Hex nuts are hexagonal blocks of material, typically metal, with a hole punched through that is threaded. Hex nuts, or hex finish nuts, are the most common type of finish nut used. The hexagonal shape makes these nuts easy to grasp with a wrench or pliers. These nuts are often used with screws and bolts when mechanically joining materials together.

What is a hex nut used for?

Hex nuts are used alongside machine threaded fasteners to complete a secure assembly. The head of the screw or bolt clamps down on the material while the nut clamps down on the opposite side. This effectively "sandwiches" the assembly securely together.

How does a hex nut work?

Hex nuts work jointly with machine threaded fasteners such as bolts, anchors, and machine screws to effectively clamp down on both sides of the fastened material. The bolt and nut threading causes friction against each other, allowing a secure fit for general applications. A lock nut is used instead if the application would be subject to high amounts of vibration.