American Standard ASTMA354 mentions nut grade DH, what does it mean? The nut grade DH mentioned in A354 means that the mechanical properties and chemical composition meet his requirements, just like the hexagonal nuts in other A563 standards and A194 standards, all of which meet its chemical composition requirements and mechanical performance requirements. It is a qualified product. a563 is only a nut grade standard, not a size standard, it is impossible to have a size. And there are dozens of grades of a563.
The ASTMA563 specification covers the requirements for carbon and alloy steel nuts. ASTMA563 grade nuts contain carbon and the more carbon added, the harder it will become after heat treatment. But the A563 nut also becomes less ductile, which means it loses strength and less plasticity when deformed. Whether heat treated or not, the higher the carbon content of the A563Dh nut, the worse the weldability of the metal, and the higher the carbon content, the lower the melting point. ASTM A563 Grade A square nuts are designed for use with square head bolts, they are often replaced by cheaper hex nuts or square pressed nuts. It is used with square bolts or generally with polar wire hardware.
ASTMA563 grade heavy hex nuts are thicker and heavier. Its parts are larger in diameter.
A larger wrench and socket are also required for installation. Compared to standard hex nuts, the load strength is higher and it can carry more weight very easily. ASTM A563 Grade C lock nut is a nut that resists vibration and torque loosening. There are many types of lock nuts, but they can be broadly divided into those that use friction to stop loosening, and those that have some form of the positive locking mechanism. ASTM A563 grade DH cap nuts are used to protect the underlying bolt threads, but also provide a clean appearance and may improve the safety of certain joints and applications. When the application requires a finish or all rough edge fasteners and exposed threads must be covered, nuts provide an excellent solution for this situation. The A563 Hex is a six-sided universal fastener with female threads. It is one of the most common nuts and it is used with anchors, bolts, screws, studs, threaded rods, and any other fasteners with machine threads.
DT is known for producing heavy-duty hex nuts. We have a full range of heat treatment machines in-house for improving the hardness and mechanical properties of heavy hex nuts to meet different demanding fields. The standards we list below are most ASTM A194/A563 and ANSI/ASME B18.2.2 heavy duty hex nuts. Compared to finished hex nuts, heavy duty hex nuts are of a higher grade, with a slightly wider and thicker diameter to accommodate longer thread engagement lengths and better resistance to stretching or widening.