Grades of ASTM A500 Steel Structural Tubing

ASTM A500 is a standard specification set by ASTM International for cold-formed welded and seamless carbon steel tubing used in structural applications. This standard outlines the requirements for tubes that are used in bridges, buildings, and other structures that require welding, bolting, or riveting. It includes a wide range of tubing shapes such as round, square, rectangular, and special shapes made from carbon steel. Known for its strength and durability, ASTM A500 steel structural tubing is a staple in many construction and engineering projects.ASTM A500 is cold-formed welded seamless carbon steel structural tubing intended for welded, riveted or bolted bridge and building structures and general structural purposes.

ASTM A500 steel tubing refers to carbon steel tubes produced for structural applications. These tubes are typically cold-formed and can be welded or seamless. The tubes are classified based on their chemical composition, tensile strength, and heat treatment. The common applications include structural support in buildings, bridges, and mechanical systems, where high strength and durability are paramount.

ASTM A500 is divided into four grades, each offering different mechanical properties and tailored to various application needs:

Grade A: This grade is the most basic and is designed for general structural applications. It features a minimum yield strength of 39,000 psi and a minimum tensile strength of 45,000 psi, with elongation determined by the wall thickness.

Grade B: This is the most widely used grade of ASTM A500 tubing. It has a higher yield strength of 46,000 psi and a tensile strength of 58,000 psi, making it suitable for most structural uses. The elongation is determined by the wall thickness.

Grade C: This grade provides even higher strength than Grade B, with a minimum yield strength of 50,000 psi and a tensile strength of 62,000 psi, making it ideal for heavy-duty applications. Elongation is also determined by wall thickness.

Grade D: The highest strength grade, Grade D must undergo heat treatment, providing enhanced toughness and strength. This grade is used in more specialized applications where maximum strength is required.

Composition, %

ASTM A500 Carbon Steel Mechanical Properties

Tensile strength refers to the amount of stretching stress a material can withstand before breaking or failing. The ultimate tensile strength of A500 carbon steel is calculated by dividing the area of the steel by the stress placed on it, which is expressed in terms of pounds or tons per square inch of material. Tensile strength is an important measure of A500’s ability to perform in an application.

Tensile Requirements

Round Structural Tubing:

Shaped Structural Tubing:

Due to its strength and versatility, ASTM A500 structural pipe is used in a variety of applications across multiple industries:

Building Frames: ASTM A500 is commonly used in the construction of building frames and columns, particularly in multi-story buildings and bridges.

Highway and Roadway Signposts: The tubing’s excellent torsional resistance and ease of construction make it ideal for use in highway signs and traffic posts.

Communication Towers: The structural tubing’s durability is also a key factor in the construction of communication towers, where the material must withstand environmental stress.

Oil and Gas Industry: Grade C and Grade D ASTM A500 pipe are used extensively in oil field services, where they must resist extreme conditions and provide strong, reliable support.

The different grades of ASTM A500 structural pipe—Grade A, Grade B, Grade C, and Grade D—offer a wide range of strength levels to suit various applications. From general structural use with Grade A to high-strength demands with Grade D, ASTM A500 provides versatile solutions for the construction and infrastructure industries. Whether you are working on a simple structural frame, a bridge, or a communication tower, ASTM A500 tubing offers the strength, durability, and flexibility needed to meet the most demanding engineering standards.