ASTM A500 Hollow Section Standard

The ASTM A500 hollow section standard defines the specifications for cold-formed welded and seamless carbon steel structural tubing. These hollow sections are widely used in construction, infrastructure, and industrial engineering due to their strength, dimensional accuracy, and versatility. The standard provides clear guidelines for chemical composition, mechanical properties, manufacturing processes, and dimensional tolerances, ensuring safety and reliability in structural applications.

ASTM A500 Standard Overview

ASTM A500 covers four primary grades of carbon steel hollow sections: Grade A, Grade B, Grade C, and Grade D. The standard applies to round, square, and rectangular hollow sections, with thicknesses up to 25 mm and lengths commonly ranging from 6,000 mm to 14,000 mm.
Key features include:
Manufacturing types: Cold-formed welded, seamless, or ERW (electric resistance welded).
Dimensional tolerances: Thickness tolerance ±10% for all sizes.
Surface protection options: Black uncoated, varnish or oil coating, pre-galvanized, or hot-dip galvanized.
End finishes: Beveled, square cut, or end-capped.

Grades and Chemical Composition

The differences among ASTM A500 Grades A, B, C, and D primarily result from variations in carbon content. Lower carbon content improves weldability, while higher carbon content increases strength.
Grade A – Suitable for light structural use, with moderate strength.
Grade B – Offers a balance of strength and weldability, making it the most commonly used grade.
Grade C – Features lower carbon content, providing superior weldability and reduced cracking risk.
Grade D – Designed for thicker wall sections, ensuring high toughness and structural stability.
Other elements such as manganese, phosphorus, sulfur, and copper (when specified) remain consistent across all grades.

Mechanical Properties

Grade	Yield Strength (min, MPa)	Tensile Strength (min, MPa)	Elongation (%)
A	228	310	25
B	317	400	23
C	345	427	21
D	317	400	23

Applications of ASTM A500 Hollow sections

ASTM A500 structural pipe is widely used in the construction of various building structures. Its high strength and durability make it an ideal material for supporting stairways, frames, and floor structures.

Bridge Construction
Bridge structures require extremely high durability and load-bearing capacity, and ASTM A500 structural pipe excels in this regard.
ASTM A500 steel pipe is used in the manufacture of key bridge components such as beams and longitudinal girders. Its high strength ensures reliable operation in a variety of environmental conditions.

Communication Towers and Support Structures
Communication towers and support structures require a strong material that can withstand wind forces and heavy loads. ASTM A500 structural pipe plays a key role in these demanding applications, ensuring that communication equipment is securely supported while meeting stringent requirements for structural strength and stability.