ASTM A500 Gr C structural tube is a cold-formed carbon steel structural tube conforming to the American Society for Testing and Materials (ASTM) standard A500. "Gr C" indicates quality grade C, and it is suitable for general structural applications.
ASTM A500 Gr C Cold Formed Rectangular Hollow Section Chemical Composition
| ASTM A500 | C, max | Mn, max | P, max | S, max | Cu, min |
| Grade C | 0.23 | 1.35 | 0.035 | 0.035 | 0.20 |
ASTM A500 Gr C Cold Formed Structural Rectangular Hollow Section Mechanical Properties
| ASTM A500 | Tensile strength, min | Yield strength, min, | Elongation in 2 in. (50.8 mm) min, % |
| Grade C | 427 MPa, 62 000 psi | 345 MPa, 50 000 psi | 21 |
Dimensional tolerance system:
The outer diameter tolerance adopts the ASTM A500 GRC's unique "plus-over" system: +0.4/-0.8 mm deviation is allowed for side lengths ≤ 50 mm; +0.6/-1.2 mm for the 50-100 mm range; and the tolerance for > 100 mm extends to +1.0/-1.6 mm. Wall thickness tolerance follows the "under-tolerance" principle, stipulating that the smallest wall thickness must not be less than 87.5% of the nominal value. The perpendicularity deviation of rectangular tubes is strictly required, with the diagonal difference controlled within 1.5% of the side length. It is worth noting that ASTM A500 GRC allows for slight torsion up to 0.5°, but the straightness deviation per meter must not exceed 1.6 mm.
A500 GRC (American standard) square tubing is commonly used in steel structure frames, curtain wall supports, and roof trusses. Its square cross-section design facilitates connection with other components while effectively distributing loads. For example, in high-rise buildings, square tubing can serve as columns or beams, bearing vertical and horizontal forces. The hollow structure of the square tubing reduces overall weight, lowering transportation and installation costs. In machinery manufacturing, A500 GRC square tubing is used for equipment supports, conveyor tracks, and guardrails; its high-precision dimensions ensure ease of assembly.
A500 GRC Square tube factory
