Overview
ASTM A500/A500M-23 covers cold-formed welded and seamless carbon-steel structural tubing in round, square, rectangular and special shapes. A complete HSS order identifies grade, route, section dimensions, wall, length, finish, tests and any project-specific notch-toughness or fabrication requirements.
Designation and acceptance
A500 is a structural tubing product specification, not a generic name for every hollow steel section. Grade and unit system control the property basis; shape, outside dimensions, wall and corner geometry define the ordered section. Welded and seamless routes are permitted, but the specification does not automatically qualify dynamically loaded welded details for low-temperature toughness.
Members and selection
| Designation | Selection context |
|---|---|
| Grade B | Common structural branch; verify section and design-standard property basis. |
| Grade C | Higher-strength branch frequently selected for HSS construction; do not substitute without recalculation. |
| Grade D | Heat-treated branch requiring condition and availability confirmation. |
| Round / square / rectangular / special | Order the exact geometry, outside dimensions, wall, corner and length tolerances. |
Comparison framework
| Criterion | Decision context |
|---|---|
| A500 vs A513 | A500 supplies structural property acceptance; A513 is mechanical tubing organized around type, processing and finish. |
| Welded vs seamless | Both can conform, but route, weld location and downstream fabrication remain purchasing facts. |
| Grade B vs C | Strength basis differs and affects design, availability and substitution approval. |
| Static vs fatigue/toughness duty | Baseline A500 does not by itself establish project fatigue category or low-temperature notch toughness. |
Performance
- Acceptance under ASTM A500 Structural Tubing depends on the ordered product branch, delivered condition, geometry and specified test basis rather than the standard number alone.
- Actual wall, corner geometry, seam position and local cold forming affect section behavior and fabrication.
- Service suitability remains an engineering decision: catalog section labels do not replace grade, design properties, connection design or project toughness requirements.
Orderable product scope
- Cold-formed round structural tubing in ordered OD and wall.
- Square and rectangular hollow structural sections with defined corners.
- Special-shape structural tubing subject to drawing and mill agreement.
Processing
- Control coping, drilling and welding so local wall damage and residual stress are managed.
- Qualify galvanizing or painting with venting, drainage and coating-compatible details.
- Preserve heat and bundle identity through cutting and fabrication when project traceability requires it.
Applications
- Building and bridge hollow structural members.
- General structural frames, columns, trusses and supports.
- Fabricated equipment frames only when structural acceptance matches the design basis.
Selection
- Confirm that ASTM A500 Structural Tubing covers the required product form and manufacturing or coating route before comparing quotations.
- Select the grade, alloy, temper, coating or delivered condition from service, fabrication and the required acceptance evidence; never infer it from a trade name.
- Require a written technical comparison and responsible-engineer approval before substituting another standard, product route or condition.
Procurement
- State ASTM A500/A500M-23, unit system, grade and welded or seamless route.
- State shape, outside dimensions, specified wall, length, quantity, tolerances and end condition.
- Define surface, weld-seam orientation if critical, straightness/twist and any notch-toughness or supplementary tests.
- Require mill test report, heat/bundle traceability, marking and moisture-protected shipment.