This page provides a concise dimensional, sectional-property, and CAD reference for the Hybox 355 CHS 323.9×6. It is intended for drafters, designers, engineers, students, and other technical users working with circular hollow sections.
The source information identifies the section by its diameter and wall thickness and includes its sectional area and unit weight. The accompanying DWG can support drawing coordination and section identification, while the stated reference standard provides context for dimensional tolerances and sectional properties.
Hybox 355 CHS 323.9×6
Hybox 355 Circular Hollow Sections
refer to : EN 10219-2:2006-04
the European standard that specifies tolerances, dimensions, and sectional properties for cold-formed welded structural hollow sections made of non-alloy and fine grain steels. It complements EN 10219-1, which covers technical delivery conditions.
Diameter : 323.9 mm
Thickness : 6 mm
Sectional Area : 59.9 cm2
Unit Weight : 47 kg/m
Section reference summary
- Section: Hybox 355 CHS 323.9×6
- Shape family: Circular hollow section
- Diameter: 323.9 mm
- Thickness: 6 mm
- Sectional area: 59.9 cm²
- Unit weight: 47 kg/m
- Referenced dimensional standard: EN 10219-2:2006-04
How to interpret the CHS designation
CHS means circular hollow section. The section designation combines the stated circular diameter with the wall thickness, making it useful for schedules, drawing labels, material lists, and model coordination. Because similar designations can differ by only one component, both values should be checked when matching a section to a drawing or specification.
What the listed properties describe
The sectional area represents the steel area in the cross-section. It is a geometric property used in structural calculations and quantity-related work, but it is not a load capacity by itself.
The unit weight expresses the section mass per unit length. It can support material takeoffs and preliminary weight summaries when used with the required member lengths. Fabrication items such as plates, weld metal, bolts, fittings, coatings, and allowances are separate from the bare section weight.
Standards context
The cited EN 10219-2 reference addresses tolerances, dimensions, and sectional properties for the relevant cold-formed welded structural hollow-section category. Its companion part addresses technical delivery conditions. A section reference page should therefore be read alongside the governing project specification, product documentation, and applicable standard requirements.
Using the DWG in a detailing workflow
The provided CAD resource can help with section identification, drafting, and coordination. After insertion, check drawing units, scale, layer organization, linework, and section labeling. Confirm that the CAD geometry corresponds to the stated diameter and thickness before using it in shop details, connection layouts, or fabrication documents.
A section outline alone does not establish connection capacity, member strength, material compliance, or suitability for a particular project. Final design and detailing decisions should be verified against the project requirements and reviewed by the responsible qualified professional.
Related reference topics
Useful related SteelSTD.com topics include circular hollow-section dimensions, hollow-section property concepts, section weight and unit-weight interpretation, welded and bolted connection detailing, base-plate concepts, and CAD drawing workflows. Comparing those topics can help distinguish geometric reference data from design resistance and fabrication requirements.
Frequently asked questions
What does CHS mean?
CHS stands for circular hollow section, a closed steel section with a circular profile and a defined wall thickness.
What does 323.9×6 identify?
On this page, the designation corresponds to the stated diameter of 323.9 mm and thickness of 6 mm. Both components should be retained in schedules and drawing callouts to avoid confusion with other CHS sizes.
Is sectional area the same as load capacity?
No. Sectional area is a geometric property. Structural resistance also depends on material properties, member length, stability, loading, connection behavior, applicable design rules, and other project conditions.
How is the listed unit weight used?
The unit weight of 47 kg/m can be paired with member length for section-weight takeoffs. Additional connection and fabrication items should be accounted for separately.
Can the DWG be used directly for fabrication?
The file can assist drafting and coordination, but its units, scale, geometry, layers, and labels should be checked before use. Fabrication documents also require project-specific connection details, tolerances, materials, and professional verification.
