UB 1000x400x321 is a Universal Beam designation used to identify a specific hot-rolled steel section. This page provides the verified dimensional and section data listed in the source content, together with a downloadable DWG resource for CAD reference.
The designation is useful for section selection and drawing coordination, but it should not be treated as a complete set of exact dimensions. Use the listed depth, width, web thickness, flange thickness, root radius, sectional area, and unit weight when checking the profile or preparing detailed drawings.
UB 1000x400x321
Universal Beams
refer to : EN 10365:2017
a European standard that defines the dimensions, tolerances, and sectional properties for hot-rolled steel channels, I-beams, and H-beams used in construction and engineering. It ensures uniformity and compatibility across European structural steel products.
Dimension : 990x400x16.5×31
Depth : 990 mm
Width : 400 mm
Web Thickness : 16.5 mm
Flange Thickness : 31 mm
Root Fillet Radius : 30 mm
Sectional Area : 408.8 cm2
Unit Weight : 320.9 kg/m
How to read the section information
The section name is a compact catalog designation. The detailed values below it describe the actual profile geometry and mass per unit length. This distinction matters because a designation may use rounded identifying values rather than reproduce every exact dimension.
- Depth describes the overall distance across the section from one outer flange face to the other.
- Width is the overall flange width.
- Web thickness identifies the thickness of the central vertical element.
- Flange thickness describes the thickness of the horizontal flange elements.
- Root fillet radius defines the curved transition between the web and flange.
- Sectional area represents the total steel area in the cross-section.
- Unit weight is the mass per unit length and is commonly used for quantity and weight calculations.
Why the root radius matters in detailing
A Universal Beam is not formed from perfectly square internal corners. The root fillet occupies space where the web meets each flange. Plates, stiffeners, bolts, weld preparations, and other attached components should therefore be detailed with suitable clearance from this curved region.
The root radius can also affect CAD tracing and fabrication drawings. A simplified sharp-corner profile may be adequate for some schematic uses, but it should not be mistaken for the complete rolled geometry when fit-up or interference is important.
Using the DWG reference
The drawing resource can support profile identification, layout work, drafting templates, and coordination between structural views. Before relying on it for fabrication or construction, confirm the drawing units, scale, layer organization, profile orientation, and dimensional agreement with the verified data on this page.
A section-profile drawing does not by itself establish connection capacity, member capacity, material grade, tolerances, camber, end preparation, or project-specific fabrication requirements. Those items must be obtained from the governing design documents and reviewed by the responsible technical professionals.
Related reference topics
For a broader workflow, compare this page with Universal Beam size references, I-shape terminology, section-property explanations, steel unit-weight concepts, root-radius detailing guidance, and CAD block verification practices. These related topics help distinguish catalog identification from engineering design and fabrication information.
Frequently asked questions
What does UB mean in UB 1000x400x321?
UB means Universal Beam. It describes a hot-rolled, I-shaped steel section with two flanges connected by a web.
Are the designation numbers the exact section dimensions?
Not necessarily. The source lists the exact profile dimension as 990x400x16.5×31, so users should rely on the detailed dimensional fields rather than infer all geometry from the designation alone.
What is the listed unit weight?
The source content gives a unit weight of 320.9 kg/m. For quantity work, total member mass is determined from the applicable member length and unit weight, subject to the project’s calculation and procurement requirements.
Why is the sectional area useful?
Sectional area describes how much steel is present in the cross-section. It is relevant to mass relationships and several engineering calculations, but it is not a complete statement of structural capacity.
Can the DWG be used directly for fabrication?
It should first be checked for units, dimensions, geometry, clearances, and consistency with the project documents. Connection design, tolerances, material requirements, and fabrication instructions require separate verification.
Which standard is referenced on this page?
The source content refers to EN 10365:2017. Users should confirm the governing standard, specification, and project requirements before applying the information to design or fabrication work.
