# T sections

T-shaped stock: equal tees, split structural tees and welded profiles, dimensional identity, centroid and fabrication limits.

Reviewed: 2026-11-01

Tags: materials, stock-forms, structural-sections, tees

## Identify the section family and route

For an ideal sharp-corner tee with **100 × 10 mm flange**, **100 mm overall depth** and **10 mm stem thickness**, the area-weighted centroid is **28.684 mm from the flange face** and **71.316 mm from the stem tip**. Keep the two extreme-fiber distances separate when using section moduli.

A T section has a flange joined to a stem. The shape alone does not establish material grade, manufacturing route or load capacity. Retain the exact section designation, dimensional drawing, alloy/grade and supplied condition.

Montanstahl distinguishes equal stainless T-bars from structural tees obtained by splitting an IPE, HEA or HEB beam longitudinally through its web. Its equal T-bars are produced primarily by laser welding, with dimensional provisions related to EN 10055. A laser-welded tee and a split beam are different product descriptions even when their external envelopes look similar. [Montanstahl equal T-bars and structural-tee distinction](https://www.montanstahl.com/products/stainless-steel-structurals-bright-bars/stainless-steel-tees/equal-t-bars/)

For US terminology, AISC's **February 2012** materials article identifies **WT, MT and ST** as tees split from W, M and S shapes respectively. This naming explanation is retained as historical source context; its older preferred-material recommendations are not adopted here as current purchasing requirements. [AISC, structural tees](https://www.aisc.org/globalassets/modern-steel/steelwise/022012_steelwise_spec.pdf)

Do not shorten a complete designation to “100 tee” or assume that one thickness describes both flange and stem. A split structural tee inherits its geometry from a parent series, while a fabricated profile can use separately selected flange and stem dimensions.

## Geometry and specification fields

| Field | Decision it supports |
| --- | --- |
| Overall depth and flange width | Assembly envelope and section identity |
| Stem and flange thickness | Local geometry, connection fit and property calculation |
| Root/toe radii or weld geometry | Mating clearance and the actual cross-section |
| Length, straightness and twist | Usable stock and fabrication alignment |
| Material and route | Grade, condition, product standard/edition and inspection basis |
| Surface and ends | Finish, cut condition and retained functional surfaces |

DIN's current public record identifies **DIN EN 10055:1995-12**, adopting EN 10055:1995, for **hot-rolled steel equal-flange tees with radiused root and toes**, including dimensions and shape/dimensional tolerances. That scope is not automatically a product certification for every custom welded or split tee. A producer's use of an equivalent dimensional basis must remain distinguished from the ordered manufacturing and quality requirements. [DIN EN 10055 scope and publication](https://www.dinmedia.de/en/standard/din-en-10055/2689665)

Keep nominal dimensions and permitted deviations separate from measured results. Confirm the actual corner or seam detail where another part must seat against the stem/flange intersection. A sharp-corner CAD approximation may overstate the available mating space.

## Centroid and axes: original geometry example

Assume an ideal sharp-corner tee with **100 mm flange width, 10 mm flange thickness, 100 mm overall depth and 10 mm stem thickness**. Take the flange's outside face as the zero datum, with the stem extending away from it. Avoid counting the overlap twice:

- Flange area: `100 × 10 = 1000 mm²`, centroid 5 mm from the datum.
- Stem below the flange: `10 × 90 = 900 mm²`, centroid 55 mm from the datum.
- Total area: **1900 mm²**.

The centroid is `(1000 × 5 + 900 × 55) / 1900 = 28.684 mm` from the flange's outside face. It is therefore **71.316 mm** from the stem tip, rather than halfway through the 100 mm depth.

For a real tee, use the table or drawing with actual radii, tapers, welds, axes and centroid datum.

For the same ideal section, an assumed 2 m piece contains `1900 × 2000 = 3,800,000 mm³`, or **3.800 litres** of metal. Mass additionally needs the actual material density; this volume excludes ends, holes, finishing and dimensional variations.

## Bending direction and structural qualification

**ANSI/AISC 360-22 §F9** addresses tees and double angles loaded in their plane of symmetry. Its strength provisions consider yielding, lateral-torsional buckling, flange local buckling and local buckling of tee stems; it also distinguishes stem tension and compression cases. This is a design-rule scope, not a load rating for every T-shaped product or every loading direction. [AISC 360-22, §F9](https://vpn2.modernsteel.com/globalassets/product-files-not-searched/publications/standards/a360-22w.pdf)

Establish load direction, which face is in compression, span, restraint and connection geometry before choosing properties or assessing capacity. Rotating or reversing a tee can change the relevant behavior even if its gross area is unchanged. A stock mass or flange width alone cannot resolve stability or local connection resistance.

## Cutting, joining and final acceptance

Define the required condition after splitting, cutting, drilling, welding or straightening. The supplied profile and the finished component may have different straightness, twist and surface requirements. Agree machining allowance and retained datum surfaces before processing rather than assuming an incoming flat flange establishes final precision.

For welded profiles, specify the producer's applicable fabrication and weld-inspection basis. For later attachments, qualify the joining procedure for the actual grade and condition. Keep a dimensional catalogue entry separate from proof of a delivered heat or completed joint.

Corrosion protection, cleaning and appearance requirements belong to the selected material and service. A stainless designation needs an alloy and exposure basis; a carbon-steel tee needs its specified protection where required. The letter T provides no universal weld procedure, corrosion rating or service-temperature limit.

## Source versions and release record

The DIN record distinguishes the December 1995 national publication from EN 10055:1995. The AISC naming article is explicitly February 2012; the cited design specification is **August 1, 2022**. Montanstahl's live product page has no separately verified technical revision date. Confirm current availability and contractual editions when ordering.

Retain producer, full section designation/drawing, material specification/edition, grade/condition, route, dimensions/tolerances, length, finish, certificate and downstream fabrication/inspection record. See [Stock forms and dimensions](index.md).