Rectangular Steel Tubes (RHS)
Cold-formed and hot-finished rectangular hollow sections from 40×20 mm to 400×200 mm — manufactured in Dammam to EN 10219, EN 10210 and ASTM A500 for beams, frames, lintels and structural fabrication.
Standards
EN 10219EN 10210 · ASTM A500 · BS 4848
Section
40×20 – 400×200mm rectangular (custom on request)
Finish
Black / GalvMill, pre-galv, hot-dip, primed
Lead time
1–2 weeksStock items · custom 3–6 wks
What is a rectangular hollow section?
A rectangular tube — or rectangular hollow section (RHS) — is a closed structural profile with two longer sides and two shorter sides and a uniform wall thickness. Concentrating material in the longer faces makes RHS exceptionally efficient about its major axis, so it carries more bending and deflects less than a square or round section of the same weight when loaded in one direction.
That makes rectangular tube the natural choice for beams, lintels, purlins and portal-frame rafters — anywhere load is predominantly vertical. Its flat, parallel faces also make it one of the easiest sections to weld, bolt, clad and connect on site.
Rouad Steel produces rectangular tube on dedicated ERW forming lines: steel strip is cold-roll-formed, high-frequency welded along the seam, then sized into a precise rectangular profile. Hot-finished sections (EN 10210) are available where tighter corner radii and relieved residual stresses are specified.
Mill test certificates (EN 10204 3.1) accompany every batch, covering chemical composition, mechanical properties and dimensional tolerances.
Rectangular vs square hollow section
Both are box sections cut from the same grades and standards — the difference is geometry, and it decides where each one performs best.
A side-by-side comparison to help you specify the right profile for your load case.
→ scroll table| Feature | Rectangular tube (RHS) | Square tube (SHS) |
|---|---|---|
| Cross-section | Two long + two short sides | Four equal sides |
| Strength axis | Stronger about the major (long) axis | Equal strength both axes |
| Best for | Beams, lintels, purlins, rafters | Columns, posts, frames |
| Load direction | Predominantly one direction | From any direction |
| Bending efficiency | Higher in the plane of the long face | Uniform, lower than RHS on long axis |
| Typical sizes | 40×20 – 400×200 mm | 20×20 – 200×200 mm |
| Connections | Flat parallel faces — easy to weld/bolt | Flat faces — easy to weld/bolt |
| Standards & grades | EN 10219 / 10210 · S235 / S355 | EN 10219 / 10210 · S235 / S355 |
Rule of thumb: choose RHS when load is mostly vertical (a beam), and SHS when load can arrive from any direction (a column). Not sure which suits your design? Talk to our technical desk.
Major & minor axis — get the orientation right
Because a rectangular section is not symmetrical, how you orient it changes its capacity dramatically. The major axis (X–X) runs through the long faces and carries the most bending; the minor axis (Y–Y) runs through the short faces and is weaker.
For a beam, lay the section so the long face is vertical — in the plane of bending — to use the full depth of the profile. Stand it on the short face only when lateral stability or a low build-up height matters more than capacity.
Quick check: for the same weight, a 100×50 RHS on its long edge is far stiffer as a beam than the same tube laid flat — orient the depth in line with the load.
Why engineers choose rectangular tube
A box section tuned for bending — efficient, flat-faced and easy to build with.
High major-axis capacity
Material in the long faces gives a high section modulus about the major axis — more bending strength per kilo as a beam.
Stiff, low-deflection beams
Greater depth in the plane of load means smaller deflections and longer clear spans without extra steel.
Easy to fabricate
Flat, parallel faces make welding, bolting and flush connections fast — and the wide face is simple to clad and fix.
Clean architectural look
Sharp, uniform faces suit exposed steelwork, frames, balustrades and façades with minimal finishing.
Corrosion options
Pre-galvanized, hot-dip galvanized and primed finishes extend service life in exposed and humid environments.
Predictable tolerances
Tight control on side lengths, squareness and straightness for repeatable, drama-free fit-up on site.
Cold-formed, hot-finished & pre-galvanized RHS
Cold-formed (EN 10219)
Roll-formed and ERW-welded at ambient temperature. The most economical, widely-used RHS for general structural and fabrication work.
- Grades S235JRH / S355J2H
- Sharp, consistent corners
- Best value for volume orders
Hot-finished (EN 10210)
Formed and normalized at elevated temperature for relieved residual stress and uniform properties — preferred for heavy or dynamically loaded beams.
- Superior toughness & fatigue
- Tighter corner radii
- Ideal for seismic / cyclic loads
Pre-galvanized
Formed from zinc-coated strip for ready corrosion resistance, or hot-dip galvanized after fabrication for the heaviest-duty exposure.
- Pre-galv & hot-dip options
- Outdoor & humid environments
- Lower lifecycle maintenance
Rectangular tube sizes & weights
Nominal mass per metre for carbon-steel RHS to EN 10219. Other sizes, walls and grades available — ask our team.
→ scroll table| Section (H × B) | Wall t (mm) | Mass (kg/m) | Standard length |
|---|---|---|---|
| 40 × 20 mm | 2.0 | 1.68 | 6 m / cut-to-length |
| 40 × 20 mm | 2.5 | 2.03 | — |
| 40 × 20 mm | 3.0 | 2.36 | — |
| 50 × 25 mm | 2.0 | 2.15 | 6 m / cut-to-length |
| 50 × 25 mm | 2.5 | 2.62 | — |
| 50 × 25 mm | 3.0 | 3.07 | — |
| 50 × 30 mm | 2.5 | 2.82 | 6 m / cut-to-length |
| 50 × 30 mm | 3.0 | 3.30 | — |
| 50 × 30 mm | 4.0 | 4.20 | — |
| 60 × 40 mm | 2.5 | 3.61 | 6 m / cut-to-length |
| 60 × 40 mm | 3.0 | 4.25 | — |
| 60 × 40 mm | 4.0 | 5.45 | — |
| 60 × 40 mm | 5.0 | 6.56 | — |
| 80 × 40 mm | 3.0 | 5.34 | 6 m / cut-to-length |
| 80 × 40 mm | 4.0 | 6.97 | — |
| 80 × 40 mm | 5.0 | 8.54 | — |
| 80 × 40 mm | 6.0 | 10.0 | — |
| 80 × 60 mm | 3.0 | 6.28 | 6 m / cut-to-length |
| 80 × 60 mm | 4.0 | 8.23 | — |
| 80 × 60 mm | 5.0 | 10.1 | — |
| 80 × 60 mm | 6.0 | 11.9 | — |
| 100 × 50 mm | 3.0 | 6.71 | 6 m / cut-to-length |
| 100 × 50 mm | 4.0 | 8.78 | — |
| 100 × 50 mm | 5.0 | 10.8 | — |
| 100 × 50 mm | 6.0 | 12.7 | — |
| 100 × 60 mm | 3.0 | 7.22 | 6 m / cut-to-length |
| 100 × 60 mm | 4.0 | 9.48 | — |
| 100 × 60 mm | 5.0 | 11.7 | — |
| 100 × 60 mm | 6.0 | 13.8 | — |
| 100 × 60 mm | 8.0 | 17.8 | — |
| 120 × 60 mm | 4.0 | 10.7 | 6 m / cut-to-length |
| 120 × 60 mm | 5.0 | 13.3 | — |
| 120 × 60 mm | 6.0 | 15.8 | — |
| 120 × 60 mm | 8.0 | 20.7 | — |
| 120 × 80 mm | 4.0 | 11.9 | 6 m / cut-to-length |
| 120 × 80 mm | 5.0 | 14.8 | — |
| 120 × 80 mm | 6.0 | 17.5 | — |
| 120 × 80 mm | 8.0 | 22.6 | — |
| 140 × 80 mm | 5.0 | 16.3 | 6 m / cut-to-length |
| 140 × 80 mm | 6.0 | 19.4 | — |
| 140 × 80 mm | 8.0 | 25.1 | — |
| 140 × 80 mm | 10.0 | 30.4 | — |
| 150 × 100 mm | 5.0 | 18.6 | 6 m / cut-to-length |
| 150 × 100 mm | 6.0 | 22.1 | — |
| 150 × 100 mm | 8.0 | 28.7 | — |
| 150 × 100 mm | 10.0 | 34.8 | — |
| 150 × 100 mm | 12.0 | 40.4 | — |
| 160 × 80 mm | 5.0 | 17.8 | 6 m / cut-to-length |
| 160 × 80 mm | 6.0 | 21.2 | — |
| 160 × 80 mm | 8.0 | 27.6 | — |
| 160 × 80 mm | 10.0 | 33.7 | — |
| 200 × 100 mm | 5.0 | 22.6 | 6 m / cut-to-length |
| 200 × 100 mm | 6.0 | 26.8 | — |
| 200 × 100 mm | 8.0 | 35.1 | — |
| 200 × 100 mm | 10.0 | 43.1 | — |
| 200 × 100 mm | 12.0 | 50.7 | — |
| 200 × 120 mm | 6.0 | 28.7 | 6 m / cut-to-length |
| 200 × 120 mm | 8.0 | 37.6 | — |
| 200 × 120 mm | 10.0 | 46.3 | — |
| 200 × 120 mm | 12.0 | 54.6 | — |
| 250 × 150 mm | 6.0 | 36.2 | 6 m / cut-to-length |
| 250 × 150 mm | 8.0 | 47.7 | — |
| 250 × 150 mm | 10.0 | 58.8 | — |
| 250 × 150 mm | 12.0 | 69.6 | — |
| 250 × 150 mm | 16.0 | 89.0 | — |
| 300 × 200 mm | 8.0 | 59.3 | 6 m / cut-to-length |
| 300 × 200 mm | 10.0 | 73.6 | — |
| 300 × 200 mm | 12.0 | 87.4 | — |
| 300 × 200 mm | 16.0 | 114 | — |
| 400 × 200 mm | 8.0 | 72.8 | 6 m / cut-to-length |
| 400 × 200 mm | 10.0 | 90.2 | — |
| 400 × 200 mm | 12.0 | 107 | — |
| 400 × 200 mm | 16.0 | 139 | — |
Weights are indicative and rounded. H = depth (long side), B = width (short side). Tolerances on mass, dimensions and straightness are per the relevant standard. Need a stock list or a section not shown here? Contact our sales desk.
How to choose the right rectangular tube
Four quick checks that get you to the correct section — share these with your quote and we will confirm the rest.
Define the load & span
Work out the load it must carry and the clear span. Heavier loads or longer spans call for a deeper section (a larger H dimension).
Pick depth, then width
Choose the depth (H) for bending strength, then the width (B) for lateral stability, fixing room and the look you need.
Set the wall thickness
Thicker walls add capacity and weldable material. Match thickness to load, connection detail and any corrosion allowance.
Choose grade & finish
S275 or S355 for most structures; add pre-galv or hot-dip galvanizing for outdoor service. Specify the standard (EN 10219 / 10210).
Where rectangular tube is used
From structural beams to architectural metalwork, rectangular tube is the section of choice wherever load runs mainly one way.
- Beams, purlins & rafters
- Lintels over door & window openings
- Portal-frame rafters & columns
- Mezzanine & platform beams
- Goalpost & gantry frames
- Truck, trailer & chassis rails
- Crane runways & conveyor supports
- Bridge, walkway & handrail members
- Signage gantries & billboards
- Display stands, racking & shelving
- Solar & PV mounting beams
- Furniture & equipment frames
Need rectangular tube for a project?
Send us your cutting list or BOQ — we reply with pricing, weights and mill test certificates within 24 hours.
Specifications we manufacture to
| Standard | Type | Common grades | Notes |
|---|---|---|---|
| EN 10219 | Cold-formed welded | S235JRH, S355J2H | General structural RHS |
| EN 10210 | Hot-finished welded | S275J2H, S355J2H | Heavy / dynamic loads |
| ASTM A500 | Cold-formed welded | Gr B, Gr C | US structural tubing |
| BS 4848-2 | Hot-finished | S275, S355 | Legacy UK projects |
| ASTM A1085 | Cold-formed welded | Gr A | Tighter tolerances · on request |