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Square tube

400×400 mm Square Steel Tube

Large-section band for portal frames, plant structures and heavy transport equipment. Rolled on the 400 line, wall 8–16 mm.

122.46–192.92kg per metre (theoretical)
10.0–16.0 mmwall thickness
Made to orderavailability
15–25 days (made to order)lead time
400 mm 400 mm t 10.0–16.0

Cross-section

As drawn

Outside dimension 400×400 mm, wall 10.0–16.0 mm, corner radius 2–3 × wall.

Specification

What you get

Section400×400 mm
Wall range10.0 – 16.0 mm
Weight / m122.46 – 192.92 kg
Length6 / 9 / 12 m, or cut to length
Production line400
StandardsGB/T 6728 · GB/T 3094 · EN 10219 · ASTM A500
ToleranceWall ±10 % · squareness 90° ±1° · straightness ≤0.15 % L
CertificateEN 10204 3.1 mill certificate with every heat

Weights assume 7.85 g/cm³. Made to order — 10–25 days.

Grades

Available in

Q235BQ355BQ355CQ355DQ355EQ420B550D510L610L700L500TM700TMSPA-H

Other grades and equivalent EN / ASTM designations are quoted on request. Tell us the standard, not just the grade — we will match it.

MOQ1 bundle (≈ 2–3 t) · 1 container for export
Cutting±0.5 mm on length, deburred
CoatingHot-dip galvanising EN ISO 1461 · painting to RAL

Applications

Where 400×400 earns its keep

01

Large portal frames

Cut to length and drilled to your DXF, delivered as a bolt-on part.

02

Industrial plant structures

Mill certificate traceable to the heat, so your inspector signs off without a second trip.

03

Heavy transport equipment

Consistent wall and squareness batch to batch — welding fixtures stay in tolerance.

FAQ

Buying questions

Is 400×400 square tube available from stock?

400×400 is made to order on the 400 line, typically 10–25 days depending on grade and coating.

What is the weight of 400×400 steel tube per metre?

Between 122.46 and 192.92 kg/m across the 10.0–16.0 mm wall range (theoretical, 7.85 g/cm³).

Which grades can you roll in 400×400?

Q235B, Q355B–E, Q420B, 510L/610L/700L, 500TM/700TM and SPA-H; other grades on request.

Nearby sizes

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Need 400×400 in a specific grade?

Send the drawing or the standard — quote within 48 hours.

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