Factory-direct steel gratings & stair treads, shipped worldwide
I-Bar Grating
I bar grating answered by factory engineers. Full data, free.
Itemized quote within 24 hours · Free drawing review included
In-house weld & press lines
Flat-bar panels formed and locked under one roof
Certified & tested
Reports on request, MTC with every order
Samples in 5–7 days
Production in 15–25 working days
FOB Tianjin
Shipped worldwide, EXW / CIF negotiable
Bearing-bar sections compared
Flat Bar vs I-Section vs Round Bar Grating
I bar grating is defined by its bearing-bar cross-section, not by a process. Here is how the three sections you can specify compare — with an honest note on which one our stock program actually runs.
| Dimension | Rectangular Flat Bar | I-Section Bearing Bar | Round Bar Grating |
|---|---|---|---|
| Section shape | Plain rectangular bar, depth × thickness | Two flanges joined by a central web | Round bars — used mainly as cross bars |
| Steel at depth | More mass needed as the bar gets deeper | Same mass works harder — steel sits out in the flanges | Stiffness set by bar diameter |
| Span behavior | Proven default; load tables per spacing class | Better stiffness-to-weight over longer spans | Strongest in the transverse direction |
| Open area | High at 30 / 40 / 60 mm centers | Similar openings, slimmer shadow line | Distinct open pattern for screens |
| Typical use | Platforms, walkways, trench covers | Long-span walkways, weight-sensitive floors | Cross bars, architectural screens |
| Our supply basis | Stock line — 20×3 to 100×8 mm flat bars, in-house | Quoted per project — send the section | Twisted square or round cross bars, per spec |
Not sure which section your spans need? Send your drawings — we will spec it inside the 24-hour quote.
The section physics
Why an I-Shaped Bar Spans Better Than a Flat One
1 · Same depth, smarter steel
Both sections can stand at the same height. The flat bar spends its steel evenly across the thickness; the I-style bar concentrates it into two flanges at the outer edges, joined by a thin web.
2 · Distance does the work
In bending, the steel furthest from the center of the section carries the most load. Flanges push that steel to the edges, so for the same mass per metre the I-section behaves stiffer over the span — better deflection behavior, lighter panels, fewer support beams under long walkways.
3 · Our honest supply note
Our stock program is rectangular flat bearing bars, 20×3 mm to 100×8 mm. I-section style bearing bars are quoted per project on our in-house lines — tell us the depth, flange and web in the RFQ and we will confirm what we can run. No invented I-bar stock list here.
A note on names: many buyers say i-bar when they mean deeper rectangular flat bars, and others mean a true I-shaped section. We map both — state either in your quote request and the engineers answer with the exact section.
Why specify with us
Why Buyers Ask Dengtai About I Bar Grating
Full specs, free help
Factory engineers answer i bar grating questions with data, not guesses — section options, steel grating thickness and spacing classes, finish choices and the load tables behind them.
Samples in 5–7 days, small MOQ
Sample panels come off the running line in 5–7 working days, and small trial orders are welcome — test the section and the finish before you commit to a container.
Factory-direct, custom sections
No trading-company margin. Panels are cut, banded and galvanized to your drawings, FOB Tianjin with an itemized quote — shipped worldwide.
Applications
Where I Bar Grating Earns Its Section
Wherever spans get long or panel weight matters, buyers move from flat bars to deeper sections — and ask for i bar grating by name.
Long-span access walkways
Deeper bearing sections carry foot traffic across wider clear spans with fewer support beams.
Mezzanine floors
Weight-efficient flooring trims dead load on the supporting frame and the steel budget with it.
Galvanized outdoor platforms
Weather-exposed plant flooring with ASTM A123 / ISO 1461 hot-dip galvanizing.
Facades & screens
Slim shadow lines and open mesh make I-style bars a favorite for architectural screening.
Specifications
I Bar Grating Specifications — What We Actually Run
| Parameter | Range |
|---|---|
| Stock bearing bar | Rectangular flat bar, 20×3 mm to 100×8 mm, plain or serrated |
| I-section bearing bar | Quoted per project — send depth, flange and web dimensions |
| Steel grating thickness | 3–8 mm bearing-bar thickness in size call-outs |
| Bar spacing | 30 / 40 / 60 mm centers |
| Cross bar | Twisted square or round, per specification |
| Panel width | Up to 1.25 m |
| Panel length | Up to 6 m |
| Materials | Q235B carbon steel · SS304 / SS316 stainless |
| Surface | Black or hot-dip galvanized (ASTM A123 / ISO 1461) |
| Designation help | 19W4 and custom equivalents |
Materials & test documents
Every heat of Q235B, SS304 or SS316 enters production with its mill test certificate verified at goods-in — the first of our five QC stages. Load and deflection tables for your exact section are provided with your quote, not guessed on a web page:
- Mill test certificate to EN 10204 Type 3.1
- Factory inspection report with every shipment
- Declaration of Conformity prepared per order destination
Standards & compliance
Produced to Recognized Standards — Documents on Request
ANSI / NAAMM MBG 531
Bar grating produced to MBG 531 reference practice, with joint inspection on our five-stage QC plan.
ASTM A123 / ISO 1461 HDG
Galvanized coating thickness checked by sampling on every galvanized batch before panels are released.
CE & SGS tested
Certified & tested, reports on request — we show documents you can verify, not a certificate wall.
Custom made
Custom Sections or Stock Flat Bars — Both Start the Same Way
Send your section
Depth, flange and web for I-style bars — or the flat-bar size class. Photos and sketches work too; drawing review is free.
Quote within 24 hours
Itemized, FOB Tianjin as standard — EXW or CIF on request. Small trial orders welcome.
Samples in 5–7 days, production in 15–25
Working days after drawing confirmation, hot-dip galvanizing included. Installation drawings and fixing layout ship with the order.
Factory-direct quote
Get a Factory Quote
Send your drawings for i bar grating — the quote lands within 24 hours, free drawing review included.
- Five-stage QC, from MTC verification at goods-in to final inspection
- DoC, MTC EN 10204 3.1 and inspection report with every order
- Factory audits welcome — see the lines before you commit
Prefer to talk? WhatsApp us or sales@dtsteelladder.com
Request your quote
Five fields — we do the rest.
FAQ
Frequently Asked Questions
What is I-bar grating?
I-bar grating carries the floor on an I-shaped bearing bar: two flanges joined by a web. For the same steel mass, the flanges sit further from the center of the section, so the panel spans better than a flat bar of equal weight. Many buyers also say i-bar when they mean deeper rectangular flat bars — we quote both.
Do you keep I-section bearing bars in stock?
No — our stock line runs rectangular flat bearing bars from 20×3 mm to 100×8 mm, at 30 / 40 / 60 mm centers. I-section style bearing bars are quoted per project: tell us the depth, flange and web dimensions in the RFQ and we will confirm the run.
How fast can I get a quote and samples?
Drawings are reviewed free and an itemized quote lands within 24 hours. Samples ship in 5–7 working days, production in 15–25 working days after drawing confirmation, hot-dip galvanizing included. FOB Tianjin as standard, EXW or CIF negotiable.
Related pages
Related Specification Pages
Bearing Bar Grating
The flat bearing-bar range — heights, thickness and centers.
View page →Twisted Bar Grating
Twisted square and round cross bars — how the mesh is locked.
View page →Heavy-Duty Bar Grating
Bar construction for wheel loads and heavy plant floors.
View page →Grating Load Bar
Load bars explained — spans, uniform and point loads.
View page →Structural Steel Grating
Structural steel grades behind load-bearing grating panels.
View page →1 Inch Bar Grating
The 25 mm deep class — a common i-bar look-alike.
View page →