Factory-direct steel gratings & stair treads, shipped worldwide
Hot-Dip Galvanized Grating
Hot-Dip Grating: every batch ships with traceable mill test certificates.
Itemized quote within 24 hours · Free drawing review included
Coating sampled every batch
Thickness checks to ASTM A123 / ISO 1461
Certified & tested
Reports on request, MTC with every order
Samples in 5–7 days
Production in 15–25 working days, HDG included
FOB Tianjin
Shipped worldwide, EXW / CIF negotiable
Material comparison
Steel Grating Material Comparison
When a drawing calls for hot dip galvanized steel grating, the coating is doing the corrosion work — the panel underneath is still carbon steel. Here is how the four materials we run compare, and where the galvanized row wins on cost and delivery.
| Material | Corrosion resistance | Typical environment | Relative cost | Base steel |
|---|---|---|---|---|
| Carbon steel, black | Needs shop primer or paint; bare steel is for dry indoor duty only | Dry indoor platforms, painted service, temporary works | Lowest | Q235B |
| Hot-dip galvanized Q235B | Corrosion-Resistant zinc coating, metallurgically bonded — covers cut edges and welds | Outdoor walkways, platforms, trench covers, wet plant floors | Moderate | Q235B |
| Stainless SS304 | Corrosion-Resistant in fresh water, food washdown and mild chemical duty | Food plants, washdown floors, general wet areas | Higher | SS304 |
| Stainless SS316 | Best of the range against chlorides and saline atmospheres | Marine, coastal, brine and chemical zones | Highest | SS316 |
Not sure which material your environment needs? Send your drawings — we will spec it inside the 24-hour quote.
How the coating is applied and verified
Inside the Kettle: Prep, Immersion, Verification
Hot dip galvanized grating is coated after fabrication — panels are cut, welded and banded first, then dipped whole, so the zinc covers every cut edge, weld point and banding edge that a pre-galvanized sheet can never protect.
1 · Surface preparation
Degreasing, acid pickling and fluxing strip mill scale and shop soils off the Q235B bars. Only chemically clean steel reacts with molten zinc to form a sound, continuous coating.
2 · Kettle immersion
Open grating panels vent and drain: air escapes through the mesh as the panel enters, zinc flows fully around every bar and weld, and the grid lets excess zinc run back as panels are withdrawn at a controlled angle — no trapped pockets, no pooling.
3 · Thickness sampling & release
No galvanized batch is released unsampled. Magnetic-gauge thickness readings are taken against ASTM A123 / ISO 1461 requirements — stage four of our five-stage QC plan — before panels return for final inspection.
The full galvanizing cycle runs 2–3 days at our certified partner plant near the mill — already counted inside your 15–25 day production window, never added on top of it.
Why specify galvanized
Why Specifiers Choose Hot-Dip Galvanized Grating
Batch-tested, document-backed
Coating thickness is sampled on every galvanized batch and the Q235B heat is traceable — you receive mill test certificates (EN 10204 Type 3.1) with every shipment, and material certs are ready to preview with your quote.
Corrosion-Resistant for wet sites
The zinc layer is bonded to the steel, not painted on it — an anti-rust barrier for rain, splash, de-icing salt and washdown duty on outdoor walkways, trench covers and plant platforms.
Any size, made to spec
19W4 stock designations or fully custom panels cut and banded to your drawings before dipping — from small trial orders to full containers, direct from the mill with no middlemen.
Applications
Where Galvanized Grating Earns Its Zinc
Anywhere steel meets weather, de-icing salt or washdown water, hot dip galvanized grating is the default specification — carbon-steel strength with a coating that seals every cut edge.
Outdoor walkways & platforms
Rain, snow and ice shed straight through the mesh; the coating holds year-round.
Municipal trench & tree-pit covers
Road-salt and stormwater duty — the classic HDG specification for public works.
Exterior & escape stair treads
Serrated or plain treads galvanized after banding, nosing edges included.
Fences, gates & screens
Galvanized grid panels as perimeter infill — open, rigid and weatherproof.
Specifications
Hot-Dip Galvanized Grating Specifications
| Parameter | Range |
|---|---|
| Core material | Q235B carbon steel · SS304 / SS316 optional |
| Bearing bar | 20×3 mm to 100×8 mm, plain or serrated |
| Bar spacing | 30 / 40 / 60 mm centers |
| Panel width | Up to 1.25 m |
| Panel length | Up to 6 m |
| Coating sequence | Hot-dip galvanized after fabrication — cut edges, welds and banding coated |
| Coating standards | ASTM A123 / ISO 1461, thickness sampled per batch |
| Stock designation | 19W4 and custom equivalents |
Materials & test documents
The zinc protects the steel; the documents prove both. Every Q235B heat is checked against its mill certificate at goods-in — the first of our five QC stages — and hot dip galvanized grating leaves with paperwork you can verify:
- Mill test certificates (EN 10204 Type 3.1) with every shipment
- Galvanizing batch thickness-sampling record
- Factory inspection report with every shipment
- Declaration of Conformity prepared per order destination
Standards & compliance
ASTM A123, ISO 1461 and the Paper Trail Behind the Zinc
We produce to these standards and evidence them with documents — the coating is judged by measurement, not adjectives. The chain runs from incoming steel to released batch: MTC verification at goods-in, first-article check, weld inspection, post-galvanizing thickness sampling, final inspection with the shipment report.
ASTM A123
The North American standard for zinc coatings on fabricated iron and steel — coating thickness judged by steel section category, which is exactly how our per-batch sampling is structured.
ISO 1461
The international counterpart for hot dip galvanized coatings on fabricated articles — minimum coating requirements on the finished part, verified by sampling rather than assumed from the chemistry.
EN 10204 Type 3.1
The document standard behind the mill test certificate that traces the Q235B heat. Certified & tested, reports on request — the galvanizing batch record sits beside it as coating evidence.
Standards hub — market-by-market comparison → · Choosing coating expectations by environment →
Custom made
Custom Panels, Dipped After Fabrication
Send your drawing
Panel sizes, load specs, coating class, quantities — or just photos and a sketch. Drawing review is free.
Quote within 24 hours
Itemized, FOB Tianjin as standard — EXW or CIF on request. Small trial orders welcome, no middlemen.
Samples in 5–7 days, production in 15–25
Working days after drawing confirmation — the 2–3 day galvanizing cycle is already inside the window. Installation drawings and fixing layout ship with the order.
Factory-direct quote
Get a Factory Quote
Send your hot-dip galvanized grating specs — an itemized quote lands within 24 hours, free drawing review included.
- Coating thickness sampled on every galvanized batch — ASTM A123 / ISO 1461
- Ships with mill test certificates (EN 10204 Type 3.1) with every shipment — material certs ready to preview
- Factory audits welcome — see the lines and the coating records 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 standards govern hot-dip galvanized grating?
Coatings are produced to ASTM A123 and ISO 1461, the two governing standards for hot-dip galvanized coatings on fabricated steel. Thickness is verified by sampling on every galvanized batch — stage four of our five-stage QC plan — and reports are available on request.
How long does the hot-dip galvanizing cycle take?
Panels cycle through our certified galvanizing partner near the mill in 2–3 days, and that time is already counted inside the 15–25 working-day production window. Samples ship in 5–7 working days, galvanizing included.
How does open mesh behave in the zinc kettle?
It vents and drains. Air escapes through the mesh as the panel enters, zinc flows fully around every bar, weld point and banded edge, and the open grid lets excess zinc drain back as panels are withdrawn — no trapped pockets, no pooling.
Related pages
Related Galvanized Grating Pages
HDG Grating
The process story — what the zinc bond does at the steel surface.
View page →Grating HDG Specifications
Choosing coating expectations by environment class.
View page →Galv Grating
The galvanized line overview — HDG as the default weather protection.
View page →Galvanized Steel Grating
Q235B core plus HDG finish — coating checked per batch.
View page →Galvanized Steel Bar Grating
Ordering angle — sizes, banding options, quote checklist.
View page →Galvanized Grid
Grid formats with zinc protection for outdoor grids and fences.
View page →