Welded vs press-locked bar grating
Construction is the first decision in a bar grating RFQ. Welded is the industrial default; press-locked (swage-locked) is the architectural and flush-face choice. This page compares them across 12 dimensions with the numbers a specifier needs.
Key takeaways
- Welded joins bars by electric-resistance welding at every intersection; press-locked punches a slot in the bearing bar and swages the cross bar into it.
- Welded carries 100% of NAAMM MBG 531 tabulated load; press-locked 92–95% of the same bearing-bar geometry.
- Welded is 10–20% cheaper per m² in steel; the gap narrows in aluminum and stainless.
- Press-locked wins when flush top/bottom faces, tight geometry, or aluminum/SS are required.
Side-by-side comparison (12 dimensions)
| Attribute | Welded bar grating | Press-locked bar grating |
|---|---|---|
| Joining method | Electric resistance forge weld at every intersection | Cross bar pressed into punched slot in bearing bar |
| Top surface | Cross bar protrudes ~0.8 mm above bearing bar top | Flush: cross bar top flush with bearing bar top |
| Bottom surface | Cross bar exposed below bearing bar | Flush on both sides |
| Relative load capacity | 100% of NAAMM MBG 531 value | 92–95% (net section reduced by slot) |
| Joint integrity | Metallurgical bond; shear >120 kN at 6 mm bar | Mechanical interlock; shear ~75–90 kN |
| Tolerance (flatness) | ± 5 mm / m | ± 2 mm / m (tighter) |
| Cross-bar spacing options | 50 or 100 mm (2" or 4") | 50, 60, 75, 100 mm (wider range) |
| Bearing-bar pitch | 19–40 mm typical | 15–50 mm (wider range) |
| Suits aluminum / stainless? | Harder: aluminum weldability; stainless post-weld passivation | Ideal: no welding, no heat-affected zone |
| Architectural appearance | Utilitarian, industrial | Clean flush geometry; preferred on facades, canopies |
| Relative cost (steel, m²) | 1.00 × (baseline) | 1.10–1.20 × baseline |
| Typical lead time | 10–15 working days | 15–20 working days |
When to choose welded bar grating
- Industrial walkways, platforms, catwalks, mezzanines.
- Heavy-duty and forklift trench covers (load class D400 and above).
- Projects specifying ANSI/NAAMM MBG 531 and standard 19-W-4 / 30-100 mesh.
- Budget-driven RFQs where the extra 10–20% of press-locked isn't justified.
- Hot-dip galvanized steel — welded's robust geometry holds zinc well.
See our welded bar grating product page for geometry, finish, and load tables.
When to choose press-locked grating
- Architectural facades, canopies, sunshades, ventilation screens.
- Stair treads visible from below where protruding cross bars are unacceptable.
- Aluminum and stainless-steel grating — avoids welding complications.
- Curved, tapered, or irregular panels where tight cross-bar tolerance matters.
- Applications with small-diameter wheels (carts, trolleys) that catch on protruding cross bars.
Frequently asked questions
- Is welded or press-locked grating stronger?
- Welded. At identical bearing-bar depth, welded carries roughly 100% of NAAMM MBG 531 tabulated load; press-locked with bar pressed into a slot is typically rated at 92–95% because the cross bar reduces the bearing bar's net section.
- Why specify press-locked instead of welded?
- Press-locked delivers a flush top and bottom surface, cleaner appearance, and tight cross-bar tolerance. Use it for architectural facades, stair treads visible from below, curved or tapered panels, and aluminum grating where welding is harder.
- Are both patterns hot-dip galvanized?
- Yes. Both can be galvanized per ASTM A123 / ISO 1461 with 80–100 µm zinc. Press-locked panels need extra drainage holes at frame details because the flush faces trap bath drip-off.
- Which is cheaper?
- Welded, typically 10–20% less per m² at equivalent bearing-bar depth and mesh. The gap narrows in aluminum or stainless where press-locked lines are optimized.
- Can press-locked grating be used for forklift traffic?
- Yes, with heavy bars (50–65 mm × 6 mm) and tight cross-bar spacing (50 mm). For repeat H20 truck traffic we still recommend heavy-duty welded because the welded joint withstands fatigue better.
Specify with confidence
Tell us span, load, and mesh — we'll send a welded vs press-locked price side by side within 12 hours.