Expanded metal, epoxy screen or welded mesh?
The first question is whether the support layer goes through the pleater with the media. If it does, choose expanded metal, epoxy coated screen, PP mesh or annealed welded mesh. If it carries structural load as a core, cage or backing grid, choose standard welded mesh.
| Expanded metal | Epoxy coated screen | Welded mesh | PP mesh | |
|---|---|---|---|---|
| How it is made | Slit and stretched from one coil; no joints | Plain-woven wire, epoxy powder coated | Wires resistance-welded at each crossing | Woven polypropylene monofilament |
| Pleats with the media | Yes, thin gauges | Yes | Annealed soft grade only | Yes |
| Main role | Pleat support and liners | Pleat support and protection layer | Center cores, outer cages, backing grids | Metal-free pleat support |
| Edge after slitting | Clean, no loose wires | Clean; coating locks intersections | Cut wire ends at the edge | Soft edge, no sharp wires |
| Opening shape | Diamond, 2 x 3 to 23 x 38.6 mm | Square, 14 x 14 to 30 x 30 mesh | Rectangular or square, 1/2 x 1 in and 1 x 1 in | 905 µm or 517 x 456 µm |
| Materials | Galvanized, aluminium, stainless, copper, nickel, titanium | Woven wire, epoxy coated | Hot-dip galvanized, stainless 304/316 | Polypropylene, black or white |
| Roll width | 7-49 in (178-1,250 mm) | 8-52 in (200-1,300 mm) | 7-48 in (178-1,219 mm) | 127 and 260 cm |
Quick decisions
- Pleated HVAC panel or engine air filter: epoxy coated screen or thin expanded metal laminated with the media.
- Pulse-cleaned dust collector cartridge: expanded metal or epoxy screen for the pleats; welded mesh or expanded metal for the inner core and outer liner.
- Hydraulic or lube oil element: epoxy coated screen on the pleats; welded mesh rolled into the center tube.
- Bag, pad or panel pre-filter: welded mesh as a flat backing grid.
- Metal-free or incinerable filter, or acidic and humid air: PP support mesh.
Need a polymer support layer instead of metal? See polypropylene support mesh.
Wire gauge reference (AWG)
American Wire Gauge, calculated from the ASTM B258 definition. Gauges used in the epoxy screen and welded mesh tables.
| AWG | inch | mm |
|---|---|---|
| 16 | 0.0508 | 1.291 |
| 18 | 0.0403 | 1.024 |
| 20 | 0.0320 | 0.812 |
| 22 | 0.0253 | 0.644 |
| 24 | 0.0201 | 0.511 |
| 30 | 0.0100 | 0.255 |
| 31 | 0.00893 | 0.227 |
| 32 | 0.00795 | 0.202 |
| 33 | 0.00708 | 0.180 |
Related support media
Frequently asked questions
What is the difference between expanded metal and epoxy coated screen?
Expanded metal is slit and stretched from one coil and has no joints; epoxy coated screen is woven wire whose crossings are locked by the coating. Both pleat with the media; expanded metal offers larger diamond openings, epoxy screen a finer square mesh.
When should I use welded mesh?
Use welded mesh where the layer carries structural load: center cores, outer cages and backing grids. Use the annealed soft grade only where welded mesh must be pleated.
Is there a metal-free filter support option?
Yes. Polypropylene support mesh is metal-free and suits humid, acidic or incinerable filters.
Not sure which one fits?
Send the filter type, media, pleat height and operating conditions. Our engineers recommend a support layer and send samples.