40 mesh brass wire mesh has 40 openings per linear inch. Woven to ASTM E2016 / ISO 9044 with a standard aperture of 0.39 mm (385 µm), this page lists the controlling specification — wire diameter, aperture, micron rating, open area and cloth weight — together with the wire options available at this count and the duties it is normally specified for.
40 Mesh Specification Row (ASTM E2016 / ISO 9044)
| Mesh count | Wire diameter (mm) | Aperture (mm) | Micron rating (u00b5m) | Open area (%) | Alloy |
|---|---|---|---|---|---|
| 40-Mesh | 0.250 | 0.385 | 385 | 36.8 | CuZn35 (H65) |
40 Mesh to Micron & Aperture
| Openings per inch | 40 |
|---|---|
| Aperture (opening width) | 0.39 mm |
| Micron rating | 385 µm |
| Standard wire diameter | 0.25 mm |
| Open area | 36.8 % |
Aperture = (25.4 mm ÷ mesh count) − wire diameter. The micron rating equals the aperture in micrometres; actual retention also depends on particle shape and cake formation.
Wire Diameter Options at 40 Mesh
| Option | Wire dia | Aperture | Micron | Open area | Weight (SS) |
|---|---|---|---|---|---|
| Heavy wire | 0.325 mm | 0.310 mm | 310 µm | 23.8 % | 2.18 kg/m² |
| Standard wire | 0.250 mm | 0.385 mm | 385 µm | 36.8 % | 1.29 kg/m² |
| Fine wire | 0.188 mm | 0.448 mm | 448 µm | 49.7 % | 0.72 kg/m² |
Heavier wire adds strength and abrasion life but closes the aperture; finer wire opens the aperture and raises throughput at the cost of durability. Specify mesh count AND wire diameter to fix the aperture unambiguously.
Open Area & Flow at 40 Mesh
The standard 40 mesh weave presents an open area of about 36.8%. At this count the mesh presents little flow resistance; selection is normally driven by particle retention and mechanical strength rather than pressure drop.
40 Mesh Cloth Weight
Standard 40 mesh stainless cloth weighs approximately 1.29 kg/m² (density 7.93 g/cm³ basis; brass and copper weave roughly 10% heavier, aluminum about one third). Use this figure for roll handling and freight estimation.
Typical Applications for 40 Mesh Brass Wire Mesh
40 mesh brass wire mesh is commonly specified for general straining and sieving, paint and coating filtration, grease filters, insect screening, grain cleaning and pre-filtration ahead of fine media.
When to Step Up or Down from 40 Mesh
Move to 50 mesh when particles are passing that must be retained; drop back to 30 mesh when the element blinds too quickly or the pressure drop is excessive. In a multi-layer pack, pair this count with a coarser support mesh downstream to carry the pressure load.
What Brass Wire Mesh Does
Screening, sieving and decorating with woven brass cloth that is spark-resistant, non-magnetic and keeps a warm gold color.
Fitting & Care
- Cut with sharp snips and fold edges back; brass work-hardens and cracks if bent repeatedly.
- Clean decorative brass mesh with mild soap; avoid ammonia-based cleaners entirely.
