ASTM A740 covers the requirements for welded wire mesh rolls. Reproduced below: the complete specification table, the tolerance classes, and the companion and equivalent standards referenced when ordering to this document.
ASTM A740 — Scope
ASTM A740 specifies the designation system, dimensions and tolerances of welded wire mesh rolls — mesh count or nominal opening, wire diameter and the permissible aperture deviations. Alloy chemistry, mechanical testing and delivery condition are governed by separate documents in the same standards family.
Tolerance Classes
ASTM A740 defines tolerance limits on the average aperture and on the maximum single aperture, tightening as the aperture gets finer. For test-sieve duty the tighter ISO 3310-1 tolerances apply instead of the general cloth tolerances — specify sieve grade explicitly if the mesh will be used for particle-size analysis.
Specifications Defined by ASTM A740
| Opening (mm) | Wire diameter (mm) | Format | Standard size | Reference standard |
|---|---|---|---|---|
| 12.7x12.7 | 1.6 | Panel / roll | 1.0 x 2.0 m | EN 10223-7 |
| 25.4x25.4 | 2.0 | Panel / roll | 1.0 x 2.0 m | EN 10223-7 |
| 50.8x50.8 | 2.5 | Panel | 1.2 x 2.4 m | EN 10223-7 |
| 50x50 | 4.0 | Panel | 2.0 x 3.0 m | EN 10223-7 |
Companion Standards
ASTM A740 controls the geometry of welded wire mesh rolls. Companions frequently cited alongside it: ISO 565 / ASTM E11 (test-sieve aperture series), ISO 3310-1 (test sieves of metal wire cloth), ISO 4783 (selection of wire and aperture combinations), ISO 9044 (industrial woven wire cloth), and ISO 2941 (collapse/burst rating for finished filter elements).
When to Specify ASTM A740
ASTM A740 is the US-market reference; for metric programs pair it with the ISO designation so both markets read the order identically.
