ASTM Specification E161-12 covers the requirements for design and construction of electroformed sieves. These sieves are used to perform particle size distribution analysis, and in preparing narrowly designated particle-size fractions. They may also be used as reference standards when suitably calibrated.
The material used in the manufacture of the sieve sheet is nickel or a metal suitable for electrode position in a firm crystalline structure. The sheet shall have square or round openings with straight uniform sides and smooth, flat surfaces except for a slight bevel along the edges of the openings.
Frames for precision electroformed sieves shall be made from non-corrosive material such as brass or stainless steel, and constructed in such a manner as to be rigid.
As seen for this description an electroformed sieve presents a precise aperture that is uniform across the media. They are use for high-level quality assurance and for very small particles down to 4 microns.
The process of electroforming the sieve mesh results in very tight tolerances of the openings. It is possible to build sieves using this process that can hold a +/- 2 micron tolerance.
We offer a wide range of aperture sizes in either 3 inch or 8 inch diameter.