Test Sieves are available in a variety of configurations suited to different particle-sizing applications. Most are configured to meet particular requirements of various ASTM or ISO specifications, and are designed to stack, or nest, with others of similar construction for efficient, sequential separations. “Conventional” test sieves have round metal frames of stainless steel or brass with mesh woven from stainless steel or brass wire.
ASTM E11 or ISO 565/3310-1 specifications govern the majority of particle sizing procedures, and have become more closely harmonized with each other in recent years to simplify international use. Test Sieves following these ASTM or ISO standards are supplied as standard Compliance Grade, and are serial numbered and supplied with a certificate of manufacturing conformance. Compliance Grade sieves can be upgraded to Inspection or Calibration Grades by adding the appropriate Gilson Verification Service to your order.
Wet-Washing test sieves feature specially constructed extra-deep frames to allow accurate and efficient testing of some difficult materials by wet-sieving techniques. Wet-washing is typically performed on one sieve at a time, agitating the material in the sieve under a flowing or sprayed stream of water as fines are washed away. Some sieve shakers can be set up to allow the water to flow through an entire stack of sieves, with separation assisted by the mechanical agitation of the shaker.
Sonic sifters rapidly oscillate the column of air enclosed by the sieve stack to agitate specimen particles. This equipment is best for small samples of fine powders. AutoSiever sieves are available fitted with either woven-wire or precision electroformed cloth. Our 3” acrylic frame test sieves are specially designed to fit the Gilsonic AutoSiever.
Air Jet sieves are supplied to fit popular Air Jet Siever models. These sievers use positive air pressure flowing through a rotating nozzle to fluidize the specimen on the sieve. An external vacuum creates negative pressure to draw the finer material through one sieve at a time into a separate container. Air Jet Sieves feature a frame with a recess for a closely fitting lid, and a built-in sealing gasket to fit the siever housing.
Precision Electroformed test sieves are ideal for testing of fine powders and granular materials, where accuracy is critical. The mesh used in Precision Electroformed sieves is formed by electro-deposition of metal on a very precise grid of square openings. Electroformed sieves have 8in or 3in frames and extremely accurate mesh openings in sizes as small as 5µm. They comply with ASTM E161 and ISO 565/3310-3 requirements.
8in diameter two-part sieve frames constructed in either polycarbonate or brass have replaceable non-metallic cloth that is easily removed and discarded after use. The sieve cloth is made of monofilament polyester or nylon and is ideal for materials that are sensitive, hazardous, or when cross-contamination is a concern. Non-metallic cloth has accurate and consistent openings in sizes similar to ASTM and ISO openings, but does not strictly comply with those standards.
3in diameter non-metallic test sieves with polyester mesh are useful for wet sieving of small samples. have clear polycarbonate frames and polyester mesh. These hand-made sieves are useful for wet sieving of small samples. The clear polycarbonate frames allow easy viewing of wet sieving operations, and the polyolefin band covering the frame joint makes an effective seal when stacking multiple sieves. The sieves are autoclaveable and microwaveable for drying.