Manual Geotextile Apparent Opening Size (AOS) Tester - QualiGTX™ AOS M
QualiGTX™ AOS M geotextile apparent opening size tester measures the characteristic pore size of single-layer geotextiles and related geosynthetic products by the dry sieving method. Manual controls drive a motorized sieve shaker, which gives laboratories a direct route to O95 data without a programmable interface to configure or maintain. The unit accepts woven, nonwoven, and composite fabrics across the full range of commercial geotextile constructions. Quality-control teams, contractors, and certification labs use the result to match a fabric to the soil it has to retain.
Each cycle takes five specimens at once. Five pressing rings hold the fabrics flat inside the sieve column, and five stainless steel sieve pans catch the beads that pass through each specimen. A graded glass bead set ships with the instrument. The 200 mm sieve column stacks to 400 mm, leaving room for a full set of frames and pans in one run. That arrangement turns a five-fabric batch into a single test instead of five sequential ones.
Agitation values come with published tolerance bands rather than single nominal figures. The sieve base oscillates at 220 cycles per minute plus or minus 10, taps at 150 impacts per minute plus or minus 10, and works through a 10 mm amplitude with a 12 mm radius of gyration. Those bands let a laboratory verify the machine against its governing method at commissioning and during periodic checks. At 80 kg, the frame stays compact enough for a standard laboratory footprint.
