Gilson SS-20 / SS-20F Rotary Sifter with Sieve Stack Assembly

Overview

The Gilson SS-20 and SS-20F Rotary Sifters are precision-engineered laboratory instruments designed for standardized dry sieve analysis in accordance with ASTM E11, ISO 3310-1, and USP <786>. These units employ a dual-mode mechanical action—continuous rotary motion combined with controlled tapping—to achieve high reproducibility in particle size distribution measurements. Unlike vibratory or sonic sieving methods, the Gilson Rotary Sifter delivers consistent energy input across the entire sieve stack via two stainless steel drive rollers and an integrated UHMW polyethylene tapping hammer assembly. This architecture ensures uniform particle agitation while minimizing segregation bias and operator-induced variability. The instrument is purpose-built for QC laboratories, aggregate testing facilities, pharmaceutical R&D, and materials science applications where regulatory traceability, mechanical robustness, and long-term calibration stability are critical.

Key Features

• Dual-action separation mechanism: 360° continuous rotation + programmable tapping at fixed frequency and amplitude
• Ergonomic cabinet rotation system: Side-mounted knobs enable smooth 90° pivot between loading and test positions without clamping hardware
• Digital countdown timer with ±1-second accuracy: Adjustable range from 1 second to 99 minutes; pause/resume functionality preserves elapsed time
• Acoustically damped enclosure: MDF cabinet with powder-coated ASTM A513 structural frame reduces operational noise to <72 dB(A) at 1 m
• Modular sieve compatibility: Supports full-height (6 × 12″ or 10 × 8″) or half-height (20 × 8″ or 13 × 12″) stacks using standard ASTM/ISO frames
• UHMW-PE hammer head and 6061-T6 aluminum hammer assembly ensure wear resistance and inert contact with sensitive samples
• 1/4 HP continuous-duty motor with thermal overload protection; rated for 24/7 operation under nominal load conditions
• Large 0.5-inch (12.7 mm) LED display with high-contrast digits for ambient-lit or low-light lab environments

Sample Compatibility & Compliance

The SS-20/SS-20F accommodates dry, free-flowing granular materials within a nominal particle size range of 25 mm down to 20 µm (1 inch to No. 635 sieve). It is validated for use with all standard wire cloth, perforated plate, and electroformed mesh sieves conforming to ASTM E11 Class A tolerances and ISO 3310-1 specifications. The sealed cabinet design meets OSHA 1910.95 requirements for occupational noise exposure and contains airborne particulates during operation—critical for handling hazardous or potent compounds in GMP-compliant pharmaceutical labs. Units ship with full documentation supporting IQ/OQ protocols and are compatible with GLP audit trails when paired with Gilson’s optional SSA-76 controller logging module (time-stamped start/stop events, cycle count, voltage monitoring).

Software & Data Management

While the base unit operates via standalone digital controls, the SSA-76 Timer/Controller supports external data capture via RS-232 interface (optional cable SSA-76-COM). When integrated with LIMS or laboratory informatics platforms, it enables automated logging of test duration, motor status, and fault codes—including thermal cutoff events. Firmware supports user-defined presets for common test durations (e.g., 10 min per ASTM C136, 15 min per ISO 13320 Annex B), reducing manual entry errors. All timing parameters comply with FDA 21 CFR Part 11 requirements when used with electronic signature-enabled host systems. Calibration certificates include NIST-traceable timer verification and rotational speed validation at 25, 50, and 75 rpm.

Applications

• Aggregate gradation analysis per ASTM C136/C136M in civil engineering and asphalt QC labs
• Pharmaceutical blend uniformity assessment per USP <786> and ICH Q5C guidelines
• Cement fineness testing per ASTM C204 and EN 196-6
• Food ingredient particle sizing (e.g., flour, sugar, spices) under FDA 21 CFR 117 compliance
• Recycled material characterization (e.g., shredded rubber, plastic flakes) in environmental testing
• Research-scale catalyst support screening in chemical process development

FAQ

What sieve frame diameters and heights are supported?
The SS-20/SS-20F accepts standard 8-inch (203 mm) and 12-inch (305 mm) diameter frames in full-height, half-height, and intermediate configurations. Maximum stack height is 22 inches (559 mm) for full-height 12″ frames.
Is the tapping frequency adjustable?
No—the tapping mechanism operates at a fixed, factory-calibrated rate of 150 ± 5 taps per minute, optimized for ASTM E11 repeatability and validated across all sieve loading conditions.
Can the unit be integrated into a networked lab environment?
Yes—via optional RS-232 output (SSA-76-COM cable) and third-party SCADA/LIMS drivers. Time-stamped event logs include motor on/off, timer start/stop, and thermal fault triggers.
What maintenance is required for long-term accuracy?
Annual verification of rotational speed (±0.5% tolerance), timer accuracy (±1 sec/99 min), and hammer impact force (calibrated via Gilson Service Bulletin SB-SS20-03) is recommended. Drive roller surfaces should be inspected quarterly for wear.
Does the sifter meet CE or UKCA marking requirements?
The SS-20F (230 V / 50 Hz) model is CE-marked per EMC Directive 2014/30/EU and Low Voltage Directive 2014/35/EU. UKCA marking is available upon request with UK-based conformity assessment.