W.S. Tyler SS-31 Ro-Tap® Sieve Shaker

Overview

The W.S. Tyler SS-31 Ro-Tap® Sieve Shaker is a precision-engineered mechanical sieving instrument designed to perform standardized particle size distribution analysis in accordance with ASTM E11, ISO 3310-1, and USP <786>. It replicates the classic Ro-Tap® motion profile—combining horizontal circular oscillation (278 cycles/min) with vertical tapping (150 taps/min)—to ensure uniform particle stratification, efficient separation, and high reproducibility across repeated tests. Unlike vibratory or sonic shakers, the Ro-Tap® mechanism applies controlled mechanical energy that mimics manual sieving while eliminating operator variability. The SS-31 model accommodates up to four full-height 12-inch (305 mm) test sieves or eight half-height sieves in a single run, delivering over twice the effective screening area of 8-inch models. Its robust cast-iron base, reinforced steel frame, and ¼ HP induction motor support continuous operation under laboratory or quality control environments where regulatory compliance and long-term stability are critical.

Key Features

• Ro-Tap® dual-motion mechanism: 278 oscillations/min + 150 vertical taps/min for ASTM-compliant particle dispersion
• Dual-action motion ensures consistent particle orientation and minimizes blinding or agglomeration
• Adjustable sieve support plate with quick-release clamping for rapid setup of full-, half-, or intermediate-height sieve stacks
• Integrated digital timer with 0.1-second resolution and 99-minute maximum duration for precise test repeatability
• Sturdy bolt-down mounting capability for vibration isolation and stable operation on benchtops or dedicated platforms
• Compliant with NEMA 1 enclosure standards; designed for 24/7 duty cycle in QC labs and R&D facilities
• Motor-driven eccentric cam system engineered for minimal wear and maintenance-free performance over extended service life

Sample Compatibility & Compliance

The SS-31 supports standard 12-inch (305 mm) diameter test sieves per ASTM E11 and ISO 3310-1 specifications—including stainless steel, brass, and nylon mesh options—with opening sizes ranging from 12.5 mm (½ inch) down to 25 µm (No. 500). It accepts full-height, half-height, and intermediate-height sieve configurations, enabling flexible method development for coarse aggregates, pharmaceutical powders, catalysts, ceramics, and metal powders. All operational parameters—including tap frequency, oscillation amplitude, and timing accuracy—are traceable and verifiable per GLP/GMP requirements. When used with calibrated W.S. Tyler® certified sieves and paired with documented SOPs, the SS-31 meets audit readiness criteria for FDA 21 CFR Part 11–enabled workflows when integrated with compliant LIMS or ELN systems.

Software & Data Management

While the SS-31 operates as a standalone electromechanical unit without embedded firmware or network connectivity, its deterministic motion profile and precise timing enable seamless integration into validated digital workflows. Laboratories routinely pair the SS-31 with external data capture tools—including balance interfaces, barcode scanners, and electronic lab notebooks—to log sieve stack configuration, run duration, ambient conditions, and mass retention per fraction. For regulated environments, time-stamped operation logs can be generated via external programmable logic controllers (PLCs) or industrial timers with audit-trail functionality. Optional accessories such as Clean-N-STOR fraction collectors and sound-dampening enclosures further enhance process control and documentation integrity during routine testing.

Applications

• Quality assurance of bulk pharmaceutical excipients and active ingredients per USP <786> and Ph. Eur. 2.9.33
• Particle size analysis of construction aggregates, mineral ores, and foundry sands per ASTM C136 and AASHTO T 27
• Characterization of battery electrode materials, catalyst substrates, and additive manufacturing powders
• Validation of milling and micronization processes in chemical and food processing industries
• Research-grade granulometric profiling for geotechnical soil classification and environmental sediment analysis
• Calibration verification of laser diffraction or dynamic image analysis instruments using reference standards

FAQ

What sieve diameters and heights does the SS-31 support?
The SS-31 accommodates 12-inch (305 mm) diameter sieves in full-height, half-height, and intermediate-height configurations—up to four full-height sieves or eight half-height sieves per run.
Is the SS-31 compatible with ISO-standard sieves?
Yes—it accepts ISO 3310-1–compliant 305 mm sieves, including those with metric aperture designations (e.g., 12.5 mm to 25 µm), provided frame height and clamping geometry match W.S. Tyler® specifications.
Can the SS-31 be integrated into a 21 CFR Part 11–compliant environment?
As a Class I electromechanical device, the SS-31 itself does not store or transmit data; however, its repeatable, timer-controlled operation supports Part 11 compliance when paired with validated external data capture systems and procedural controls.
What voltage and frequency options are available for the SS-31?
Three variants are offered: SS-31 (115 V / 60 Hz), SS-31F (230 V / 50 Hz), and SS-31S (230 V / 60 Hz), each rated at 2.2–4.4 A depending on input configuration.
Does the SS-31 require periodic calibration?
While no internal calibration is required, users must verify tap frequency, oscillation rate, and timer accuracy annually using NIST-traceable instrumentation per ASTM D6913 and ISO/IEC 17025 guidelines.