W.S. Tyler SS-31 Ro-Tap® Sieve Shaker
| Origin | USA |
|---|---|
| Manufacturer Type | Authorized Distributor |
| Origin Category | Imported |
| Model | SS-31 |
| Pricing | Upon Request |
Overview
The W.S. Tyler SS-31 Ro-Tap® Sieve Shaker is a precision-engineered mechanical sieve shaker 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—278 horizontal circular oscillations and 150 vertical taps per minute—ensuring high reproducibility across repeated tests. Unlike orbital or vibratory shakers, the Ro-Tap® mechanism combines planar circular motion with synchronized vertical impact, generating consistent energy transfer to the sieve stack for reliable stratification and separation of dry granular materials. The SS-31 accommodates up to four full-height 12-inch (305 mm) test sieves or eight half-height sieves, delivering over twice the effective screening area of its 8-inch counterpart (SS-30), making it particularly suited for low-yield, fine-particle applications where statistical representativeness and throughput efficiency are critical.
Key Features
- Robust 1/4 HP induction motor with thermal overload protection, engineered for continuous-duty laboratory and QC environments
- Digital timer with 0.1-second resolution and programmable range up to 99 minutes, supporting GLP-compliant test documentation
- Adjustable sieve clamp assembly enabling rapid, tool-free height calibration for full-, half-, and intermediate-height sieve stacks
- Stabilized base design compatible with bolt-down mounting to concrete or steel workbenches to minimize operational vibration transmission
- Integrated tap amplitude control ensures consistent kinetic energy delivery regardless of stack mass or sieve mesh configuration
- Compliance-ready construction: All electrical components meet UL 61010-1 and CE standards for laboratory equipment safety
Sample Compatibility & Compliance
The SS-31 supports dry, free-flowing powders and granules across a broad particle size range—from 0.5 inch (12.5 mm) down to No. 500 (25 µm)—with optimal performance between No. 20 and No. 325. It accepts standard 12-inch (305 mm) diameter test sieves conforming to ASTM E11 (woven wire cloth) and ISO 3310-1 (stainless steel or brass). Full-height sieve stacks may include retention pans, receiver pans, and intermediate support plates. The unit is routinely validated in pharmaceutical, mineral processing, and cement manufacturing labs under FDA 21 CFR Part 11–aligned workflows, where audit trails, user access control, and instrument calibration records are maintained per internal SOPs.
Software & Data Management
While the SS-31 operates as a standalone electromechanical device without embedded firmware or network connectivity, its deterministic motion profile and precise timing enable seamless integration into LIMS and ELN ecosystems via external data capture. Users commonly pair the shaker with digital balance interfaces and automated sieve weighing stations that log timestamped mass data per sieve fraction. Optional accessories—including the Clean-N-STOR fraction collector—support traceable, contamination-minimized handling of separated fractions. For regulated environments, documented IQ/OQ protocols are available from W.S. Tyler’s authorized service partners, including verification of tap frequency (±1.5%), oscillation amplitude (±0.5 mm), and timer accuracy (±0.1 s over 60 min).
Applications
- Quality control of raw materials in pharmaceutical solid dosage manufacturing (e.g., lactose, microcrystalline cellulose)
- Particle size grading of industrial catalysts, pigments, and ceramic powders prior to sintering
- Aggregate classification in construction materials testing per ASTM C136 and AASHTO T 27
- Mineral liberation analysis in metallurgical process development
- Validation of milling and micronization processes across R&D and production scales
- Environmental sediment analysis in regulatory compliance testing (e.g., EPA Method 1695)
FAQ
What sieve standards does the SS-31 support?
It accepts all 12-inch (305 mm) diameter test sieves compliant with ASTM E11, ISO 3310-1, and EN 933-1, including stainless steel, brass, and phosphor bronze woven wire cloth.
Can the SS-31 be used with ISO-standard 200 mm sieves?
No—the SS-31 is dimensionally configured exclusively for 12-inch (305 mm) frames. For 200 mm sieves, the SS-30 or SS-33 models are recommended.
Is the tap frequency adjustable?
No—the Ro-Tap® motion profile is mechanically fixed at 278 oscillations and 150 taps per minute to ensure strict adherence to ASTM-defined test conditions.
Does the SS-31 require periodic calibration?
Yes—annual verification of timer accuracy, tap count consistency, and motor speed stability is recommended per ISO/IEC 17025 and internal quality system requirements.
Can multiple SS-31 units be synchronized for parallel testing?
Not natively; however, external PLC-based timing controllers can coordinate start/stop signals across multiple units when deployed in high-throughput QC laboratories.
