Precise test sieve cleaning in an ultrasonic bath: Maximum reproducibility for particle size analysis
What does an ultrasonic bath deliver in industrial quality assurance?
The key question often asked by laboratory managers and testing specialists is: what does an ultrasonic bath offer compared to conventional cleaning methods? The answer lies in the physics of cavitation. An ultrasonic bath converts electrical energy into high-frequency sound waves, which are transmitted through a cleaning liquid. In NEXOPART ultrasonic Cleaning Devices, the ultrasonic transducers typically operate at a frequency of 35 to 37 kHz.
These high-frequency vibrations generate microscopic vacuum bubbles in the liquid. When these bubbles implode on the surface of the item being cleaned, extreme localized pressure and temperature peaks occur, along with microcurrents. This physical effect “blasts” even the most stubborn contaminants and trapped particles precisely out of the finest sieve meshes without placing mechanical stress on the material.
The advantage in industrial applications is clear: cleaning of Test Sieves is extremely gentle and highly effective at the same time. The mesh tension and the precise mesh sizes of the Test Sieves remain fully intact. In addition, a high-performance ultrasonic bath enables cleaning of hard-to-reach areas such as the transition between sieve frame and mesh. The risk of cross-contamination in subsequent sieve analysis is reduced to a minimum. At the same time, the time required for laboratory personnel decreases significantly, as the devices operate largely autonomously.
The NEXOPART USC series:
Tailored ultrasonic solutions for every sieve size
To meet a wide range of requirements—from research to heavy industry—NEXOPART offers customized ultrasonic Cleaning Devices that are precisely matched to the dimensions of standardized Test Sieves. The housings and tanks are made of robust, durable stainless steel, ensuring high corrosion resistance and easy maintenance.
NEXOPART USC 200 S: Compact. Precise. Reliable.
The USC 200 S model is designed for cleaning a single Test Sieve up to a Diameter of 230 mm. With a total volume of 6 liters (recommended working volume 3.0 to 5.0 liters) and compact external dimensions, this device is ideal for laboratories with moderate throughput.
- Tank (internal dimensions): Ø 240 × 140 mm
- Ultrasonic frequency: 37 kHz
- Power: 150 watts effective ultrasonic power (600 watts peak power)
- Accessories: Includes a suitable sieve holder for laboratory Test Sieves (100 mm and 200 mm), enabling optimal positioning in the liquid
NEXOPART USC 500 S: Power meets size.
For users working with large sample volumes and corresponding Test Sieves—such as in the construction materials or bulk solids industry—the USC 500 S is the right choice. It accommodates sieves up to a Diameter of 500 mm.
- Tank (internal dimensions): Ø 600 × 245 mm
- Volume: 69 liters total volume (59 liters recommended working volume)
- Power: 650 watts effective ultrasonic power (up to 2600 watts peak power)
- Equipment: Features an integrated ball valve (1/2 inch connection thread) for safe and ergonomic draining of large liquid volumes
NEXOPART USC 200 Multi: Maximum throughput for serial sieve analysis
When time pressure and a high number of daily tests define laboratory work, the USC 200 Multi shows its strengths. This industrial ultrasonic bath allows up to five Test Sieves (up to 230 mm Diameter) to be cleaned simultaneously.
- Tank (internal dimensions): 500 × 300 × 300 mm
- Volume: 40 liters
- Ultrasonic frequency: 35 kHz
- Power: 500 watts effective (2000 watts peak power)
- Advantage: Significant time savings when processing large series of samples
Intelligent operating modes for specific cleaning requirements
A key quality feature of NEXOPART devices is the integrated control system, which allows the ultrasonic field to be adjusted to the specific laboratory task. This ensures effective cleaning while protecting the instrument. Four specific ultrasonic modes are available via the control panel:
- Sieve cleaning (pulse mode): Generates a pulsating sound field. Power peaks release even extremely stubborn particles trapped in the wire mesh.
- Degas mode (including auto-degas): Fresh water contains dissolved gases and air bubbles that dampen the ultrasonic effect and significantly reduce cleaning performance. Degas mode removes these gases. The auto-degas function runs automatically for about 10 minutes before switching to normal cleaning operation.
- General cleaning (sweep mode): Provides particularly uniform sound distribution throughout the tank. Used for general ultrasonic cleaning of instruments or laboratory vessels to avoid dead zones.
- Sample preparation (dynamic mode): A mode for sample preparation. Delivers higher power, ideal for mixing, dissolving, or dispersing substances (e.g., rapid degassing of HPLC solvents).
Additionally, the devices feature precise time control. Cleaning time can be programmed in stages up to 30 minutes. Alternatively, continuous operation (ON) allows running times of up to 6 hours before an automatic safety shutdown engages.
Frequently asked questions about ultrasonic cleaning baths
What can—and cannot—be cleaned in an ultrasonic bath?
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What must not be cleaned in an ultrasonic bath?
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Practical guide: Step by step to standard-compliant sieve cleaning
To ensure reproducibility of sieve analysis and maximize the service life of equipment, cleaning should follow a defined SOP (Standard Operating Procedure):
- Preparation and filling: Place the device on a non-slip, water-resistant surface. Fill the tank with water up to the level mark. For large models (USC 500 S and Multi), check the drain valve for leaks and ensure it is securely closed.
- Dosing of cleaning agent: Dose the NEXOPART USC cleaning fluid (1 to 5% by volume) according to the volume table and mix gently.
- Degassing the liquid: Before inserting the sieves, switch on the device and activate degas mode for about 10 minutes. Removing gases is essential for full cavitation performance in the subsequent process.
- Inserting the items: The mesh must be fully immersed in the cleaning liquid. Carefully place the basket into the tank without touching the bottom. Position the Test Sieves in the dedicated sieve holder (included with USC 200 S) or in the stainless steel immersion basket.
- Start ultrasonic cleaning: Cover the device with the plastic or stainless steel lid (protection against vapors and sound emissions; sound pressure level below 80 dB). Select sieve cleaning (pulse mode) for sieves and set the timer to typically 3 to 10 minutes depending on contamination.
- Removal and post-treatment: After automatic stop (acoustic signal), remove the basket. The sieve must be thoroughly rinsed with clean water to remove all loosened particles and cleaning agent residues. Then dry the sieve gently, ideally at temperatures below 80 °C, to prevent heat-related changes in mesh tension.
By establishing this standardized process with an industrial ultrasonic bath, each Test Sieve reliably meets ISO standard requirements. The combination of the mechanical precision of NEXOPART Test Sieves and the material-friendly processing in an ultrasonic Cleaning Device forms the foundation for uncompromising accuracy in quality assurance.