14L 20kHz Low-Frequency Sonication Bath – 0–600W Power Control for Sewage, Sludge & Industrial Parts

Frequency determines cavitation bubble size, impact force, and penetration depth. Lower frequencies produce violent impact for heavy dirt, while higher frequencies provide dense, gentle cleaning for sub-micron microstructures:

Based on Granbo multi-frequency switchable configurations (Single/Dual/Triple/Quad), we recommend:

To resist cavitation erosion, Granbo customizes tank thickness and welding based on operating frequency:

*Material Safety Tip: Soft metals (aluminum, brass, gold) and delicate glass/ceramics may scratch or fracture at 28kHz. We recommend 40kHz to 80kHz or pre-testing for delicate substrates.

When a workpiece has both stubborn contaminants and sub-micron precision requirements, use a multi-stage approach:

1. Stage 1 (Pre-cleaning / 28kHz or 40kHz): Strips heavy grease, rust, polishing paste, scale, or coarse metal particles.
2. Stage 2 (Fine Cleaning / 68kHz or 80kHz): Removes fine particles (5–10μm) from blind holes, threads, and complex internal geometry.
3. Stage 3 (Ultra-Precision Rinse / 120kHz or 200kHz): Eliminates sub-micron (<1μm) residues without damaging fragile surfaces or thin films.

• Sweep Mode: Automatically sweeps ±1kHz around the center frequency to eliminate standing waves, ensuring uniform cavitation across the bath.
• Degas Mode: Uses pulsed ultrasound intervals (e.g., 5s on / 5s off) to purge dissolved air/gas from liquids—crucial for HPLC sample prep and max cavitation efficiency.
• Pulse Mode: Rapidly cycles power from 100% to 0% to produce a "blasting" impact that removes tough or baked-on residues.

Granbo units utilize Full-Bridge Separately Excited PCB Driver Boards rather than cheap self-excited circuits:

1. Visualized Real-time Data: Displays live Power, Frequency, and Current for strict laboratory protocol logging.
2. High Power Density: Guarantees a standard ≥ 0.3W/cm² for thorough cleaning. Power Density = Ultrasonic Power (W) / Radiating Area (cm²)
3. Low Noise Operation: While 28kHz operation naturally produces more audible mechanical noise, Granbo's multi-layer noise-reduction design enables high-frequency units (≥68kHz) to operate at noise levels below 80dB.

Ultrasonic frequency determines sound wavelength and cavitation bubble collapse intensity:

• 20kHz (λ ≈ 72.5mm): Large bubbles, high collapse force. Best for heavy rust, sludge, and thick scale.
• 40kHz (λ ≈ 36.2mm): Medium bubbles. Ideal balance between cleaning power and component safety.
• 120kHz (λ ≈ 12.0mm): Micro bubbles. High penetration depth for sub-micron cracks and fragile silicon/semiconductor parts.

Beaker Size Matching:
• Beaker ≤ 500mL → 3.2L to 6.5L Tank.
• Beaker ≥ 800mL → 10L to 30L Tank (10L is the most popular size for general lab applications).

Temperature Management:
Ultrasonic activity inherently raises liquid temperature. Although Granbo heating goes up to 80°C, cavitation effectiveness drops significantly above 72°C–80°C due to increased vapor pressure. For temperature-sensitive or low-temp processes, use cooling coils or ice packs in the bath.

Standard production lead times for out-of-stock or customized Granbo models:

• 28kHz - 200kHz Models (Single, Dual, Triple, Quad Frequency): 3 - 5 business days for shipping.
• Ultra-Low Frequency (17kHz, 20kHz, 25kHz): 14 - 20 business days for shipping.

*Note: Customizations like RS-485 communication or PLC integration may slightly adjust delivery timelines. Contact us for precise scheduling.