After turning, milling, grinding and stamping, machined parts are contaminated with cutting fluid, processing oil, metal chips, polishing paste, anti‑rust oil and other residues. A properly selected ultrasonic cleaning machine can reliably remove contaminants while preventing corrosion and scratches on workpieces, and meet cleanliness requirements for subsequent electroplating, spraying and assembly. Key factors for equipment selection are as follows.

1. Select ultrasonic frequency according to workpiece material

• Hard workpieces such as carbon steel and alloy steel: 20‑28 kHz low frequency is preferred. It delivers strong cavitation impact for heavy‑duty removal of oil and metal chips. However, its high impact force may cause minor surface damage to soft materials.

• Aluminum alloy, copper and precision thin‑wall parts: Adopt medium‑high frequency of 40‑68 kHz. Its mild cavitation effect works well for parts with threads, blind holes and narrow gaps without attacking workpiece surfaces, ideal for high‑precision machined components.

Tip: Higher frequencies are used for more precise parts; lower frequencies suit heavily contaminated rough‑machined components.

2. Match tank dimension with production capacity

The inner tank size must exceed the maximum outer dimension of workpieces. Parts shall not rest directly on the ultrasonic transducer plate.

• Small‑batch production: Single‑tank model for trial runs and small‑volume cleaning.

• Mass production: Multi‑tank production line equipped with ultrasonic cleaning tank, rinsing tank, dehydration and drying tank to complete the full process of cleaning‑rinsing‑drying and avoid re‑contamination by oil residues.

Tank material: 304 / 316 stainless steel is recommended. 316 stainless steel offers superior corrosion resistance for aggressive cleaning agents.

3. Ultrasonic power configuration

Higher power does not always mean better performance. Insufficient power leads to poor cleaning results; excessive power causes cavitation erosion and pitting on workpiece surfaces.

General reference: 20‑40 W per liter of cleaning solution. Choose the higher end for heavy‑oil and complex‑structure parts, and the lower end for precision small parts. Power‑adjustable units are recommended to handle different batches of workpieces.

4. Essential auxiliary functions

1. Heating system: Most water‑based cleaning agents achieve optimal performance at 40‑60 °C; temperature‑controlled heating is standard.

2. Filtration and oil‑skimming system: Machining processes generate large amounts of oil and metal debris. Circulating filtration removes metal chips while oil skimmers separate floating oil, extending cleaning‑solution service life and cutting consumable costs.

3. Rinsing and drying: Ultrasonic cleaning alone is insufficient. Rinsing tanks are required to flush residual detergent; drying prevents rust on carbon‑steel parts after cleaning.

4. Transducer assembly: Removable immersion transducer plates are convenient for retrofitting existing tanks; built‑in welded transducer plates provide better sealing for standard equipment.

5. Compatibility between cleaning agent and equipment

Ultrasound provides physical cleaning force and must be used with appropriate water‑based cleaning agents. ‑ Steel parts: High‑alkaline water‑based degreasers. ‑ Non‑ferrous metals such as aluminum and copper: Neutral or mild‑alkaline special cleaners to avoid oxidation, discoloration and corrosion.

Verify that equipment materials are compatible with your selected cleaning agents before purchase.

6. Comprehensive evaluation based on working conditions

‑ For parts with blind holes, deep holes and threads: Medium‑high frequency is recommended to remove dirt inside cavities. ‑ Production mode: Single‑tank unit for laboratory‑scale small batches; automatic multi‑tank production line for mass‑volume manufacturing. ‑ High cleanliness requirements for downstream electroplating or spraying: Multi‑stage rinsing is suggested to minimize residual oil and chips.

Summary of selection logic: Determine frequency based on workpiece material and precision; define tank specifications according to part size and output; set power level by oil contamination severity; equip heating, filtration, rinsing and drying modules, and select compatible cleaning agents. This approach helps you identify the right ultrasonic cleaning machine for your application.