Factors to Be Considered When Formulating a Cleaning Solution for Precision Stamped Parts

1. Workpiece‑related Properties

1. Material: Stainless steel, copper, aluminum, zinc alloy, plated components. Copper and aluminum are prone to oxidation and darkening; plated parts must avoid highly corrosive cleaning agents; water‑spot and white‑mark issues shall be controlled for stainless‑steel parts.

2. Structure & Shape: Thin sheets, thin‑wall parts, deep grooves, folded corners, interlayers, micro‑holes. High‑intensity ultrasonic energy that may cause deformation of thin‑wall workpieces shall be avoided; vacuum‑penetration processes are recommended for grooves and interlayers prone to dirt trapping.

3. Size & Batch Form: Drum‑type cleaning is preferred for large‑volume micro‑parts which are easy to stack and scratch; continuous production lines are suitable for large‑sized parts or single‑item mass production; flexible equipment is recommended for multi‑variety and small‑batch production.

2. Type and Level of Contamination

‑ Oil contaminants: Stamping‑drawing oil, cutting oil, rust‑preventive oil, heavy stamping grease. Cleaning solutions differ greatly between heavy‑oil and light‑oil conditions. ‑ Solid impurities: Fine metal chips, stamping dust, burr residues, polishing wax. Solvent‑based cleaning is generally required for wax removal. ‑ Additional stains: Fingerprint residues, coolant contaminants.

3. Cleanliness Requirements

1. Visual standards: Free of water spots, watermarks, white specks, discoloration, scratches and luster loss.

2. Particle cleanliness: Compliance with automotive particle inspection standards such as VDA‑19 and ISO16232; clean‑room assembly requirements for 3C‑electronics and new‑energy components.

3. Downstream processes: Subsequent operations including direct assembly, electroplating, coating and welding impose different limits on ion residues and cleanliness grades.

4. Selection of Cleaning Processes

1. Cleaning medium options: Hydrocarbon solvent, modified‑alcohol solvent, water‑based detergent.

2. Cleaning methods: Ultrasonic cleaning, spraying, jet flushing, drum tumbling, immersion. 28/40/80 kHz ultrasonic frequencies are available; high‑frequency ultrasound is preferred for thin sheets.

3. Drying methods: Vacuum drying (high‑end, zero water‑mark), hot‑air drying, air‑knife dehydration.

5. On‑site Production Conditions

1. Production cycle: Workpiece throughput per hour determines whether a standalone machine or a fully‑automatic production line is required.

2. Workshop utilities: Availability of purified‑water supply, wastewater treatment, explosion‑proof ventilation (for solvent‑based equipment).

3. Floor space & automation level: Compatibility with robotic loading/unloading and production‑line integration.

6. Cost & Long‑term Operation

Equipment procurement cost, consumable expenses for detergent/solvent, energy consumption, maintenance difficulty, labor cost and solvent recovery rate.

7. Safety, Environmental Protection & Compliance

Waste‑water discharge control, VOC emission regulation, explosion‑proof safety of solvent equipment and local environmental‑protection regulations.

8. Yield‑risk Control

Risks including collision scratches, deformation, oxidation and discoloration of workpieces. Small‑batch trial cleaning verification is required before finalizing the solution.