Practical Summary of Key Techniques for Using SMT Dip Soldering Machines

Practical Summary of Key Techniques for Using SMT Dip Soldering Machines:

‌1. Precise Temperature Control‌

‌Preheating Settings‌

Turn on the machine 60 minutes in advance. For lead-free processes, strictly control the solder temperature at 260±5℃ (calibrate in real time using a temperature controller).‌

Maintain the preheating zone temperature between 80-150℃ for 40-100 seconds (to prevent thermal shock).‌

‌Solder Management‌

After immersing 4 boards, scrape off the oxide layer on the solder surface to prevent solder debris from being trapped in the joints.‌

When adding solder bars, ensure they are long enough to prevent them from being too short and tipping over bottom components.‌

‌2. Immersion Soldering Operation Techniques‌

‌Tin immersion technique‌

Immerse the PCB at a 5-10° angle slowly (an angle greater than 30° may cause solder splatter)‌

Immersion depth = 50%-70% of board thickness, with time strictly controlled at 3-5 seconds‌‌

‌Solder Joint Reinforcement‌

When lifting the board, maintain a 5-10° angle and rise at a constant speed to avoid solder joint deformation.‌

If the solder joint is incomplete, perform a secondary immersion (at a faster speed of within 2 seconds).‌

‌III. Quality and Safety Assurance‌

‌Pre-Soldering Protection‌

Apply flux to the copper foil side only; strictly prevent contamination of the component side.‌

Position the pins to avoid bottom components to prevent mechanical damage.‌

‌Post-soldering quality inspection‌

Visually inspect solder joints: reject incomplete soldering/short circuits/solder balls (focus on IC pins)‌

Isolate defective products with red labels and record them‌

‌4. Key precautions‌

‌Safety Operations‌

Maintain a distance of ≥30 cm from the solder tank; wear heat-resistant gloves when scraping solder residue‌

Immediately shut down and inspect the equipment if there is an abnormal temperature difference (temperature difference >5°C)‌

‌Equipment Maintenance‌

Clean solder residue and wipe the equipment surface with alcohol after shutting down each day‌

Rinse the flux spray system with alcohol weekly to prevent blockages‌

‌5. Efficiency-enhancing tips‌

Let the flux spray sit for 20 seconds before dipping to enhance activity.‌

Use magnetic fixtures for multi-batch production to reduce changeover time to 15 minutes.‌

By precisely controlling the tilt angle, temperature, and process transitions, yield can be improved by over 30%.‌