In the field of electronics manufacturing, the widespread use of lead-free solder paste has brought environmental improvements, but also created new cleaning challenges. When dealing with lead-free solder paste waste, traditional solvent-based cleaning agents not only face material compatibility risks (such as nickel/silver plating corrosion) but also face compliance pressure due to excessive VOC emissions. The water-based pneumatic cleaning technology equipped on Dezheng Intelligent’s DEZ-C730 pneumatic stencil cleaning machine has redefined the treatment standards for lead-free solder paste waste through three fundamental breakthroughs.
1. High-pressure pneumatic jet: micron-level cleaning force penetrates residual barriers
The rosin and thixotropic agent in lead-free solder paste easily form micropore residues of less than 0.1 mm after reflow soldering. The cleaning effect of traditional ultrasonic cleaning on thick stencils (>2.5 mm) is less than 30%. DEZ-C730 stencil cleaning machine uses a high-density, double-sided isobaric 360° rotating nozzle and achieves the following improvements through pneumatically driven high-pressure water flow (0.5-0.7 MPa):
- Dynamic Impact Cleaning: The rotating nozzle sprays at a speed of 2,000 rpm, generating a water flow impact force of 20 m/s, which directly eliminates the molecular-level adhesion between the solder paste and the steel mesh surface.
- Micro-gap penetration: Combined with the low surface tension of water-based cleaning agents (<30 mN/m), the cleaning solution can penetrate deep into the 0.02 mm ultra-fine mesh and completely remove residue from the bottom.
- Zero-damage design: Driven by a pneumatic motor to prevent potential electrostatic damage to electrical equipment, a pressure sensor is used to adjust the spray force in real time to ensure stable tension of the steel mesh.
Data verification: An automotive electronics factory used our DEZ-C730 pneumatic stencil cleaning machine to clean QFP steel mesh with a 0.3 mm pitch. The residue was reduced from 12.6 mg/cm² by manual cleaning to 0.8 mg/cm², meeting the IPC-7526 Class 3 standard.
2.Three-Stage Filtration System: Recycling Technology Overcomes the Cost Bottleneck
In traditional cleaning processes, solvent consumption accounts for 45% of stencil maintenance costs, but the DEZ-C730 pneumatic stencil cleaner’s three-stage filtration system achieves efficient circulation thanks to the following innovations:
- Physical Interception: The 10 μm primary filter screen filters out solder balls and label residue to prevent large particles from clogging the nozzle.
- Fine Separation: The 5 μm screen filter intercepts silver paste and ink impurities, ensuring the cleaning fluid’s cleanliness remains at over 98%.
- Nano-Level Purification: 1 μm depth filtration removes colloid and resin residue, extending the cleaning fluid’s lifespan to 5 times that of traditional processes.
Economic benefits: After a certain factory adopted our DEZ-C730 pneumatic stencil cleaning machine, annual cleaning agent consumption was reduced from 1200L to 240L. Combined with the closed-loop recycling system, the annual cost savings for a single device exceeded 150,000 yuan.
3.Fully pneumatic and environmentally friendly design: double guarantee of safety and compliance
In response to the strict environmental requirements for lead-free solder paste cleaning, the DEZ-C730 pneumatic steel mesh cleaning machine achieves a balance between safety and efficiency through the following designs:
- Non-electric operation: It relies entirely on compressed air, eliminating fire risks and is especially suitable for explosion-proof workshops.
- Low volatile emissions: The S-type exhaust pipe and activated carbon adsorption device control VOC emissions to below 50 ppm, in compliance with EU REACH regulations.
- Human-machine isolation: The one-button operation interface and fully enclosed cleaning booth prevent operators from coming into contact with cleaning agents and reduce the risk of occupational diseases.
Industrial Application: A medical device manufacturer uses our DEZ-C730 pneumatic steel mesh cleaning machine to clean the steel mesh of an implantable circuit board. After cleaning, the residual ion content on the board surface is <0.5 μg/cm², meeting ISO 10993 biocompatibility certification.
Technology Trends and Selection Suggestions
- Material Compatibility: Water-based cleaning agents with a neutral pH (such as ZESTRON VIGON® A 200) are preferred to prevent corrosion of aluminum/copper substrates by alkaline cleaning agents.
- Process Adaptation: For red glue and thick stencils, pneumatic spray technology (such as Silman tech DEZ-C 740) can be used to improve cleaning depth.
- Intelligent Upgrade: Combined with an AI visual inspection system (such as Sanjie Machinery’s intelligent equipment), real-time traceability of the cleaning effect can be achieved.
The three major advancements of the DEZ-C730 not only solve the technical problem of lead-free solder paste residue, but also provide electronics manufacturers with sustainable solutions that meet ESG requirements through eco-friendly design and cost optimization.
