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Selecting a Stencil Cleaning Process

Selecting a Stencil Cleaning Process. - Chemistry - Cleaning Machine - Waste Management www.electronics-trading.com. Goal and Objectives. Obtain an environmentally safe, user safe and flexible stencil cleaning process Must be cost effective (start-up and operational)

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Selecting a Stencil Cleaning Process

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  1. Selecting a Stencil Cleaning Process - Chemistry - Cleaning Machine - Waste Management www.electronics-trading.com Smart Sonic

  2. Goal and Objectives • Obtain an environmentally safe, user safe and flexible stencil cleaning process • Must be cost effective (start-up and operational) • Must cleanfine-pitch • Must clean current and potential future solder pastes • Must meet current and future environmental regulations • Must not pose any user health or safety issues • Must not damage stencils • Possibly clean other applications (adhesives, flux residues) Smart Sonic

  3. Limiting Factors • Heat Sensitivity • Stencils are heat sensitive. Hot water or hot drying air can breakdown the glue, bonding the screen to the frame and metal etched foil. Heat can also cause distortion of fine-pitch apertures due to expansion & contraction of metals • Fine-pitch Applications • Cleaning Applications • Solder paste, SMD adhesives, flux residue from pallets or radiators, etc. • Environmental Regulations • Will Flux Types or Pitch Size Change in Future? Smart Sonic

  4. Where To Start • Select the Chemistry first! • The most important factor of any cleaning process is always the Chemistry • The chemistry determines the: • Reaction with the contaminant • Environmental impact • User safety – health, fire, explosion potential • Operational cost of the process • Presents of odors & vapors (hot water vapor contamination) • Cleaning cycle time • Process flexibility to clean different solder pastes • Requirement for heat (stencil damage, energy use) • Maintenance requirements • Storage and transportation requirements • Waste management Smart Sonic

  5. Where To Start • The Cleaning Machine only determines the: • Initial capital cost • Footprint • Mechanical scrubbing action and it’s ability to deliver chemistry inside fine-pitch apertures • User interface and process simplicity • Potential to damage stencil (high pressure sprays, heat, etc • Ease of maintenance Smart Sonic

  6. Where To Start • Waste Management determines the: • Permit requirements • Long term liability • Documentation requirements (manifestation) • Quantity solids vs. liquids • Cost of disposal Smart Sonic

  7. Today’s Choices • CHEMISTRY • Solvents • Semi-aqueous • Aqueous (plain water, saponifiers, detergents) • CLEANING MACHINE • Hand clean • Spray in air • Spray under immersion • Ultrasonics • WASTE MANAGEMENT • Haul away • Filter • Evaporate Smart Sonic

  8. Today’s Choice of Chemistries • Solvents • Advantages • Clean without heat • Usually dry fast • Some are cheap (alcohol, acetone, etc.) • Disadvantages • Environmentally problematic • Pose health and safety hazards (cancer, fetus, fire, explosion) • Do not clean all types of solder paste • Long term disposal liability • Odors in workspace • Special storage & transportation • Special permit requirements • Some are costly Smart Sonic

  9. Today’s Choice of Chemistries • Semi-aqueous • Advantages • Can be closed-looped • Clean without heat • Disadvantages • Environmentally problematic • Requires water rinse (two waste streams) • Requires special equipment • Usually expensive • Do not clean all types of solder paste • Requires special permits • Odors in workspace • Requires dry cycle Smart Sonic

  10. Today’s Choice of Chemistries • Aqueous - plain water • Advantages • Cheap • One waste stream • Can use spray or ultrasonic equipment • Waste water can be evaporated • Disadvantages • Cleans only water soluble solder paste • Requires dry cycle • Not flexible • May require heat Smart Sonic

  11. Today’s Choice of Chemistries • Aqueous – Saponifiers • Advantages • Same chemistry used to clean PCBs • Disadvantages • Caustic • Require heat that will damage stencils • Contain hazardous ingredients that prohibit evaporation of wastewater • Consumed during cleaning process • High cost of operation • Hot water vapor can contaminate assembly area • Pose safety hazard to user • High pH will (13+) will oxidize aluminum frame • Odor in workspace Smart Sonic

  12. Today’s Choice of Chemistries • Aqueous – Detergents • Advantages • Flexible - Clean many types of solder pastes • Can clean without heat • Can be environmentally safe • Can be user safe • Surfactant (wetting agent) is not consumed in cleaning process • Inexpensive • Wastewater qualifies for evaporation or filtration • Some can also clean adhesives and flux residues • Field tested effective for over 10 years • Disadvantages • Requires dry cycle www.electronics-trading.comsmt@electronics-trading.com Smart Sonic

  13. Today’s Choice of Machines • Spray in Air & Spray Under Immersion Systems • Advantages • Able to use aqueous, semi-aqueous or solvent chemistry with certain modifications • Usually simple operation • Disadvantages • Cannot spray into fine-pitch apertures effectively • High pressure sprays can bend delicate land mass areas • Cannot clean vias of misprinted PCBs • Cannot clean double sided misprinted PCBs because of solder ball contamination of side A • Requires clumsy fixturing of stencil • Requires internal filtration system • Will only clean as well as the chemistry used in it Smart Sonic

  14. Today’s Choice of Machines • Ultrasonics • Advantages • Microscopically cleans fine-pitch apertures • Will not cause bends in delicate land mass areas • Simple operation • Filtration system usually not required • Cycle time can be fast with right chemistry • Low maintenance • Inexpensive manual machines clean just as well as more expensive automated systems • Disadvantages • Will only clean as well as the chemistry used in it Smart Sonic

  15. Waste Management Systems • Haul Away by Others • Advantages • Easy • Disadvantages • Long term liability put on user (User responsible for mishandling and/or accidents of waste hauler-Super Fund) • High and continued cost Smart Sonic

  16. Waste Management Systems • Filtration • Advantages • Inexpensive micron filtration for water washable solder paste • Easy maintenance • Disadvantages • Expensive ion exchange or reverse osmosis systems required for no-clean, RMA and synthetic solder pastes • Always an effluent left for drain disposal which exposes user to potential liabilities of drain contamination (Super fund laws) • Continued cost of replacement filters • Not 100% effective Smart Sonic

  17. Waste Management Systems • Evaporation • Advantages • Inexpensive – Capital cost is usually less than ion exchange or reverse osmosis filtration systems • Low operating cost – No replacement filters. Low energy consumption • 100% effective • No liquid hazardous waste for disposal • Nothing goes to drain • Disadvantages • Maintenance is difficult for some models. However, maintenance cycles are usually infrequent • Requires ventilation or outdoor placement Smart Sonic

  18. Best Total Process • Aqueous Detergent Chemistry • Ultrasonic Cleaning Machine • Evaporation Waste Management Smart Sonic

  19. The Smart Sonic Stencil Cleaning Process • 440-R SMT Detergent • The only chemistry Certified Environmentally Safe and User Safe by the Environmental Protection Agency • Guaranteed to cleans all types of solder paste • Cleans at ambient temperature. No heat to damage stencils and no waste of energy to heat wash solutions • Not consumed during the cleaning process. A fixed amount is used between maintenance cycles. 5 Gallons (20 liters - less than $90) per month for Model 1500 and 2000 Stencil Cleaners • No special storage or transport requirements • Cleans SMD adhesives and post solder flux residues • Field tested for over 10 years by over 700 installations • SMT Vision Award Winner • Mild pleasant odor • Cost effective Smart Sonic

  20. Smart Sonic Stencil Cleaning Process • Ultrasonic Cleaning Machines • Model 1500 – Semiautomatic • Lowest priced ultrasonic stencil cleaner • Cleans 29” (750mm) stencils in less than 2 minutes • Can clean solder paste, adhesives and/or flux residues • Small footprint, ergonomically designed for easy loading • Models 2000 and 2003 - Semiautomatic • Similar to the Model 1500 with a few more bells and whistles • The Model 2003 has one heated wash tank and one ambient • Model 5000 Fully Automatic System • Wash, rinse and optional dry at the touch of one button • Cleans 29” stencils in less than 2 minutes (excludes drying) • Fully programmable • Easy to load and unload Smart Sonic

  21. Smart SonicStencil Cleaning Process • Waste Management System - Evaporators While the smart sonic waste water may be filtered like other aqueous wastewaters, the Smart Sonic wastewater qualifies for routine liquid evaporation. Most users see significant advantages to evaporation over filtration. • Model SE-1 – Standard Evaporator with standard cleanout and maintenance features commonly used throughout industry • Model EZ-0 – Easy maintenance and easy cleanout makes this a popular system. Smart Sonic designed this system for unique compatibility with the Smart Sonic Stencil Cleaners Either evaporator can be used with any Smart Sonic Stencil Cleaner Smart Sonic

  22. How Did We Get Here? • Smart Sonic introduced the industry’s first Ultrasonic Stencil Cleaner in 1990 to take advantage of our unique 440-R SMT Detergent. Since 1990, the Smart Sonic Stencil Cleaning Process has: • Satisfied the stencil cleaning requirements of over 700 SMT assemblers worldwide. • Been Certified Environmentally Safe and User Safe by the Environmental Protection Agency (EPA). • Been evaluated by industry experts and awarded top honors by the SMT Vision Award (twice), the NEPCON West Kiver Award, the Canadian High Technology Award, Certified by the California EPA and Verified Environmentally Safe and Effective by the U.S. EPA. • Smart Sonic has more experience with Ultrasonic Stencil Cleaning than all other manufacturers combined! Smart Sonic

  23. Other Cleaning Applications • The Smart Sonic Stencil Cleaning Process will also perform exceptionally well in the following cleaning applications: • Clean solder paste from misprinted PCBs and tooling • Clean SMD adhesives and conductive adhesives from stencils, misprinted PCBs and tooling • Clean post solder flux residue from pallets, wave solder fingers, oven radiators, heat exchangers, air amplifiers, and tooling Smart Sonic

  24. Summary • The Smart Sonic Stencil Cleaning Process • Guaranteed to clean any type of solder paste from any fine-pitch stencil • Certified environmentally safe, user safe and effective by the Environmental Protection Agency • Cleans without heat • Long chemistry life – Low operating cost • No liquid hazardous waste disposal • Complete turn-key process from one source • Award winning and evaluated by industry experts • Over 1,000 satisfied customers worldwide www.electronics-trading.com smt@electronics-trading.com Smart Sonic

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