cleaning process do's and don’ts. - smta€¦ · evolution of technology – board and...
TRANSCRIPT
![Page 1: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/1.jpg)
Presented by:Scott F. Cain
Original Slides by: Debbie Carboni
Kyzen Corp
Cleaning Process Do's and Don’ts.
Avoiding Common Pitfalls...
![Page 2: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/2.jpg)
Evolution of technology – Board and Equipment
Board Design Considerations
Overcoming Environmental Challenges
Common machine set up blunders
Common Process Control blunders.
Common board fixturing blunders
Is your rinse effective enough?
How to effectively clean to meet the new standards, be reliable and prove it.
The Next 60+ Minutes
![Page 3: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/3.jpg)
GOAL:
Answer your
questions
![Page 4: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/4.jpg)
Modern Cleaning and Equipment
![Page 5: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/5.jpg)
Evolution of Technology, Cleaning Methodology & Validation
![Page 6: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/6.jpg)
Demand
High Frequency Devices
High Impedance Devices
High Voltage Devices
10 year+ life
Conformal Coated PCB
Products functioning in a Harsh
Environment
![Page 7: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/7.jpg)
Component Challenges
Source: Dale Lee of Plexus Source: Bob Willis Consulting
These images are videos – double click to view
![Page 8: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/8.jpg)
Customized tests
No Clean Paste Can Lead to Electrochemical Migration
I 295mA
24.4 mil
In-situ monitoring of
dendritic growth
Flu
x A
F
lux B
Custom-designed board
Bias 12V/mm
![Page 9: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/9.jpg)
Cleaning or Considering Today
![Page 10: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/10.jpg)
Modern Spray-in-Air Cleaning Tools
Factors that impact the rate function
Deflection energy (i.e., pressure at the board surface)
Nozzles type
Coverage
![Page 11: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/11.jpg)
Modern Cleaning Agents
Both Inorganic and Organic in nature Solvent Phase
Targeted at non-polar soils
Aqueous Phase Targeted at polar soils
Functional additives Defoaming
Corrosion Inhibition
Lower surface tension
Bath life and loading
Rinsing
![Page 12: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/12.jpg)
The Cleaning Process is Dynamic
![Page 13: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/13.jpg)
BOARD DESIGN
CONSIDERATIONS
![Page 14: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/14.jpg)
Eliminate ALL BTC’s
Solution #1 – Optimize PCB Design
![Page 15: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/15.jpg)
Engineer For Cleanability
Make It Easy…ier
Access To Flux Residues Component to Component Spacing
Component Standoff Height
Solder Mask Clearance
Silk Screen Clearance
Solder Mask Type
Redirecting Flux Residue Location Between Pins & Thermal Pad (QFN)
Flux Cleanability
![Page 16: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/16.jpg)
Access To Flux Residue
Board Layout
Increase Spacing Between
Components
Low Standoff Component
Large Package Size Components I.E. – High IO BGA’s/LGA’s
Tall Component Packages
![Page 17: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/17.jpg)
Improved Access To Flux Residue
Increased Component Standoff Height
Solder Mask Design SMD, NSMD, No Solder Mask
Pad Design Thicker Copper – 1 oz > 2 oz > etc.
Smaller Lead To Pad Area Aspect Ratio –
Component Package Specific
Use Silk Screen to raise BTC corners
Remove Silk screen body outline to allow
for flow.
Dale Lee, Plexus
![Page 18: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/18.jpg)
BTC Via Holes and Solder Mask
NSMD is better except for BGAs
![Page 19: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/19.jpg)
Solder Mask Selection
Matte Finish Solder Mask Has Increase Surface Energy To Hold Flux To The Board (More Flux For Solder Joint Formation)
Dull/Low Reflection Appearance
More Difficult To Clean
Glossy Finish Solder Mask Has Low Surface Energy to hold Flux To The Board (Less Flux For Solder Joint Formation – Solder Balls, Icicles, Flags, etc.)
Highly Reflective Appearance
Easier To Clean
Not Preferred
Preferred
Dale Lee, Plexus
![Page 20: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/20.jpg)
ENVIRONMENTAL
CONSIDERATIONS
![Page 21: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/21.jpg)
Over coming Environmental Challenges
![Page 22: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/22.jpg)
Global Harmonized System Internationally agreed upon standard
Hazard testing criteria
Universal warning pictograms
Safety data sheets with required information Hazard Classification
Physical Hazards
Flammability
Toxic substances
Health Hazards
Acute toxicity
Chronic toxicity
Environmental Hazards
Air
Water
Classification of mixtures
![Page 23: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/23.jpg)
What does YOUR Local Publicly/Privately Owned Treatment Works considers Environmentally
friendly?
Biochemical oxygen demand (BOD) Limits vary even within same country/state
Chemical Oxygen Demand (COD) Limits vary even within same country/state
Total Solids – Mostly concerned with lead contamination
pH of waste water Generally treatment plants allow a pH range of 6-10
pH neutral does not mean wash solution is Safe to send to drain or to a waste water
treatment
Waste Water Management
![Page 24: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/24.jpg)
Smell (while subjective) has an impact consciously and subconsciously.
Should not be strong
Should NOT Cause Physical reactions: Eye Irritations, skin irritation, Headache, Nausea
Machine Maintenance
Cause excessive scrubbing/rinsing in the wash or rinse tanks to keep the process in the process
limits
Ease of Concentration Monitoring
Real Time concentration Monitoring available
Eliminates operator from having to take taking manual concentration readings
Human Contact/Operator Experience
![Page 25: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/25.jpg)
What’s in the Wash Bath?
![Page 26: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/26.jpg)
Kapton Tape
Solder Balls
Solder Mask Materials
Paste/Flux
Unplanned contamination: Glue, underfill, Thread lock material, RTV,
Epoxy, grease….3rd SHIFT
Its not just Water and SOAP!
![Page 27: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/27.jpg)
pH Balance
Typical Flux: 2 4 Modern Cleaning agents 7.5 10.5
![Page 28: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/28.jpg)
COD/BOD Balance
Typically the lower the pH, the higher the COD
![Page 29: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/29.jpg)
MACHINE SET UP BLUNDERS
Common
![Page 30: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/30.jpg)
3. Water Supply
2. Nozzle Adjustments
1. Exhaust
Top 3 Set up Mistakes
![Page 31: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/31.jpg)
Should be DI water for entire machine ALL the time. Good quality- Minimum 2 megohm (or your Set point)
low level set point.
Plumbing material: Material
DI water eats copper
Inlines: Enough to provide good flow in final rinse when other
parts of the machine are calling for water. Wash or rinse tank is filling (total of 38-40 liters/10-
12gallon per minute demand)
Water Supply
![Page 32: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/32.jpg)
Nozzle Alignment
Fluid delivery should be across the entire assembly(s)
![Page 33: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/33.jpg)
Spray bar alignment can impact the cleanliness effectiveness
Perpendicular on most spray is recommended
Slightly turn the airknife toward wash section
Deflector Plates on top of wash
Curtains between wash and chemical isolation sections
Inline Spray/Air Alignment
![Page 34: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/34.jpg)
Other Blunders
Original ducting
should sit inside
Demister collar
at top side.
Demister collar
should sit inside
ducting/collar
from cleaning
machine.
![Page 35: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/35.jpg)
Blunders Results
![Page 36: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/36.jpg)
Best Installation Practices
![Page 37: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/37.jpg)
PROCESS CONTROL
BLUNDERS
Common
![Page 38: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/38.jpg)
Semi Automatic/Manual Monitoring
![Page 39: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/39.jpg)
Data logging
Automate as much as possible
Use your machine alarm settings
with a window that meets your
cleanliness needs.
Don’t Ignore Alarms
Don’t forget Rinse and Dry
Process Control
![Page 40: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/40.jpg)
Keep nozzles clean
Keep wash tanks clean
Keep Rinse water clean
PM – Daily/Weekly
PM’s and Alarms are the Key to Repeatability
![Page 41: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/41.jpg)
BOARD FIXTURING AND
POSITIONING BLUNDERS
Common
![Page 42: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/42.jpg)
Inline Top Spray Bars. Vs Bottom
More impingement energy from the top sprays
Place more difficult to clean facing towards the highest energy
Some machines do not have complete spray over entire converyor. The conveyor belt rail can cause a 1” Dead Zone on the bottom side sprays
When possible, clean between soldering processes
![Page 43: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/43.jpg)
Understanding the batch Chamber Some Batch Machines
Not all boards may see the say pressure
Corners may have 2-3” Low pressure/flow
![Page 44: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/44.jpg)
Batch Board Orientation
Avoid tall boards too close to short boards to avoid
Potential Shadowing When loading the basket
Boards should be spaced 1-3 inches apart
depending on potential shadowing and complexity
of assembly
Most complex assembly side down towards bottom
Face Connectors face down
Electrolytic Caps should be faced away from direct
heat source (heating element) if possible Or run
less than 130F
![Page 45: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/45.jpg)
Ensures proper &
repeatable cleaning
Prevents foaming in the
rinse
Reduces costs
Reduces chemical drag-out
Reduces re-cleaning
Bad
Good
Proper spacing between pallets /PCB’s is key
Bad
![Page 46: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/46.jpg)
Batch Fixturing
![Page 47: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/47.jpg)
Inline Fixturing Designs
CONVEYOR BELT SECTIONS TO
PLACE ON TOP OF CONVEYOR
(NOT IN SAME DIRECTION)
![Page 48: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/48.jpg)
![Page 49: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/49.jpg)
A few more Bad Designs
![Page 50: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/50.jpg)
Baskets Done Wrong • Decent open area
• ½” mesh belt is better
• Round wire mesh has
less drag-out.
Stamped metal, causes:
• Small opening shadows
components
• Diffuses impingement energy
(wash and rinse)
• Excessive drag-out
• Foaming in rinse
Top Hold good
Bottom Bad
![Page 51: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/51.jpg)
Basket Board Spacing Improves cleaning by:
Spacing between assembly to prevent PCBs
on top of each other.
Open mesh or no mesh to allow for direct
energy each other
Bad
![Page 52: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/52.jpg)
Pallet Considerations Raised closer to the sprays
increases energy Know what the height
limitation on the sprays
Total Height with pallet needs to be less than sprayable area
Open slots and holes for good drainage and less weight. Reduces excessive chemical
use
Prevents foaming in the rinse
![Page 53: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/53.jpg)
Use the Whole Belt Keep 2-4” between pallets to prevent
excessive wash solution loss
![Page 54: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/54.jpg)
PCB Placement to Improve Through Put
20" Conveyor 26" Conveyor
Assembly Length (in) 9.5"
Assembly Width (in) 3.5"
Spacing between assemblies 4
Multiple lane processing 2
capacity (boards/hour)
Throughput requirement (no. of boards/day) 5000
hours per day 23
boards needed per hour 217
boards needed per min 4
![Page 55: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/55.jpg)
DON’T FORGET RINSING
![Page 56: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/56.jpg)
Rinsing Issues Often observed under low standoff devices, tight spaces/crevices, and
connectors
Worsen with bath loading
Effectiveness on rinsing cannot be analyzed by ionic cleanliness
assessment methods
A common root cause of downstream process problems such as
conformal coating defects by poor adhesion and wetting
Possible intermittent shorts.
Final Cleanliness
![Page 57: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/57.jpg)
Quick and Easy Surface Test
BAD
Poor wetting Poor adhesion
GOOD Clean Surface
![Page 58: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/58.jpg)
Factors that Improve Rinsing Hot DI-water
Rinse zone is as important as the wash zone
Rinse time
Rinse pressure
Understanding the effects of FLUX Soil Loading
BAD
Poor wetting
Poor adhesion
GOOD Clean Surface
![Page 59: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/59.jpg)
BE RELIABLE AND PROVE IT
How to effectively clean to meet the new standards,
![Page 60: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/60.jpg)
On-Site Test Methods to Meet J-STD-001 Rev G.
Without Objective Evidence, Your “Number” does not mean Anything
![Page 61: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/61.jpg)
Qualification vs. Production
Qualification
No flux loading
Visual, IC, Ionograph, and SIR
Rarely include rinse test.
No downstream process impact
assessment.
Single design test assemblies are
used. And may not have the same
components
Production
Heavy flux loading.
Visual/ Ionograph
Adhesion and wetting are critical to
downstream processes.
Wide variety of assembly geometries
(shadowing, entrapment, etc.)
Rework- unexpected work arounds
![Page 62: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/62.jpg)
Cleaning Equipment and Parameters
Wash, Rinse, Dry
Handling
Process Control
Maintenance
Cleaning is A PROCESS
![Page 63: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/63.jpg)
Cleaning Process Do’s and Don’ts
1. Set up your process Correct from the start
2. Understand the cause and effect each setting
3. Pay attention to board position and handling
4. Cleaning is not just the Wash Stage
5. New Process Control Tools are being introduced that can
provide process optimization and monitoring to meet
tomorrow’s challenges
![Page 64: Cleaning Process Do's and Don’ts. - SMTA€¦ · Evolution of technology – Board and Equipment Board Design Considerations Overcoming Environmental Challenges Common machine set](https://reader036.vdocument.in/reader036/viewer/2022070706/5e9ec6962d7bcb65f35a9aee/html5/thumbnails/64.jpg)
Scott Cain Western Regional Manager [email protected] Debbie Carboni Global Product Manager, Electronics [email protected]
Questions?