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Wave Soldering. ConveyorPCB transported over the wave . The 6 Basic Steps of Wave/Selective Soldering. Part preparationInsert componentsApply FluxPreheat PCBSolderingCool down. Preforming THT segments. Taken a toll savingHigher generation outputQuality. The impact of opening sizes. Opening size under 1.5 times lead thickness

Presentation Transcript

Slide 1


Slide 2

Wave Soldering Conveyor PCB transported over the wave

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The 6 Basic Steps of Wave/Selective Soldering Component planning Insert parts Apply Flux Preheat PCB Soldering Cool down

Slide 4

Preforming THT segments Cost sparing Higher creation yield Quality

Slide 5

The impact of gap sizes Hole measure under 1.5 circumstances lead thickness – twist of marginally under 90 º A dimple is framed on the lead for gap estimate more than 1.5 circumstances lead thickness Raised from PCB to take into account cleaning or warmth dispersal

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Selective Pallets Stable bolster stage for PCB Eliminate concealing by hand Eliminate stick specking for SMD's Reduce weld deformities, for example, skips and connecting Pockets and channels advances patch stream Standardize transport width – diminish setup time Multiple PCB's on a bed – higher throughput

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The Wave Soldering Process Picture civility of Cobar/Balver Zinn

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Fluxing Why do we require flux? Anticipates oxidation Acts as a wetting specialist Picture obligingness of Cobar/Balver Zinn

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Fluxing – Wave Solder Two normal sorts of fluxing techniques in wave patching: Foam fluxing Spray fluxing Pictures kindness of Seho

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Foam fluxing – Wave Solder Flux control required Ideal contact zone = 20mm Ideal flux stone pore estimate = 3um - 10um Air weight 2 - 3bar Raise or lower the entire flux station to accomplish the correct contact Never utilize a froth fluxer without an air cut Not appropriate for water based fluxes Picture politeness of Seho

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Flux Control (froth fluxer) Critical parameters: Flux thickness (strong substance) Water content Temperature Contamination from PCB or compacted air Replace flux in froth fluxers totally at regular intervals Cleaning of froth pipe

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Spray fluxing - Wave Solder Single side PCB requires 100 Micro Gram for every Cm 2 of PCB surface (Check Flux Data Sheet) PTH PCB's will require 20% more Check the splash design by wrapping a bit of photograph touchy fax paper around an uncovered PCB and let it gone through the fluxer Combination of wind current, flux stream, moving rate, separation of spout to PCB Paper must be equally dark from flux, not wet and unquestionably not trickling Picture civility of Seho

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Advantages of Spray fluxing Quantifiable utilization of the flux store (SPC) No in-process QC of the flux No more slender utilization Direct application from can Reduced flux utilization No flux drippings over the preheat zone Picture graciousness of Seho

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Conversion to Spray flux The 'Plug 'n Spray' shower fluxer Stand alone fluxer Picture affability of Cobar/Balver Zinn Picture cordiality of Seho

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Incorrect Flux Volume Too little flux can bring about binding imperfections, for example, spanning and skips Excessive flux can prompt to weld balling and undesirable and uncured deposit left on the PCB Picture kindness of Bob Willis Picture affability of Cobar/Balver Zinn

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Flux Classification - IPC-J-STD-004

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Flux Types Alcohol based (100% VOC) Long history of unwavering quality & prepare know how Modest in preheat necessities Can be connected by shower or froth High buildup security and wide process window Hazardous & combustible material Contributing to the "green-house" impact

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Flux Types Low-VOC (40% water/60% liquor) Modest in preheat prerequisites Safer to the earth Can be connected by splash or froth High buildup wellbeing and wide process window

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Flux Types Water based (100% sans voc) More fastening force Environmentally safe Non-combustible Requires more preheat Spray fluxing just Some procedure changes required Risk for consumption if flux is not legitimately polymerized by the warmth of the wave (flux under beds, on topside or just an excessive amount of flux connected)

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Preheat Functions of Preheating Evaporation of the dissolvable in the flux Activating the flux Minimizing the Delta T between the PCB and the weld wave Picture kindness of Cobar/Balver Zinn

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Preheat Types of Preheating Infra Red components Quartz components Forced Convection Pictures kindness of Seho

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The Preheat Profile Preheat temperature is measured on the top side of the PCB Typical max. preheat temperature Sn/Pb = 90ºC - 120ºC Typical max. preheat temperature Pb-Free = 100ºC - 130ºC Picture politeness of Cobar/Balver Zinn

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Measuring Preheat Temperature Profiler/Thermocouples Adhesive Temperature Strips Infrared Thermometer Picture kindness of TWS Automation Picture obligingness of www.tempstrips.com

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Measuring Preheat Temperature

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Incorrect Preheat too high or too long may separate the flux actuation framework and cause shorts/icicles Preheat too low may bring about issues, for example, skips or undesirable deposits left on the PCB Picture affability of Cobar/Balver Zinn

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Soldering Phase Wetting Phase Wicking Phase Drain Phase PCB - >> Wave Draining Wicking Wetting Picture cordiality of Cobar/Balver Zinn

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Contact width 7 º Soldering Phase Nominal edge = 7 º Contact Width = 20 to 40mm wide for Delta Wave Contact Width = 15mm wide for Chip Wave Dwell time Tin/Lead = 3.5 sec @ 235 ºC patch pot temperature Dwell time Tin/Lead = 2.5 sec @ 250 ºC weld pot temperature Dwell time Pb-Free = 2 to 5 seconds @ 260-270 ºC bind pot temperature, contingent upon the application Conveyor speed = 0.8 – 1.5 m/min Conveyor speed (m/min) = Contact width (cm) x Dwell time (sec) Wave tallness = 1/3 – 2/3 of PCB thickness High temperature glass plate is utilized to quantify contact width and parallelism to the wave

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Wave Nozzle Configuration Delta Nozzle Standard Nozzle for through gap segments Fast moving bind moving the other way of PCB for wetting activity Small volume of weld moving alongside the PCB for wicking activity Picture civility of Bob Willis Picture graciousness of Seho

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Wave Nozzle Configuration Chip Nozzle Turbulent wave Can be included expansion to the Delta Nozzle High Kinetic Energy Avoids shadowing Picture cordiality of Bob Willis Picture cordiality of Seho

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Wave Nozzle Configuration Dual Wave Turbulent chip wave consolidated with a moderate moving level wave beats the restrictions of other wave sorts Solution for conquering the shadow impact on SMT segments not adjusted to the wave Picture graciousness of Seho Picture kindness of Bob Willis Picture politeness of Seho

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Wave Nozzle Configuration Other Nozzles For segments requiring high wave weight or high stream progression For PCB's with high warm mass To advance contact time Pictures affability of Seho

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Solder Alloy Lead Containing Alloy Sn/Pb Contains Tin/Lead Sn63/Pb37 Melting purpose of 183 ºC Solder pot temperatures from 235 - 250 ºC Eutectic composite – liquefies and hardens at a similar temperature Low surface strain – great wetting Low consistency – extraordinary opening fill and top side filet shaping

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Solder Alloy 4 Popular decisions for Lead-Free SAC (Tin/Silver/Copper) SAC + X (Tin/Silver/Copper + X) SnCu (Tin/Copper) SnCuNi (Tin/Copper/Nickel) Your decision of compound will be dependant on your particular prerequisites

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Solder Alloy SAC Tin/Silver/Copper Typical: Sn96.5/Ag3.0/Cu0.5 Melting purpose of 217 - 221 ºC Solder pot temperature 260 ºC High silver substance Solder joints looks not quite the same as Tin-Lead Dull joints because of shrinkage

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Solder Alloy SAC + X Tin/Silver/Copper + X = Co, Fe, Bi, Si, Ti, Cr, Mn, Ni, Ge, and Zn Typical: Sn98.3 Ag0.3 Cu0.7Bi0.7 Melting purpose of 216 - 225 ºC Solder pot temperature 265ºC Lower material costs versus higher silver SAC combinations Performance and appearance like higher silver SAC amalgams

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Solder Alloy SnCu Tin/Copper Sn99.3/Cu0.7 Melting purpose of 227 ºC (Eutectic amalgam) No silver substance - brings composite cost Lower inclination down to filter copper - less loss of conductive copper in tracks and cushions Poor smoothness at common lead free temperatures Poor through-gap filling and framing of bind extensions between segments

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Solder Alloy SnCuNi Tin/Copper/Nickel Sn99.25/Cu0.7/Ni0.05 Melting purpose of 227 ºC Eutectic composite – free of shrinkage Solder pot temperatures from 265 ºC Does not contain silver - running expenses are low Small expansion of nickel into the SnCu composite enhances ease Good ease – less scaffolds and better gap –filling Dross rate equivalent or lower than tin-lead bind Lower forcefulness towards stainless steel Bright smooth weld joints

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Solder Bath Analysis For Tin-Lead, each 3 to 6 months For Lead-Free, every 4 – a month and a half after starting fill amid the initial 6 months, from there on each 3 to 6 months is prescribed

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Transition to Lead Free Alloys Higher preheat temperatures required Corrosion of metal parts Pictures kindness of Seho

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Solutions for Lead-Free Pause the PCB in the preheater Coated parts accessible, pumps, bind spouts and bind pot Pictures civility of Seho

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Cooling Phase Forced cooling or not? No change in joint quality To accelerate generation Picture cordiality of Cobar/Balver Zinn

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Nitrogen or Not? Uproots oxygen Reduced dross arrangement Increase surface pressure Improved stream of weld Better wetting Pictures cordiality of Seho

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Most basic reasons for issues

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Thank you for your Attention Any Questions? www.smartgroupsa.org PEM Technologies BRINGING TECHNOLOGY TO THE INDUSTRY www.pemtech.co.za