|1. Work Instructions
|Is there a revision controlled Operator Work Instruction which contains set-up information for the specific product being reflowed? (Score 0 if any unsigned/undated handwritten instructions or any handwritten instructions more than 48 hrs old)
|Are Work Instructions readily available to the operator and are they followed at Reflow?
|Is the conveyor speed set point specified on the Work Instruction and is it the same as that specified in the program?
|Are the temperature set points specified on the Work Instruction and are they the same as those specified in the program?
|Do Work instructions indicate if pallets or other tooling are required?
|When center rail support is required, do Work instructions indicate this requirement and is the location specified?
|Is the machine Program Name specified on the Work Instruction or set-up sheets?
|2. Machine Capability
|Is the Reflow technology in use suitable for the product being built? Must be full forced Convection with sufficient zone count.
|Are air flow controllers or a centralized control system used to balance exhaust flow rates for each individual exhaust drop?
|Are exhaust flow rate ranges specified and monitored on a regular basis to insure compliance?
|Is the machine Program Name revision controlled to show traceability of program changes?
|Is the machine Program Name traceable to the PWB and PCBA part number?
|Is access to the machine program password protected with restricted access?
|Do program changes to critical parameters during machine control remain unsaved unless approved by a technician/engineer?
|3. Temperature Profile
|Is there available a Temperature Profile for the product currently being built?
|Is the Temperature Profile assessable and readily available to operators / technicians as and when required?
|Were the Temperature Set Points and Conveyor Speed logged for that Thermal Profile when it was conducted?
|Do the Temperature Set Points & Conveyor Speed written on the Thermal Profile correspond to the current Program settings?
|Is there available an Engineering based specification to detail the acceptable process window for Temperature Profiles?
|Was the Engineering based spec. derived from the Paste & Component manufacturer’s recommendations but controlled to a narrower window?
|Does the product Temperature Profile fall within the Engineering based specification for the process window?
|Does the product Temperature Profile fall within the Engineering based specification for glass transition temperature requirements?
|Can any excursions outside of the process window be justified and supported with hard evidence and logical analysis?
|Does the product Temperature Profile meet the reflow requirements for the SMT components according to the component manufactures?
|Are the boards used to establish the initial Thermal Profile kept as engineering samples?
|Is there evidence that a once off comparison study been conducted for a loaded versus an unloaded oven?
|Have at least five thermocouples been used at various points on the board to establish the Thermal Profile? Note*
|Is there a documented and systematic approach used to identify the most appropriate locations to attach the thermocouples?
|Can it be demonstrated that a BOM review was conducted to verify that the chosen profile is appropriate for all specific component conditions?
|Is there evidence that each thermocouple ball was bonded to a board joint using Hi Temp. Solder or Conductive Epoxy?
|Is there the capability to detect a temperature zone failure and to trigger an alarm automatically if this occurs?
|Has a Calibration Profile been established in order to detect machine long term performance degradation?
|Is there a documented frequency for running a Calibration Profile and was it established based upon historical performance data?
|Is there evidence to demonstrate that Calibration Profiles are conducted and that records are up-to-date?
|Is the practice of comparing the current Calibration Profile to the Standardized Calibration Profile used to identify changes?
|Is the current Calibration Overlay/Profile used to determine if a variation in the ovens thermal characteristics has occurred?
|Is the current Calibration Overlay/Profile used to determine if a variation in conveyor speed has occurred?
|Is there evidence to demonstrate that action was taken when the Calibration Profile was different to the Standard?
|Is a standardized tool, like an OvenRider, used with a standardized profile to conduct a Calibration Profile?
|4. Manual Inspection (NA allowed, for questions in this section if AOI is deployed)
|Are outputted boards at least sample inspected pre reflow for placement, missing components, and solder defects?
|Are Workmanship Standards defined for placement and soldering, and are they accessible and used to determine board acceptability?
|Are Inspection Templates available and used to identify missing & unpopulated components and component polarity post reflow?
|Are Inspection Templates or Visual Aids used to identify ICT not tested components post reflow?
|Are Templates readily accessible for verification purposes?
|Are Inspection Templates revision controlled and traceable to the current product ECO level?
|Is there a point and click software tool post reflow which is linked to CAD or program data to facilitate component identification for rework?
|Is there a documented requirement to conduct at least sampling X-ray inspection for BGA devices, and is there evidence that it is practiced?
|5. Automatic Inspection (NA allowed, for the cells indicated)
|Are AOI/AXI complementary methods, which include solder joint inspection, used for all reflowed parts?
|Is the AOI coverage % calculated based on the board OFE for a given side vs the total # of joints/components inspected?
|Are the components/joints not covered by AOI documented and known and targeted for visual inspection?
|Is there evidence that the AOI coverage is verified periodically by using ICT and manual inspection feedback data?
|Can it be demonstrated that the machine calls are reviewed by the operator to determine if real or false?
|Can it be demonstrated that the operator been fully trained and certified to interpolate the AOI images presented?
|Does the ICT pareto of defects suggest that AOI is being 100% deployed and is being effective?
|Can it be demonstrated that AOI detectable ICT failures are feed back to AOI to improve program and operator effectiveness?
|Are rejected boards automatically stopped on the line post operator false call validation?
|Are changes to AOI coverage made based only on performance feedback?
|6. Process Control
|Is there evidence that the SPC used to monitor output post reflow, is effective at identifying & correcting process performance issues?
|Is the processes DPMO and the products DPU monitored in real time? (‘real-time’=now)
|Is OFE data readily available and calculated in accordance to documented procedures?
|Is AOI data used to calculate SMT’s DPMO? Score 0 if AOI deployed and not done.
|Are ICT debug results used to re-calculate SMT DPMO as a true measure of SMT DPMO?
|Is the data collected meaningful and can it be demonstrated that it is used to make process control decisions?