1. Work Instructions |
|
1.1 |
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) |
1.2 |
Are Work Instructions readily available to the operator and are they followed at Reflow? |
1.3 |
Is the conveyor speed set point specified on the Work Instruction and is it the same as that specified in the program? |
1.4 |
Are the temperature set points specified on the Work Instruction and are they the same as those specified in the program? |
1.5 |
Do Work instructions indicate if pallets or other tooling are required? |
1.6 |
When center rail support is required, do Work instructions indicate this requirement and is the location specified? |
1.7 |
Is the machine Program Name specified on the Work Instruction or set-up sheets? |
2. Machine Capability |
|
2.1 |
Is the Reflow technology in use suitable for the product being built? Must be full forced Convection with sufficient zone count. |
2.2 |
Are air flow controllers or a centralized control system used to balance exhaust flow rates for each individual exhaust drop? |
2.3 |
Are exhaust flow rate ranges specified and monitored on a regular basis to insure compliance? |
2.4 |
Is the machine Program Name revision controlled to show traceability of program changes? |
2.5 |
Is the machine Program Name traceable to the PWB and PCBA part number? |
2.6 |
Is access to the machine program password protected with restricted access? |
2.7 |
Do program changes to critical parameters during machine control remain unsaved unless approved by a technician/engineer? |
3. Temperature Profile |
|
3.1 |
Is there available a Temperature Profile for the product currently being built? |
3.2 |
Is the Temperature Profile assessable and readily available to operators / technicians as and when required? |
3.3 |
Were the Temperature Set Points and Conveyor Speed logged for that Thermal Profile when it was conducted? |
3.4 |
Do the Temperature Set Points & Conveyor Speed written on the Thermal Profile correspond to the current Program settings? |
3.5 |
Is there available an Engineering based specification to detail the acceptable process window for Temperature Profiles? |
3.6 |
Was the Engineering based spec. derived from the Paste & Component manufacturer’s recommendations but controlled to a narrower window? |
3.7 |
Does the product Temperature Profile fall within the Engineering based specification for the process window? |
3.8 |
Does the product Temperature Profile fall within the Engineering based specification for glass transition temperature requirements? |
3.9 |
Can any excursions outside of the process window be justified and supported with hard evidence and logical analysis? |
3.10 |
Does the product Temperature Profile meet the reflow requirements for the SMT components according to the component manufactures? |
3.11 |
Are the boards used to establish the initial Thermal Profile kept as engineering samples? |
3.12 |
Is there evidence that a once off comparison study been conducted for a loaded versus an unloaded oven? |
3.13 |
Have at least five thermocouples been used at various points on the board to establish the Thermal Profile? Note* |
3.14 |
Is there a documented and systematic approach used to identify the most appropriate locations to attach the thermocouples? |
3.15 |
Can it be demonstrated that a BOM review was conducted to verify that the chosen profile is appropriate for all specific component conditions? |
3.16 |
Is there evidence that each thermocouple ball was bonded to a board joint using Hi Temp. Solder or Conductive Epoxy? |
3.17 |
Is there the capability to detect a temperature zone failure and to trigger an alarm automatically if this occurs? |
3.18 |
Has a Calibration Profile been established in order to detect machine long term performance degradation? |
3.19 |
Is there a documented frequency for running a Calibration Profile and was it established based upon historical performance data? |
3.20 |
Is there evidence to demonstrate that Calibration Profiles are conducted and that records are up-to-date? |
3.21 |
Is the practice of comparing the current Calibration Profile to the Standardized Calibration Profile used to identify changes? |
3.22 |
Is the current Calibration Overlay/Profile used to determine if a variation in the ovens thermal characteristics has occurred? |
3.23 |
Is the current Calibration Overlay/Profile used to determine if a variation in conveyor speed has occurred? |
3.24 |
Is there evidence to demonstrate that action was taken when the Calibration Profile was different to the Standard? |
3.25 |
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) |
|
4.1 |
Are outputted boards at least sample inspected pre reflow for placement, missing components, and solder defects? |
4.2 |
Are Workmanship Standards defined for placement and soldering, and are they accessible and used to determine board acceptability? |
4.3 |
Are Inspection Templates available and used to identify missing & unpopulated components and component polarity post reflow? |
4.4 |
Are Inspection Templates or Visual Aids used to identify ICT not tested components post reflow? |
4.5 |
Are Templates readily accessible for verification purposes? |
4.6 |
Are Inspection Templates revision controlled and traceable to the current product ECO level? |
4.7 |
Is there a point and click software tool post reflow which is linked to CAD or program data to facilitate component identification for rework? |
4.8 |
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) |
|
5.1 |
Are AOI/AXI complementary methods, which include solder joint inspection, used for all reflowed parts? |
5.2 |
Is the AOI coverage % calculated based on the board OFE for a given side vs the total # of joints/components inspected? |
5.3 |
Are the components/joints not covered by AOI documented and known and targeted for visual inspection? |
5.4 |
Is there evidence that the AOI coverage is verified periodically by using ICT and manual inspection feedback data? |
5.5 |
Can it be demonstrated that the machine calls are reviewed by the operator to determine if real or false? |
5.6 |
Can it be demonstrated that the operator been fully trained and certified to interpolate the AOI images presented? |
5.7 |
Does the ICT pareto of defects suggest that AOI is being 100% deployed and is being effective? |
5.8 |
Can it be demonstrated that AOI detectable ICT failures are feed back to AOI to improve program and operator effectiveness? |
5.9 |
Are rejected boards automatically stopped on the line post operator false call validation? |
5.10 |
Are changes to AOI coverage made based only on performance feedback? |
6. Process Control |
|
6.1 |
Is there evidence that the SPC used to monitor output post reflow, is effective at identifying & correcting process performance issues? |
6.2 |
Is the processes DPMO and the products DPU monitored in real time? (‘real-time’=now) |
6.3 |
Is OFE data readily available and calculated in accordance to documented procedures? |
6.4 |
Is AOI data used to calculate SMT’s DPMO? Score 0 if AOI deployed and not done. |
6.5 |
Are ICT debug results used to re-calculate SMT DPMO as a true measure of SMT DPMO? |
6.6 |
Is the data collected meaningful and can it be demonstrated that it is used to make process control decisions? |