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38 SMT Magazine • September 2014 enough controllable zones in the reflow oven allow for controlled escalation to reflow tem- perature, exposure time in the reflow zone and a controlled return to ambient temperature. All of these elements must be accounted for in de- signing the reflow profile. Placing an automated X-ray inspection (AXI) station in-line following reflow will provide the data to tie the entire process together. The AXI offers real-time feedback for process adjustments throughout the SMT process. AXI systems with automated inspection software will meet the industry requirements for high accuracy and high speed at the same time. Traditional X-ray processes are manually intensive and subject to interpretation. Interpreting the data collected by the AXI will provide information that may be used to validate stencil modifications, pick- and-place processing and reflow oven profiles. Relying on human inspection for this feedback will prove valuable only to the point of fatigue where advantages will decrease to the point of creating issues and defect escapes rather than contributing to their solutions. Automation, when properly maintained, is not subject to the same fatigue, virtually eliminating the human error factor. Comparing results before and after a modification to a process becomes more reli- able when facts and data are accurately record- ed and do not depend on human recollection. Automated optical inspection (AOI) is uti- lized to detect solder defects, component pres- ence and position, verify the correct part is in- stalled, polarity, solder paste uniformity and fine pitch lifted leads. The data is linked to our quality management system (QMS) and features direct statistical process control (SPC) outputs. This advanced automation is not inexpen- sive. A highly automated SMT line like ours will exceed $3 million in machine cost and imple- mentation, and qualification manpower will add significant cost to this investment. Rudi- mentary ROI analyses will prove that the speed and consistency resulting in higher quality and reliability in the end item will easily offset the implementation cost. This saving is the result of dramatically reduced manpower required to du- plicate what automation is capable of achieving through reduced operator intervention, inspec- tion effort and reduced or eliminated rework cycles that drive up cost and throughput times. From an organizational perspective, our in- vestments in advanced automation equipment and processes have paid tremendous dividends. We were recently recognized in our market place for manufacturing superior quality prod- ucts that are utilized in mission-critical mili- tary C4ISR systems in support of our nation's defense, and our success has provided us the opportunity to continue to grow and add ad- ditional customers and employees. Smt AUtOmAtION'S INFLUeNCe ON ASSembLy QUALIty continues feATure Waleid Jabai is vice president of manufacturing at Zentech Manufacturing Inc.