Check can often remind you that your SMD base assembly process is not there are too many variables. Even if your SMD base manufacturing process is able to achieve continuous zero defect production, some form of inspection or monitoring is necessary to ensure the desired quality level. The surface mount assembly is a series of very complex events with lots of individual actions. Our trick is to create a balanced inspection and monitering strategy without a 100% inspection. This article discusses the inspection methods, techniques and manual inspection tools, as well as reviewing the automatic inspection tools and using the inspection results (number and type of defects) to improve the quality of the process and the product.
Check SMD is a product-centric activity, while monitoring is a process-centric activity. Both are required for a quality plan, but the long-term goal should be a little less product inspection and a little more process monitoring. Product inspection is passive (defects have occurred), and process monitoring is active (defects can be prevented) - it is clear that prevention is more valuable than passive responses to existing flaws.
The check is actually a screening process because it tries to find an unacceptable product to repair. Facts are very clear that a large number of checks do not necessarily improve or ensure product quality. Deming 14 points in the third point, said, "do not expect a large number of checks." Deming stressed that a strong process should focus on the establishment of stable, repeatable, statistically monitored process objectives rather than mass inspection. Inspection is a subjective activity, even if there is a considerable degree of training, it is also a difficult task. In many cases, you can call a group of inspectors to evaluate a welding point, but get a few different opinions.
Operator fatigue is why 100% of the check usually does not find the cause of each manufacturing defect, and this is a costly, worthless operation. It rarely achieves the desired product with higher product quality and customer satisfaction.
A few years ago, we began using the term "process monitoring" instead of the inspector, because we wanted to shift the idea of ​​the place of production from passive to active. An inspector usually sits at the end of the assembly line to check the product. In an ideal situation, the process monitoring activity is a balance between product inspection and process monitoring - for example, confirming that the correct process parameters are being used, measuring the performance of the machine, and establishing and analyzing the control chart. Process monitoring takes on a leadership role in these activities; they help the machine operator to accomplish these tasks. Training is a key factor. Process monitors and machine operators must understand the process standards (eg IPC-A-610), the concept of process monitoring and related tools (eg, control charts, Pareto charts, etc.). Process monitors also improve product quality and process monitoring. As a key member of the manufacturing team, the monitor encourages a method of defect prevention, rather than a method of finding and repairing.