In today's economy, managing quality is an imperative
How en emphasis on quality can drive savings and add capacity
Today more than ever, it is critical for companies to ship high quality products to market. It is imperative to have good practices in place, including the use of good product quality management software, for tracking product quality throughout a product’s lifecycle and for lowering production costs. Tracking product quality in real time is key to managing costs.
OEMs and plant managers are often faced with many disparate issues during manufacturing. On top of this, they are often challenged with sorting through reams of data to determine which issues should be addressed and which ignored. For instance, consider false calls. Often operators will visually inspect a board and determine that a false call should not be considered false. Yet, if a company is getting an inordinate number of false calls in a month, in some situations as many as 1,000, this presents a cause for further investigation.
Reading through lengthy test reports often isn’t the answer, plus these reports often take weeks to generate/receive. Instead teams need real-time insight into processes and events causing issues. Product quality management software is often the answer. Ideally the software should include an easy to use dashboard, be available on-demand, and it should drill down to the root cause of errors and provide warnings and alerts when products or processes are going awry.
An operator may not know why a percentage of boards are failing. Yet, if the same operator could instead tell that 30% of the components that were installed in slot 45 failed on a series of boards, that would be increasingly valuable. If he can determine that the boards failed because a component was soldered incorrectly, placed sideways or due to another variable this would be even more valuable. If defects can be identified at AXI vs. functional test, this can result in tremendous savings.
Determining why “passed” product failed
Boards will often pass many manufacturing tests, but after use in the field they can fail. Consider a scenario whereby three oscillators were being used in every printed circuit board; they worked initially but start to fail within a week of use in the field. Initially there isn’t a way to determine that the oscillators’ crystal blanks were not properly etched, and the supplier had a track record of providing high-quality components.
With quality management software, users can use analytics features to find like boards, showing the same characteristics as the defective products that had initially passed In-Circuit Test. From there, the software can provide serial numbers of other boards with the defective oscillators. Then it is easy to replace the defective components with good parts and retest them prior to shipping additional products to customers.
Getting reliable yield information
With product quality management software, it is easy to determine if contract manufacturing reports claiming 90% pass rates of boards following ICT and 5DX (automated x-ray inspection) are indeed accurate. Operators can make assumptions that failed products should instead be passed products, i.e., via visual inspection, and make reports accordingly. Product quality management software pulls data directly from any tester source, providing its own pass/fail data along with important parameter data.
Moreover, limit information on components in the board that failed can be analyzed. For example, if a particular register should operate at operate at 7 ohms, the software can show the number of registers outside the lower limit of 4 ohms and above the upper limit of 10 ohms. From there, the serial numbers of the boards with defective ohms can be pulled and the defective registers can be easily replaced.
Warnings and alerts: Users can set exact process indicators to track and automatically get email and pager alerts with warnings indicating when issues need investigating. The alerts go out when target yields are outside of acceptably determined limits (e.g., below 95%). Since this information is presented in real time, as opposed to several weeks later, plant managers can solve problems quickly--significantly reducing rework and remanufacturing time as well as investment.
Tracking capacity: Today as companies are trying to manage costs, they want to avoid being presented with a request for more dollars for increased manufacturing capacity. Product quality management software identifies how many hours each test station is used each day and tracks the amount of time it takes the stations to test each product. With this, users can determine if existing test stations can run longer hours. As fixtures are as much as $100,000, having precise capacity information is key to managing costs.
Minimizing line card and other failures: Manufacturing always brings up new situations, yet the goal is to have as few problems as possible. If a component is placed in the wrong slot, this could be easy or hard to identify, pending the processes in place. Product quality management compares the characteristic of properly installed components vs. improperly installed components. From there, the lots of improperly assembled products can be fixed.
Victor Nelson is recognized for successfully leading quality and manufacturing operations at Force10. He focuses on: quality system implementation, business intelligence, performance monitoring and high availability modeling for large scale networks. Al Alaverdi is vice president of Technology at SigmaQuest.