Inspection, Detection and Documentation – The Trifecta of Work in Process

As the rolling hills of the Bluegrass state turn from frost covered gold of winter to sun splashed green of spring, most Kentuckians are gearing up for “the most exciting two minutes in sports”, otherwise known as The Kentucky Derby. While some fans are interested in the glitz and glamour of the event, the real supporters of the sport, the bettors, are seeking out a big payday. A specific type of wager called a Trifecta, a bet that requires picking the first three finishers in the correct order, traditionally yields thousands, if not tens of thousands, of dollars in reward. This is no easy feat.  It is difficult to pick one horse, let alone three to finish at the top. So while the bettors are seeking out their big payday with a trifecta, the stakeholders in manufacturing organizations around the globe are utilizing the trifecta to ensure their customers are getting quality products. However, the trifecta of work in process is valued in millions of dollars.

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Work in process, or “WIP”, is an application within manufacturing where the product is tracked from the beginning of the process to the end. The overall goal of tracking the product from start to finish is, among other things, quality assurance. In turn, ensuring the product is of good quality creates loyal customers, prevents product recalls, and satisfies regulations. In a highly competitive manufacturing environment, not being able to ensure quality can be a death sentence for any organization. This is where the trifecta comes back into play. The three processes listed below, when used effectively together, ensure overall product quality and eliminate costly mistakes in manufacturing.

  1. Inspection – Typically executed withWorkinProcess Trifecta a vision system. Just like it sounds, the product is inspected for any irregularities or deviation from “perfect”.
  2. Detection – This is a result of the inspection. If an error is detected action must then be taken to correct it before it is sent to the next station or in some cases the product goes directly to scrap to prevent the investment of any additional resources.
  3. Documentation – Typically executed with RFID technology. The results of the inspection and detection process are written to the RFID tag. Accessing that data at a later time may be necessary to isolate specific component recalls or to prove regulatory compliance.

Whether playing the ponies or manufacturing the next best widget, the trifecta is a necessity in both industries. Utilizing a time tested system of vision and RFID technology has proven effective for quality assurance in manufacturing, but a reliable system for winning the trifecta in the derby is still a work in process.

To learn more about work in process, visit www.balluff.com.

Passive RFID Still the Way To Go For Work In Process (WIP)

With the rapid evolution of manufacturing technology it’s pretty tough to keep up with the latest and greatest products designed to help automate the manufacturing process. The big “buzz” surrounding RFID about a decade or so ago was Wal-Mart declaring that their top one hundred vendors would be required to tag every single item with an RFID tag. Well, that never came to fruition. Around the same time there was a lot of talk about active RFID systems as a new technology for work in process. Well, that didn’t ever quite materialize either.

While the active systems certainly have made an impact on yard and container management applications, passive RFID still rules the roost in WIP. In essence, the main difference between passive and active RFID is active tags require a battery which helps tagsto yield a much larger read range. One can imagine the benefits of an extremely long read range in a shipping yard, but on a production line the engineers are just fine with mounting the read head within a few inches of the work pieces. Eighty to ninety percent of the new WIP applications that we deal with still require High Frequency (HF) technology.   The other ten to twenty percent are using Ultra-High Frequency (UHF) which is still passive technology, just a longer read range. This is usually the case where the actual item being built is very large and it is very difficult to place a HF reader within inches of the work piece.

Ultimately, using active RFID for work in process is similar to using a sledge hammer to put a nail in a wall. It is simply overkill. So, while automation technology is on a course of change, it is clear that some of the “old faithful” equipment is still adequately addressing the needs on the production line.

To learn more about active vs. passive RFID tags, click here.

Identification technology for Work In Process applications is evolving

wipI have had countless conversations over the years regarding barcode vs RFID. Most of those discussions I explained that both technologies have their own unique set of features and benefits and it is rarely the case where they are competing. I still stand by that general argument except when it applies to Work In Process applications. Looking back over the last four to six years there is evidence of a major evolution from barcode to RFID in the production process.

I guess the next question is why is this happening? I am not sure I have the definite answer, but there are a couple consistent factors that tend to come up when we are installing RFID in place of barcode:

Automation – True automation means there are no manual processes. When an operator has to pull a trigger on a barcode scanner the scan is not automated. Even with fixed barcode readers the barcode will sometimes need to be presented to the reader by an operator holding the part. With fixed RFID scanners the part is automatically scanned even without a direct line of sight and even in poor lighting conditions.

ROI – At first glance a barcode solution may seem to be more cost effective than RFID. However, things that need to be taken into account when going the barcode route are: specialized lighting, data management, longevity of the barcode in a harsh environment, etc. With RFID the tags can be read in complete darkness, the data can be managed locally, and the tags are built to survive harsh conditions. In addition, the cost of paper RFID labels has become manageable in the last couple years.

This is definitely something I will be keeping my eye on going forward. With a renewed focus on automation, identification technology will become more and more important as we move toward true automation.

To learn more about industrial RFID systems visit www.balluff.us.