In order to maintain strict quality control of the approximate 700 000 engines produced at Ford Essex annually, an automatic data capture system was required to ensure product traceability and quality.
Ford Motor Company's Essex engine plant in Windsor, Ontario, Canada, manufactures 11 different engine types under one roof. Ford Essex manufactures such diverse engines as manual vs. automatic, 3,8 litre vs. 4,2 litre, '00 vs. '01 model year and South American vs. North American specifications.
According to Michael Loch, Technical Sales Representative at Trade Electric which integrated the Ford Essex automation system, "Ford needed a tracking and identification system that could store build information such as whether a piston was installed in the correct location, or a nut was torqued correctly." Michael Loch added that, "The ID system had to be able to withstand demanding environment conditions. Tracking mechanisms had to endure the same conditions as the machined engine parts, often being rinsed in hot, soapy water, then dried at 60° temperatures and finally sprayed with oil. Equally importantly, the ID system had to interface with Allen-Bradley's PLC 5."
After an in-depth analysis of the various automatic identification capture technologies in the marketplace, Ford Essex decided that radio frequency identification, or RFID, was the solution. RFID involves placing a tag onto a product or product carrier and communicating data by means of radio frequency signals from the antenna (or reader/writer) to the tag.
Next, Ford Essex was faced with the challenge of evaluating RFID companies to determine which provider would offer the most reliable products and the best technical support. Of the handful of selected candidates, Ford Essex chose Escort Memory Systems' RFID products and network interface modules. Escort Memory Systems has a long history of producing innovative RFID products and a strong reputation for ensuring that each of its automation projects is a success.
Ford's decision to use Escort Memory Systems products was further solidified by the fact that numerous other Ford plants used Escort Memory Systems RFID products with very favourable results.
Dave Mathias, Electrical Team Leader at Ford Essex, states that, "We were very impressed with Escort Memory Systems' HS208R read/write tags. The tags provide the best read/write speed, have plenty of memory and are encased in tough industrial enclosures. The tags have proven to be extremely reliable, as they are routinely exposed to hot water, grease, soap, noise and vibrations."
Tim Eisler, Sales Manager for Escort Memory Systems, sums up the identification system as applied in the initial steps of the manufacturing process. "The tags are bracket-mounted directly onto the engine block after the engine has completed the piston bore station. Communicating to the RF tags are Escort Memory Systems' HS500A read/write antennas. At the onset of the manufacturing process, the HS500A antennas transmit such data as serial and model numbers to the tag."
Loch further explains: "As the engine is transferred to the assembly line, where multiple lines converge (for example, cams and pistons), the data on the engine tag is transferred to another tag which is mounted on the engine pallet. One antenna reads the data on the engine tag and transmits this information to the PLC 5 via an Escort Memory Systems' HS880B controller. The HS880B connects directly to Allen-Bradley's PLC 5 via an Allen-Bradley 1771DB module. This same data is then transmitted via another antenna to the engine pallet tag."
As the engine travels through each of the approximate 2000 workstations, manufacturing process data is transferred to the tag as a pass/fail. As each station is completed, an antenna writes manufacturing data to the tag. As the engine pallet approaches the next station, an antenna reads the tag to confirm the engine successfully completed the previous station. If the tag has a fail reading, the engine continues through the process but without being worked on at subsequent stations, until it reaches the repair bay. Ford Essex was able to use the RFID system to streamline the engine repair process. If an engine failed the final test, engineers no longer had to tear apart the engine to determine the problem. Instead, the engineers were able to analyse the stored build data in the RFID tag to pinpoint the concern.
Dave Mathias, reflecting back on how identification systems have evolved, states that, "Ford used bar codes to track engines several years ago but the labels had difficulties surviving in this harsh environment and you cannot write data to a barcode label. You can put more information on an RFID tag - in fact, we only use half the memory of the HS208R tag which gives us plenty of room for future expansion."
Jim Kott, data capture spokesman for Allen-Bradley Rockwell Automation, agrees. "Allen-Bradley is committed to offering system-wide automation solutions in RFID technology with our Encompass Partner - Escort Memory Systems."
Escort Memory Systems
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