Windshield Maker Chooses RFID
Tracking work-in-process through high temperatures andpressure was the challenge for this glass manufacturer. RFID proved to be thesolution.
Visteon Corporation produces components and systems such asclimate control, chassis systems and commercial glass for the auto industry.
The company’s Nashville Glass Plant, producer ofwindshields for Ford Motor Co., faced a dilemma. The current method fortracking windshields — a magnetic coding system — had reliabilityproblems and, more importantly, was obsolete. Visteon realized it needed a morereliable and flexible system for tracking windshield parts. The difficulty itfaced was that any new system would have to survive temperatures of up to300°F and withstand high pressure during the windshield autoclaving andforming process.
Lin Taylor, process and controls engineer, Visteon, says,“We were using an old magnetic tracking system that was no longeravailable. We had considered using a queue in the programming of ourprogrammable logic controller [PLC], but that would have unnecessarilyincreased the size of the PLC, as well as making the programming too complex.That’s when we decided on an RFID solution.”
The company opted for the EMS HMS827 Reader/Writer, the HMS150HT (High-Temperature) Passive Read/Write tags and the CM52 Remote I/OInterface Modules to communicate to the PLC.
Tags are mounted directly to the racks carrying the glass,and travel with the racks through the entire process. The tags can easilyhandle the temperatures and pressures inherent in the autoclaving process. Thereader/writers are attached to conveyors that transport the glass racks. TheHMS827 writes the glass type information of each windshield to the tags priorto autoclaving. After autoclaving, the racks are routed to their correctfinishing destinations based on the tag information detected by the decisionpoint reader/writers.
Taylor says, “The system has absolutely accomplishedthe intended design. It is simple to use. We write the glass type info to thetags and, no matter what happens during the process, the info is stillthere.”
The RFID solution has a lot more capability than wecurrently use, he adds. “Right now, we differentiate between only twolines of information — an ‘A’ part and a ‘B’ part— but, if we ever needed to, the potential to expand the system isthere.” ADF