Batch Tracking in Aluminum Heat Treating
Mike Boggs and Steve Carr - Alfe Heat Treating, Inc.Not too long ago, aluminum heat treating was more of an art than a science. Achieving consistency from batch to batch required a skilled operator, a perfectly maintained furnace and a little luck. Documentation for each batch was limited to a hand-drawn chart and the assurance that "that's how it ran" - not exactly the sort of reassurance you would expect in a critical automotive or aerospace application. The use of computer technology has allowed for better control of the process and tighter tolerances. With IT-based control systems, furnace operations can be programmed and repeated precisely, giving customers the assurance that their parts will be exactly the same. Today's technology allows for positive tracking of each batch, making it easier to establish and maintain work schedules. Bar coding is a critical component of this tracking feature. With advances in programming, today's heat treat systems now have the ability to reject batches if certain criteria are not met.
Traditionally customers relied on operators to ensure consistency in Aluminum Heat Treatment. The only records available were manual logs and paper charts. In today's market inventory tracking, and process tracking have been facilitated by new information technology systems. This has been true in all sectors of Alfe business including NADCAP, Military, and automotive.
At its Defiance, OH aluminum heat treat plant, Alfe has been able to let its nearby customer (GM) see in real time where every part is in the process, and immediately review the processing conditions if necessary. The tracking is accomplished using 2D bar coding on each basket of parts to allow scanners to link specific parts to location and heat treatment data information in real time. This allows GM to have complete "just-in-time" information for itself and the machine shop which is adjacent to Alfe and received its parts direct from heat treatment through the wall. The use of the 2D coding technology has lead to much more accurate scanning than was possible with traditional linear bar codes. Using special textured stamps the 2D codes are also stamped directly on non-machined areas of the castings themselves making complete traceability possible for the life of the item. The customer has immediate access to all data the Alfe has via secure internet connection. Much of the tracking software is in Visual Basic and was developed by Alfe itself. Instrumentation data displays are largely from the heat treat instrument providers.
Most of the product at the Defiance Plant is lost foam Aluminum castings. In all Alfe has 9 heat treating facilities in the US, all of which east of the Mississippi. In addition to aluminum, some facilities heat treat ferrous metals as well.