Inventory Control Comes of Age

RFID tag and barcode technology is becoming mainstream – and may soon be required by specifiers.

By Sue McCraven

Inventory control can be a big headache for precast concrete producers. Project delays mean stock and custom precast products pile up in the yard. For every piece produced and stored, precasters must accurately capture and record: product name; casting, shipping and delivery dates; and installation placement code. Pre-pour and post-pour inspections also must be recorded to comply with industry standards and NPCA plant certification.

Without a centralized system to manage inventory and accurately record product data, process inefficiencies increase, time is lost and paperwork piles up everywhere. Barcode and RFID (radio frequency identification) technologies offer systematic solutions for the precast producer.

Barcode technology in the precast industry works just like it does in retail stores: A scanner reads a barcode label attached to a cured concrete product, which then accesses a computer database for information. It is an easy and cost-effective way to implement product and data tracking into your everyday inventory. RFID tags are small chips that can be cast directly into the concrete product; not only can information be accessed with a scanner, data can be transferred to the chips at any time during or after production, and can even communicate via telephone.

Barcode technology
“Three years ago we converted to the barcode system,” says Josh Martin, director of safety and technology at Terre Hill Concrete Products Inc. in Lancaster County, Pa. “Before barcodes, we used machine-cut stencils and ink rollers to mark our products. Conversion to barcodes took about one year, but in the end, all of our manufactured goods – as well as some of our purchased retail items – were marked with printed barcode labels.”

Compared with stencils, printed barcode labels are much more legible, durable and professional looking, says Martin. “Stencils take time to individually prepare and cut, and the ink can often bleed, fade or become illegible,” he says. “By contrast, thermal-printed barcode labels are very easy to read from a distance with their bright, white background and crisp, dark print. Every manufacturer knows accurate product identification is essential for everyone – from QC personnel, state inspectors, yard crews and truck drivers to field managers and installation crews.”

Martin purchased industrial-grade thermal printers from the start. “Each printer cost about $2,500. Labels cost $175 for a roll of 500, translating into 35 cents per label,” he says. “We place two labels on each piece of concrete as both a backup identifier and to ensure that product information is always visible, even when the pieces are closely stacked in our yard, on a delivery truck or in the field. So our cost is about $1 to label and barcode each piece. Barcode scanner prices vary, depending on the system options desired by the precaster.”

Magda Muka, partner at Muka Development Co., says, “The Titan barcode labels are easily printed directly from production scheduling, inventory or receipt processes. Using a handheld scanner, precasters can track the location of ‘specials’ or custom-made items. No more running around looking for a product to load on the truck.” Information from the barcode is transmitted by the scanner to the Titan II Quality Control Module or Precast Management System.

Martin says that barcodes make a huge difference in his operation. “Barcode technology allows us to more accurately and effectively manage our business processes from beginning to end,” he says. “But I think the big advantage besides labor and cost savings is that this technology forces us to keep current, accurate records.” Successful business requires inventory control, but Martin advises that for this centralized, systematic approach to work, it must be fully understood by every employee from the office staff to the plant workers.

“Before we converted to barcoding, a product could be recorded and identified differently at the time of production, delivery, invoicing or during year-end inventory counts, with the ensuing opportunity for mistakes and delivery errors,” says Martin. “Barcodes label a finished product the exact way it appears in the order, on the delivery tickets and invoices, and on our inventory count sheets at the end of the year. All the information that we, the inspectors and our customers require is right on the label – including the product code and description, job name and number, customer name, production date and product weight.”

Barcode labels offer instant and complete product recognition, adds Martin. “Barcode labels also make an incredible difference for transport and installation of products,” he says. “With a line of trucks waiting to unload pieces for a time-sensitive bridge or box culvert installation, it’s essential to know exactly what piece you’re unloading, how much it weighs, and exactly where it should be installed. With these labels, there is no question when the product is delivered, there is no time wasted trying to locate or read a blurred stencil, all the data needed is printed right on the label and contained within the barcode itself, and there is no need to search through paperwork,” he says.

“A label larger than the 6 in. x 12 in. (150 mm x 610 mm) we use now would provide more room for product information,” Martin adds. “Larger labels could feature our company name and color logo and reflect Terre Hill’s long-standing commitment to quality.”

Another challenge is the label adhesive, according to Martin. “While the labels themselves are virtually indestructible, the adhesive is unreliable. We suspect this is due to new environmental regulations that restrict the use of VOCs.” Martin explained that he had experimented with contact cement applied directly to the concrete before the label is applied with limited results.

“The environment in a precast facility is rugged,” says Martin, “and dirt, efflorescence, weather, and concrete heat and moisture affect adhesives (see “Uninvited Mystery Guest: Efflorescence,” Jan-Feb 2010 Precast Inc. magazine). Finding an adhesive that can withstand these adverse conditions will be necessary before this system will be readily adopted by the industry as a whole.”

RFID technology
Surprisingly, inventory control is not the biggest advantage of RFID technology for Greg Stratis, manager at Shea Concrete Products in Massachusetts. “I’d say the biggest advantage of RFID technology goes beyond accurate inventory and into identifying what stage of production we are at for a particular product,” says Stratis. “On the QC side – and all NPCA-certified plants practice good quality control – we are able to electronically document our pre-pour and post-pour inspections.”

Stratis gives an example: “Say we have multiple castings for a particular job; RFID allows us to know precisely what stage a particular piece is in and what pieces are finished and ready to be delivered. The dispatcher can easily determine that, say, three pieces are ready to go.”

In the past, his QC person would attach plastic tags to the precast product: one tag for pre-pour, one for post-pour. “But all NPCA-certified plants would have to have some method for marking their products, like red and green colored signage,” says Stratis. “We used plastic tags.” The majority of precasters use stencils and ink, crayons or colored spray paint to mark their products for inventory control.

Stratis explained that the plastic tags were time consuming and required a lot of paperwork. “We wanted to capture all our product information electronically,” says Stratis. “RFID is faster and guarantees good quality control with less time and paperwork. Before RFID technology, we had paperwork stacking up all over the place that no one really looked at or analyzed.”

Stratis says that RFID allows him to not only capture all his product data accurately and rapidly, but to analyze it to his advantage with the software system that comes with RFID technology. “It’s easier to identify problems and fix them,” he says. “Since the data is held electronically it is easier to analyze the data for trends.” Using graphs is one example, and other benefits are software-generated alerts and production validation, he says.

“Right now, only one person on our staff uses the RFID reader, and that is our QC person; he is very happy with the system,” says Stratis. “Because the hand-held scanner is not cheap (about $2,000), right now we only have one. But I would like a second scanner permanently mounted on the forklift so that we automatically know where a unit is stored in our yard and when.”

According to Caleb Powers, director of business development at ICT (International Coding Technologies of Beverly, Mass.), handhelds range from $1,500 to $4,000 depending on the functionality needed. Installations for precasters range from $10,000 to $100,000 for some of the larger precasters in multiple locations. “Price is really dependent on the number of handhelds needed, modules in the software (QC, GPS locating, shipping validation, time stamping and other parameters), tags, integration and customer requirements,” he says. Relative to the barcode system, RFID is slightly more expensive. ITC reports that the rate of return on investment (ROI) to the precaster for RFID is about 10 to 12 months.

DCS’s (Data Collection Specialists) Concrete Tracking System (CTS) captures all the data previously mentioned as well as shipping information, such as whether tie-down straps are properly attached to precast on trailers and the weight of the loaded precast (thus avoiding weight-limit issues with DOTs).

“Probably for most precasters, and especially for the smaller mom-and-pop producers, the downside of RFID technology would be the initial cost for the scanner and software,” says Stratis. “However, most people will tell you that the biggest challenge in the RFID industry is the ability to keep the chip from being broken.”

Tom Tilson, president and founder of ICT, explains, “While RFID technology has taken off in the retail, health care and financial service industries, the same cannot be said for the construction industry. This is for several reasons, No. 1 of which is the rugged environment. ICT was founded on bringing RFID technology to construction, railroad and other challenging environments. ICT’s patented Cast-A-Code (CAC) passive RFID tag is designed to be embedded on the surface or within the concrete.”

Brenda Reiland, president of DCS, says, “It is important to understand that the functionality of these systems is in the database, not in the RFID tag or the barcode label. Chips in RFID tags store data, but if the tag is damaged or compromised, data written to the chip may not be readable by the system’s software.”

But don’t expect RFID to replace barcode systems. “RFID tags also have bar codes on them in case the RFID transfer fails,” explains Stratis. “With bar codes, you always have a visual means of identifying the product. I believe precasters will always have a combination of barcoding and RFID technology in the future. You need the barcode backup.”

Future for RFID and barcodes in the precast industry
Stratis believes that precasters will be mandated to use RFID in the future, especially on DOT and FHWA projects. “For state and municipal projects, we may expect that engineering specifiers will require RFID tags,” he says. Transportation engineers will want data from RFID tags for structure monitoring, maintenance and forensic analysis.

“I expect that as these new systems gain in popularity, they will eventually be required as both a means of identifying products and archiving production and installation information,” says Martin. “Especially for federal, state and municipal projects, specifying engineers and inspecting agencies will insist upon the complete and instant data access that this technology can provide.”

Whether you decide on barcodes, RFID or some combination of both, “the idea that barcodes or RFID will solve all the inventory management issues that a precaster faces is a misnomer,” advises Muka. “Inventory management starts before an item is produced. Yes, barcodes and RFID aid in determining what is currently in the yard, but this does little to help determine what ‘should’ be there. Striking the balance between having the right product mix in the yard and having a happy customer is the essence of inventory management.”

Engineers will almost certainly be specifying RFID and barcodes for infrastructure-related precast products. A major North American railroad company has teamed with its precast supplier, for example, to place ICT’s RFID tags into concrete railroad ties. The technology will allow the railroad to monitor millions of precast concrete ties for quality, preventive maintenance and inventory. More importantly to structural engineers, RFID allows a better understanding of the life cycle of precast railroad ties. Collected data will be instrumental in designing a longer service life for railroad, bridge and highway products. Currently, the new Spadina Subway Tunnel Extension in Toronto is casting 53,000 CACs into each precast tunnel segment. Toronto’s provincial planning departments have begun specifying RFID technology in RFPs (request for proposals).

Structural engineers with DOTs, FHWA, and state and municipal agencies are already specifying automated precast data technologies to facilitate infrastructure inspection, monitor concrete performance, schedule maintenance, and conduct forensic analysis. Data from RFID systems can be fed directly into Building Information Models to warn of impending structural issues requiring repair or maintenance (see “How Far Has BIM Come in the Precast Industry?” in the May-June 2010 issue of Precast Inc. magazine and in the Spring 2010 issue of Precast Solutions). Barcodes and RFID technologies are potent tools for the precaster who wants more than just an efficient labeling system.

Sue McCraven, NPCA senior technical consultant, is a civil engineer, technical writer and environmental scientist.

SIDEBAR: How Automatic Identification Data Works

RFID (radio frequency identification) and barcodes eliminate the manual collection of precast product data and greatly reduce recordkeeping paperwork, labor and operating costs.

RFID uses a transponder and an antenna (often called a chip or smart tag), which includes a processor, memory and radio transmitter that are fixed to the surface or embedded in the concrete. Transponders transmit to a reader by means of radio waves. Readers transfer data received to computer software.

Reiland of Data Collection Systems says, “Some mobile computers (scanners) are called EDAs (Enterprise Digital Assistants); these units have the ability to communicate via a LAN (local area network) or WAN (wide area network). EDAs that decode 1-D or 2-D barcodes are fairly new on the market and use cellular technology.” This means that barcode data can be transmitted by the scanner via cell phone towers.

According to Reiland, “The barcode reader talks to the server via the cellular network (WAN) using Sprint, AT&T or Verizon. To the employee working remotely on a job site or in a large yard, all transactions transmit seamlessly over a cellular network.”
Cellular transmission means that accurate product data can be sent to a database that is thousands of miles away. Some EDAs even have cameras that can transmit images from the project site.