The Dow Chemical facility in Freeport, Texas, packages more than 100 different liquid chemical products, including glycerine and glycol, in 55-gallon metal and plastic drums. The plant processes both hazardous and nonhazardous chemicals and operates on a drum-to-order basis.
It keeps filled drums in inventory to a minimum to save both money and space. That means it is producing lots of small batches, and because of the nature of its products, accurate labeling is a must.
Prior to the spring of 2001, Dow was using manual methods almost exclusively to fill and label its drums. The facility had six separate filling/packaging lines located around the facility floor, each staffed by two or three employees.
The drums were filled using what project manager Joe Hairston calls the "cotton-scale-and-a-hose" method: Drums were routed via conveyor to an operator who unscrewed the bung, put in the filling lance and filled the drum, put it on a scale, put the bung back in, capped the drum and moved it down the line. After all that, another operator applied preprinted product ID labels by hand. The process was slow and inefficient, and Dow wanted to automate the entire operation.
Hairston was put in charge of the project, but he wanted to proceed with caution. "I'd never put in a drumming machine in my life. If it didn't work, my neck stuck out," he says.
He and his team did their homework ," including visiting manufacturing plants both here and in Europe to see systems in operation ," and in the end decided to get help from Dow's long-time business partner Feige Filling Technologies USA of Houston.
Feige has supplied filling technology to more than 20 other Dow facilities around the world, and the company's track record as an established fabricator of fully automated machines gave the team a sense of security.
"They came highly recommended," says Hairston.
Feige consolidated the six manual lines into two automated lines ," Line A and Line B ,"that operate side by side. Line A handles the nonhazardous chemicals and Line B the hazardous or flammable materials.
A photoelectric eye on the conveyor alerts the label applicator that drums are approaching and initiates the labeling process.
Sticky labels
Automating and consolidating the fill lines was only part of the job, however. Label application was another sticking point ," almost literally.
Much of the difficulty lies with the fact that labels come on backing paper, according to Holger Ferst, president of Feige Filling Technologies. Most of the time, the label is applied directly from the backing paper to the drum and, if the machine speed is not exactly right, the backing paper tears. The labels then are applied in the wrong place, or they also tear and make a mess, slowing down the production cycle.
Fortunately, Feige had experience with another client in Houston that had a problem similar to Dow's. For the solution, the company went to label-maker Avery Dennison.
Avery Dennison developed a new way to apply the labels that prevents backing tears. The Avery Dennison system separates the label from the backing paper before the two of them reach the drum. Then it holds the label in place on a vacuum head, from where it is applied directly to the drum. The backing paper never comes into contact with the drum at all.
Feige shared with Dow its experience with Avery Dennison. Hairston and his team saw the system in operation at another plant and, working collaboratively with Feige and Avery Dennison, developed a labeling system that solved Dow's own labeling problem.
Two challenges
Dow had two additional concerns about the labelers. First, the labeling system had to be integrated into the plant workflow so the right labels ended up on the right drums. The labelers, therefore, were set up to apply the preprinted labels to filled drums.
The other challenge for Avery Dennison was to set up the labelers to hit the target location on the filled drums. This setup was complicated by the fact that Dow has an elevated floor in the filling area. Avery Dennison had to structure and position its mounting devices below the floor level to get the positioning right.
Dow Chemical's new automated drum-filling system.
The Feige drum-handling equipment now fills and seals the drums automatically, one drum at a time. Then conveyors transfer the filled drums to the label applicators. A photoelectric eye on the conveyor alerts the label applicators the drums are approaching and initiates the labeling process. Three Avery Dennison ALS Series label applicators ," two for Line B and one for Line A ," are part of the system. The hazardous materials line need two labelers because those drums require both a product and a hazardous material label.
Thanks to a collaborative effort and clear communication, Dow now is reaping the benefits of the new system. Hairston says the system has led to a "substantial increase in efficiency." He adds: "Labor requirements related to drum filling, handling and labeling have been substantially reduced. Also, the automatic label applicators have lessened the risk of drum mislabeling."
For more information about Feige Filling Technologies Select 495, Avery Dennison Select 494 at www.chemicalprocessing.com/cp/reader_service.
