Reprinted from Appliance, October 1997 UNDER THE GUN
By Dan Davis, Associate Editor
Hannover hôtelsPowder suppliers and equipment makers are assisting appliance makers in their battle to decrease costs associated with powder coating operations. Catholic or Protestant. Jewish or Muslim. No matter what religion, evolutionists are prevalent in the appliance industry.
However, these believers are less concerned with some elongated history of an invertebrate's struggle to develop thumbs and more concerned with the evolution of technology. It's not a faith issue; it's a financial issue.
| Take powder coating, for instance. Twenty years ago, industry executives looked to powder coating as an exciting replacement for porcelain. After enjoying years of high-volume growth as another finishing option, powder coating suppliers targeted liquid finishing systems that ran afoul of the Environmental Protection Agency's guidelines. As more appliance makers installed powder coating operations, the quality reputation of the material blossomed. Now, the evolution revolves around economic solutions. Jim Munford, a quality engineer at GE's Appliance Park, is a faithful follower of fiscal fitness. As one of his biggest Six Sigma products, Mr. Munford took another look at the method in which they were finishing refrigerator doors. |  Powder Delivery Control Unit (PDC) - A device for the accurate and repeatable control of powder outputs |
Prior to its recent equipment investment, the finishing team used a Venturi-pump system with manual air-pressure controls.
"You are kind of guessing what you are putting on," Mr. Munford tells APPLIANCE Magazine. "You put it on, then you go measure. We really had no control over gun outputs-grams per minute of powder."
By controlling the material, you can better control costs, according to Mr. Munford.
Blogna Accommodation"That's what it's all about," he says.
hoteles ReimsTo help him do just that, representatives of ITW Gema introduced GE's finishing team to its Powder Delivery Control (PDC) unit, a PLC-controlled auger mechanism that is designed to deliver a precise amount of powder to the gun in a repeatable fashion.
| An auger mechanism provides precise regulation of powder delivery to the pump to reduce powder usage and improve coverage consistency | Mechelen luxury hotelsWhen the gun is triggered, an auger screw is engaged simultaneously, delivering powder into the inverted pump's throat. Once the powder is in the pump, the conveying air transfers the powder to the gun. This method reportedly provides less compressed air usage, reduced wear on parts, softer spray patterns, and reduced impact fusion. Most importantly, it is said to deliver within +/-1 percent of the desired output. The technology so impressed the GE engineers that they ordered 18 guns with a PDC unit, which accompanied an order for another 10 guns that will be used strictly for reinforcement. |
Mr. Munford estimates that the appliance maker will experience a savings of 15-25 percent once the equipment is in place. (The changeover to the new finishing system was expected to be completed sometime in January.)
When ITW Gema approached Whirlpool's Clyde (OH) Division about the PDC unit, the appliance engineers initially asked, "What type of improvements can we expect?"
"We are always looking for continuous improvement in the powder coat process," says Whirlpool's Troy Blodgett, a manufacturing engineer, "especially projects that may result in cost improvements."
After a trial period, the Whirlpool engineers were sold. They purchased the PDC unit, which controls the guns that finish the tops and lids of washing machines, and placed an order for another unit. Mr. Blodgett estimates Whirlpool has saved 10-15 percent in material usage since the unit's installation.
Not Yet Finished
Powder coating technology has made an indelible imprint on manufacturing. Over the past decade, powder coating has eliminated the use of solvents, the need to maintain viscosity balance, and the need for flash-off time requirements in many factories. It has also minimized touch-up operations and rejects.
But the job is not yet complete. Work still must be done to maximize first-pass transfer efficiency and material control. Appliance makers and their powder coating suppliers remain under the gun to deliver these cost- effective advancements.
