But how often our perception is deceiving. For example, you are traveling in an unfamiliar city when you become hungry. As you search for a restaurant, what factors do you consider before entering? Perhaps you quickly evaluate the cleanliness of the building's exterior or how busy the establishment appears to be. What price range the décor indicates might be another factor. Yet after all these judgements calls, do you really know how good the food is or what sort of service you will receive by that which you see from the outside? It is our perception of a given situation that often dictates our response. Frequently though, perception is wholly different from reality.

So how does this apply to the quality of springs? Well, if a spring manufacturing facility discovered that the quality of one of its parts was substandard, what areas of the production line would generally be focused upon in determining the problem? Where would you look? First, perhaps the coiler and the tooling. Second, the supplied wire package and its consistency. Then, then maybe the straightener. The normal perception is that these particular factors are the only ones that matter to the maintenance and improvement of spring quality. So what is the problem?

The wire dereeler has often been viewed as having no positive effect on production quality. Unfortunately, payoff performance is often based only on whether the bearing on the "Lazy Susan" is still allowing the table to turn. Although more and more companies are beginning to see the benefits of working with powered dereelers, most still seem to perceive that this kind of equipment has little to do with quality assurance. The wire dereeler is usually the last place one looks when striving for quality excellence.

Should this be so? Is there any reason to consider the constant tension dereeler available today? Are they a viable means of increasing spring quality? Consider the following case history.

Spring quality is essential to the performance of a windshield wiper blade. If the "load" is insufficient, the blade will not have enough pressure to maintain contact with the windshield. Conversely, if the spring exerts too much force on the wiper's "arm," the blade will drag across the windshield and cause "chatter." It is therefore imperative that the springs utilized in these wiper blades are products made with stringent quality control.

Approximately six years ago, Trico decided to look into methods of improving production efficiency, as well as the level of quality in the spring department. Management was sure that there had to be a more productive, quality-orientated means of dereeling their wire than the usual methods of cutting 20 to 40 pounds of wire off the carrier and then running the material on a non-power swift. As they searched for new methods of wire decoiling, they discovered Accra-Wire Controls (AWC).

Carl Dischner, Spring Department Supervisor, related, "Accra-Wire seemed to provide the best overall package for our needs. The machines were innovative and the technology was better than we had seen in any other payoff. The service they offered, along with the affordability of the machines, made the decision clear for us."

Trico decided to try its first Accra-Botic dereeler, like the one shown in at right, in 1990. The results were better than expected.

"The dereeler's ability to maintain a constant low tension on the wire was the key to our quality improvement," continued Dischner. "With our old reels, the wire would be pulled forcefully by the feed and then go slack. The constant inconstancy was causing variances in our free lengths as well as our load deflection."

Constant tension is a necessary for proper decoiling of wire. As noted with non-powered (and even many powered dereelers) wire tension is not constant. This factor hinders the feed's ability to maintain consistent feed lengths. In fact, according to Don Senko, Quality Manager at Trico, the company attained 62% improvement in free lengths and an 85% improvement in load deflection consistency by adding constant tension dereelers.

Senko explained, "The extension spring with a formed hook on each end is our primary type of spring. In our application, correct alignment, of the hook ends is important since, if out of alignment, it will place undue torque at the point of force thus neutralizing the desired effect."

How did the new wire dereeler affect this particular aspect of quality control? Senko continued, "The automatic (constant tension) wire payoffs allowed us to achieve greater accuracy, reduced variability, and reduced costs since we were able to control the positions of the hooks and maintain uniformity in the back pitch."

The Cpk Index Graph below illustrates improvement in quality for four Trico parts as a result of installing automatic constant tension wire payoffs.



Additional benefits were realized in the area of increased production efficiency. By using these payoffs, Trico found that it had the capability to place the entire carrier of wire on the dereeler. With that arrangement, coiler downtime was minimized. As a matter of fact, a single package of wire containing four shifts' worth of process material is now loaded onto each of the company's 16 AWC constant tension dereelers.

Moreover, labor savings were realized. "We used to have six people sorting springs to ensure quality," Senko said. "Because of the consistent quality we now maintain, we need only one person."

Overall, Trico has reduced labor cost by 60% to 80% in the spring department. Another area of savings involves maintenance. According to Senko, the company has seen a 40% to 70% reduction in tooling maintenance since installing the new dereelers.

In the analysis, Trico has increased its ability to cost effectively produce quality springs. The simplicity of this new arrangement has reduced labor costs and scrap, increased production, and enhanced quality.