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From Powder and Bulk Dot Com Conveying
Coating process hinges on feed accuracy The process, developed by Anchor in the 1960s, requires that the powder be precisely metered into the fluidized bed. Precise metering ensures that the coating is uniforrn and is without holes and voids. The success of the coating operation depends in large part on the accuracy of the feeding process. Because the feeder is such a critical component of its operation, Anchor evaluated its production needs and operating conditions deliberately before beginning to solicit bids from feeder manufacturers. As a result of its evaluation, the company decided that in addition to providing feed accuracy, the volumetric feeder it purchased would have to be able to run essentially unattended for two shifts a day. The company then established other criteria that it used in selecting a dry solids feeder:
The feeder design had to be rugged because the life expectancy of the coating line, even under these extreme environmental conditions, was in excess of 10 years. To be considered, a feeder manufacturer had to prove that its equipment was running successfully in plants that had similar or even harsher conditions than Anchor's. The feeder had to have low life cycle costs, demonstrated by good repair history and reasonably priced spare parts. After soliciting bids from several manufacturers, Anchor decided to order from a relatively young company whose feeder offered the accuracy and low life cycle costs that Anchor required. In addition, the manufacturer had experience with operations even more demanding than Anchor's, and its stainless steel equipment had performed well in those situations. The Model 105, the machine chosen, uses a dual auger system in which the larger auger (intromitter) rotates around the smaller metering auger at a proportionately slower speed. It continuously conditions the product to a uniform bulk density while simultaneously and efficiently filling the smaller auger from a full 360 degrees. The conditioning of the powder improves the accuracy of the feed. Performance exceeds expectations In 1967, Anchor ordered five Model 105 volumetric feeders. Since then, the feeders have operated an average of 100 hours a week, 52 weeks a year. The total estimated operating hours for each machine is more than 100,000, and after 23 years they continue to meter PVC vinyl powder accurately and reliably. During this period Anchor Fence has had to replace only one part on one machine. The spare parts bill since 1967 totals $114.50, the cost of replacing a worn intromitter drive shaft. The part was shipped from stock within 24 hours after it was ordered. In the opinion of Andrew Schwarz, Anchor's director of purchasing, the engineer who specified and selected the feeders knew what he was doing: "I was with Anchor back when the feeders were purchased, but I wasn't in purchasing," Schwarz said. "I know the engineer who chose them was a stickler for reliability and ruggedness. Looking back now, with 23 years of performance, I'd say he made the right choice. They're working as well today as they did back then." For more information contact: Acrison, Inc. 20 Empire Blvd. Moonachie, NJ 07074 Telephone: 201-440-8300 Fax: 201-440-4939 Email: informail@acrison.com Website: http://www.acrison.com/ © Copyright 1998 - 2008 Powder and Bulk Dot Com |
