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Emitters Send Rust Packing

May 10, 2007
This rust-free steel lamination came out of a shipping bin that included two Daubrite VCI corrosionpreventative emitters. Rust and corrosion that occurred during shipping resulted in a high discard rate of motor laminations at ...

This rust-free steel lamination came out of a shipping bin that included two Daubrite VCI corrosionpreventative emitters.

Rust and corrosion that occurred during shipping resulted in a high discard rate of motor laminations at a steel parts producing company.

Temperature swings, high humidity and unwanted moisture were costing a leading steel-parts producer money. The company often shipped wafer-thin golf-ball size pieces of steel from Kentucky to deep into Mexico via truck and railcar, and rust developed during the journey. The parts are critical components used in a variety of sealed motors, and the rust caused an unacceptably high discard rate for the company's motor laminations.

The company contacted Dave Neuer of Neutech Packaging Systems (www.neutechpackaging.com) for a solution to this expensive corrosion problem. He evaluated the company's practice of using eight moisture-absorbing desiccant packets in each container of parts shipped. "They were just tossing them into the returnable bins, so my first question was 'how did they know the desiccants didn't already have moisture in them?'" he said. This was a valid question because the company would re-use the packets, drying them out to save money. Neuer suggested a joint test to compare the currently used desiccant program with a new prototype style of Daubrite volatile corrosion inhibitor (VCI) emitter from a company called Daubert Cromwell (www.daubertcromwell.com) that specializes in anti-corrosion packaging.

For corrosion prevention inside package environments and enclosures, the 2-in.-round, flat VCI emitter disks from Daubert Cromwell dispense a vapor that forms an invisible protective layer on metal surfaces that wards off moisture, salt, dirt and oxygen, all of which can cause corrosion. The company said each disk protects 5 cubic-ft of enclosed space.

Neuer and Daubert Cromwell engineers together created an emitter disk within a porous gauze package that could be used as a desiccant, but works as a VCI. They placed two emitters in each shipping bin and ran a series of Kentucky-to-Mexico test runs. "The bins with the Daubert Cromwell emitters had the best results. And we determined that shipping steel laminations with the VCI emitters would save the steel parts company $0.80 per load, or $120 per day. That works out to $30,000 a year compared with the old shipping way," said Neuer. And these amounts did not include the savings resulting from throwing away fewer ruined laminations.

The steel-parts company now uses VCI emitters in the 150 pallets it ships each day, or about 10,000 every 50 days. The company has also phased in VCI emitter use to its other plants as well.