Metal finishing cleans, coats ANAD's refurbished parts
August 16, 2012
ANNISTON ARMY DEPOT, Ala. -- If it is rebuilt, reworked or repaired on Anniston Army Depot, odds are the Metal Finishing Branch touches it.
There, parts are cleaned of any paint or oil that may be clinging to the surfaces then given a coating of chrome, zinc, phosphate, nickle or other substance.
"We chemically clean and sandblast parts down to the bare metal then apply a metal finish," said Greg Leach, chief of the Metal Finishing Branch. "We touch about 90 percent of the parts that come off the vehicles overhauled here."
Parts prepped for a fresh coat of paint receive phosphate coating, which acts as a primer, allowing paint to adhere better to the slick metal surface.
Manganese phosphate is applied to parts, such as brackets, that will be left bare, since it resists rust.
And then there are the metal coating processes.
Vats filled with liquid metal line the shop, many topped off with a layer of table tennis balls to keep down potentially dangerous vapors.
"Chrome plating is applied to parts expected to have a lot of wear," said Leach. "We build the part up, above standard, with the chrome."
Once parts receive their metal finish, the machine shop removes any rough edges and readies the part for reinsertion in a vehicle or engine.
Because the job may require an employee to handle blast media and chemicals, Leach said respirators, aprons and face shields are required in certain areas.
They also receive additional training for the material.
"Because we handle so many chemicals, Resource Conservation and Recovery Act training is essential, as is guidance on proper disposal of hazardous wastes."
One recent project has helped to reduce the dangers in the metal finishing area.
In 2011, the depot began a change from NPX, an acid-based paint stripper containing approximately 75 percent methylene chloride, to a new product, Aqua Strip. This project was recently recognized by the Alabama Wildlife Federation for air conservation.