February 2010 - Al Foubert, tooling manager at National Auto Radiator Mfg. Co. Ltd., (part of The Narmco Group), Windsor, Ontario, had identified an opportunity for a process improvement and scrap reduction on a deep-drawn fuel tank cover.

Areas that were singled out for improvement were uptime, scrap reduction and the elimination of the wet lubricant that caused costly environmental waste disposal and undesirable work conditions.

The Narmco Group is a privately held, full-service company that supplies various automotive OEMs with engineered metal stampings, assemblies and tooling.

Founded in 1945 by Matthew Rodzik, Narmco has grown from its original company, National Auto Radiator Mfg. Co. Ltd., into a family of 11 companies throughout Canada and the United States.

Opportunity
Foubert describes the fuel tank cover as a "9-in., deep-drawn pan done in one hit, without a pre-draw."

From the beginning, Foubert and his team of experienced die-makers were forced to use plastic on the corners of the blank to allow the metal to draw.

A conventional heavy wet lubricant accompanied the draw, leading to several housekeeping challenges and a high operating cost.

"We ended up using more fluid than we would have liked to," says Foubert. "When we pumped it out of the pit, it had to go through a treatment plant as waste oil, and this cost exceeded $2 per liter for disposal."

Although the 0.09-in.-thick, 60-lb. galvanized steel fuel tank wasn’t a high-production job for Narmco, the company was still producing 1,100 per week with an operating cost well exceeding the target cost.

It was clear Foubert and his team needed to react to the problem with an idea that could eliminate all of the above costs.

Continuous improvement
Foubert looked into different ways to alleviate the part’s formability problems. One possible solution was the use of a dry-film lubricant that could be preprocessed on the coil.

With no coaters locally, Foubert found Chemcoaters LLC, Gary, Ind. Bill Krippes, technical manager at Chemcoaters, provided an interest in the problem at Narmco and offered a dry-film solution. Initially, Krippes offered Narmco the product Chemform as a possible solution.

Foubert sent Chemcoaters a coil, and it was determined to provide several possible remedies to the problem and then select the one that achieved the best results.

Chemcoaters coated half the coil with an alternative product and the other half with Chemform. Although the alternative dry-film product went through the stamping dies fine, Chemform was far superior, according to Foubert.

He gauged this by how many adjustments to the stamping tools were made when Narmco ran the alternative dry lube compared with the number of adjustments made after running the Chemform dry lube. "With the Chemform product, it ran superbly with just a few adjustments to the stamping equipment," says Foubert.

Dry-film benefits
For the fuel tank cover, Narmco’s scrap rate with the Chemform dry lubricant went to nearly zero, uptime was increased, manpower was reduced and housekeeping was enhanced.

Foubert also says the lubricity of the dry film allows him to reduce the tonnage of the stamping press.

"The steel runs well into the die, and it doesn’t wrinkle," he says.

Because of the results on the fuel tank cover, Foubert decided to expand the use of the dry-film product to two other deep-drawn pans.

With both products, Narmco was able to reduce costs by eliminating the use of die chrome maintenance on the die surface, as well as continue to eliminate its plant-operating expenses for waste treatment and improve the appearance of the overall plant.

Downstream in secondary operations, such as welding and painting, the dry-film lubricant presents no problems, according to Foubert.

"It’s an environmentally friendly lubricant," he says. "It’s water-soluble and washes off the part easily."

Also, the success of dry-film lubricant on deep-drawn pans has enabled Narmco to operate more competitively in an increasingly global market.

Coil coating
"Chemcoaters’ line is designed to be a low-cost applicator of dry-film lubes," says Krippes. "Therefore, our customers are able to afford these products and more easily take advantage of the benefits of dry-film lubrication."

On Chemcoaters’ dry-film lubrication line, the company can take a coil up to 72 in. wide and 72,000 lbs. ranging in thickness from 0.008 in. to 0.125 in.

Chemcoaters cleans off any oil film on the coil, applies the dry-film lube and then bakes it on using an infrared oven.

"These films are like applying an acrylic house paint but without the pigmentation, so they are clear," says Krippes. "Acrylic dry-film lubricants have a low coefficient of friction, ranging from 0.04 to 0.1, allowing them to form parts that are either difficult to form or can’t be formed using a wet lube. Because of their nature and hardness, dry lubes reduce or eliminate metal-to-metal contact, decreasing part galling and subsequent damage to dies. This results in less die maintenance, improved manufacturing efficiencies, minimized tool or part breakage and greater profitability. They also eliminate the need for oils, pre-lubes and drawing compounds." FFJ

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