Metal Mates of Waterford, Michigan, has achieved certification to the new ISO 9001:2000 standards in November 2002, one year ahead of the deadline of December 15, 2003! Our continued commitment to customer satisfaction has been the foundation for this accomplishment.

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Ford engineers initially were attracted to the product's welding characteristics. Significant reductions in smoke and improvements in weld quality allowed this facility to bypass an expensive wash operation before welding. Tool and die engineers also noticed dramatic reductions in die wear in critical areas, such as the radii of severe flange forms. For more detailed information, refer to Lubricant Technologies, Vol. 1, February, 1998.

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In early 2002, a truck frame manufacturing plant had a new launch for 70 new sets of dies. The company knew that staying with the current processes of washing each part prior to welding was expensive and time consuming. The facility used two soluble oil stamping lubricants that had to be washed (sometimes twice). Management needed to implement a program that would eliminate the parts washer. Their first target was selecting a lubricant that would meet the forming needs of high strength steel and it's ability to weld through.

Additionally, the stamping department was interested in improving their environment. The current process used two five-stage/1500 gallon capacity washers, the first three stations were heated at 160º F with water and 7% concentration of a caustic cleaner solution in order to remove the oil from their stamped parts. The fourth station was an ambient water rinse, and the fifth, a rust inhibitor was applied. Due to the excessive oil contamination in the washers, the cleaning tanks become stagnant, rancid with bacteria and unbearable to work around. Workers that stacked the parts exiting the washer wore masks and operators needed aprons and gloves feeding oily parts into the washer. The cleaning tanks had to be dumped once a week and the waste hauled away. Tool and die makers complained of itchy rashes on forearms from working around dies with this soluble oil stamping lubricant. Also noted, the nitro-cylinders, punches and internal die sections were prone to rust in storage.

Selecting a lubricant through weld trials
Management selected five lubricant manufactures to perform preliminary MIG weld/smoke analysis. The weld/smoke test would narrow down to two companies. The part selected to examine the welds was the control arm, because of its full perimeter welding. In the lab welding engineers examined the weld penetration by crosscuts and carbon residual around each weld. Again narrowing down to one company's product for further testing and evaluation in forming. The lubricant selected was Metal Mates new HDP, which performed the best for lowest in smoke and best in weld penetration without porosity. After two months no rust was noticed around the welds.

Die Performance
Several new dies were selected for performance tests with Metal Mates HDP Stamping Lubricant. The goal was to keep scoring from occurring on the .250th to .400th gauge high strength steel parts. The one-week test run had found the Metal Mates conditioned the dies with no scoring and could be diluted to 3:1 where most the other lubricants could only run parts at 1:1 dilution. Dies ran cooler and no metal built up in the dies because the lubricant acted like a soap washing out the metal fines.

Two Week Trial in Welding
The Manufacturing, Welding Engineers and Production Departments evaluated HDP's test results together, and decided to use the Metal Mates HDP in production for two weeks on ten different parts. After the parts were stamped with Metal Mates HDP diluted 2:1, they were stored inside for two weeks. The stamped parts were then sent through the welding cells without washing for feedback from welding operators at hand welding ladders and robotic weld cells. The welding operators did not see any more smoke with the Metal Mates non-washed parts versus the washed parts. The engineers noticed a more amiable smell from Metal Mates HDP non-washed parts in the weld cell areas, compared to the washed parts that gave off a rancid odor after welding.

Paint Compatibility
The next pre-screening for the lubricant was the cleaning and paint compatibility. With a new paint line being implemented, the pre-treating cleaners and paint suppliers acknowledged that changing from a soluble oil lubricant to a water-based lubricant would be easier to clean off and create less oil in the waste stream. In order to prove this, four baskets of parts (150 in each) were run, set aside for one, two and three-week storage intervals. The parts were cleaned and painted in a similar time frame and all the parts met their quality standards.

Two Months Trials
A press and ten new parts were dedicated to the lube trials. The Manufacturing Engineers monitored the Metal Mates for two months in tool performance, weld penetration and paint compatibility. The evaluation determined that the frame hangers, engine mounts and shock towers could all have washing eliminated for two additional months.

Washer Eliminated
After six months of extensive trials with HDP Stamping Lubricant, and proving that the washer was not needed, one 30' washer was eliminated. They removed the washer from the site and gained more floor space, which provided improved JIT to their assembly plant for the first time. Additional benefits were the elimination of the rancid odors in the stamping department and increased production time.

Validation & Application Improvement
Once these weld tests were validated over an eight month period by weld engineers and management, a full changeover on all parts was implemented using Metal Mates HDP Stamping Lubricant.

Metal Mates had a training seminar for operators and tool and die department for application of the lubricant to minimize waste. The press area improved application with grooved-rollers in the first stage and in-die sprayers further down the die progression to minimize lubricant amount and usage. This helped control the amount of lubricant per part and provided the lowest amount of smoke in welding. These types of meetings are now held every quarter for follow up and continuous improvement.

Cost Savings
Removal of one washer would create yearly savings of $120,000 by eliminating cleaners, gas, electricity, rust inhibitors, down stream waste and maintenance on the washers. Other savings included the handling and repackaging of parts, saving time in production by reducing scrap, inspecting the parts leave gloves cleaner, increasing glove usage, eliminating sticky-tacky oily messes on the floors, thus improving housekeeping and gaining more room for die storage.

Conclusion
This frame manufacturer was able to eliminate a washer and keep up with today's environmental needs. Through regimented trials and verification programs, conclusive results that a stamping lubricant could eliminate the washer and keep the welding integrity was key to their success. When gauging new parts with new tooling, high amounts of coining, over lap metal and scoring occur. Metal Mates recommended at the die development stages, a die conditioning process starts with the stamping lubricant at  concentrate or 1:1, and then gradually increase the dilution specific to where the metal needs to flow. Using an IR gun to localize the hot spot in the dies, and apply the lubricant where the specific hot spots are in the die, can help minimize the smoke in welding. Mill oil on incoming steel and hard water are two other elements to be considered. Excess pooling of mill oil can contribute to smoke and must be monitored from the steel mill.  Hard water was also found to be a factor when evaluating the weld penetration. Calcium in hard water would dry on the part and cause more failures for the arc weld start-up. To resolve this issue, a water conditioner was implemented.

The following flow chart displays the elimination of
the washing stage and storage bank area.

 
Body Mount Bracket Welded Without Wash
30-50 non-washed parts are being welded together to complete the frame.

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