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Neatness counts

April 1, 2002
DeWys Manufacturing Inc., a Marne, Mich.-based custom precision sheetmetal fabrication company had splatter problems when MIG-welding thin-gage hydraulic reservoirs. Removing the splatter added about a minute in cleanup time to each part, totaling an extr

The System 40 welding cell at DeWys combines a Lincoln welding power source with a Fanuc Arc Mate 100i robot.

DeWys Manufacturing Inc., a Marne, Mich.-based custom precision sheetmetal fabrication company had splatter problems when MIG-welding thin-gage hydraulic reservoirs. Removing the splatter added about a minute in cleanup time to each part, totaling an extra 25 hr/week for the 1,500 parts produced. In addition, using a grinder to clean the weld splatter created dust and debris that contaminated the reservoir's pump. Therefore, DeWys needed a new way to weld.

After some research, DeWys sent 20 of its hydraulic reservoir parts to Lincoln Electric to test a robotic welding cell. "After Lincoln set up our sample, it demonstrated how the System 40 welded the reservoirs. Not only was the quality of the weld excellent, but, more importantly the splatter was eliminated and so was the cleaning time," says Chris Hawkins, team facilitator for DeWys. "What made this cell different was its Surface Tension Transfer (STT) power source, which is known for its capabilities to weld thin material without splatter."

The robotic cell's STT power source has a high-frequency inverter with advanced waveform control that cuts down on splatter and smoke during welding. The STT controls electrode current during the entire gas-metal-arc welding process, which lets the user control heat input independent of wire feed and speeds, especially on thin materials.

The System 40 combines the STT with a Fanuc Arc Mate 100i, 6-axis robot. The result is an easy-to-install, drop-in-place, plug-in workstation. The system's small footprint, which is forklift compatible, lets users easily move the robot when necessary.

DeWys' robot has two identical sets of tooling, each holding three, 12-gage HRPO parts that are welded to form one hydraulic reservoir. Because the tooling is mounted on a high-speed 180°-indexing table, operators unload and load parts while the robot is welding the next reservoir. Each reservoir requires 10 fillet welds, which the robot completes in 5 min.

In addition, DeWys' robotic cell includes Lincoln's 0.035-in. SuperArc L-56 MIG wire and a shielding gas of 90% argon and 10% CO2 that further minimizes spatter.The cell also has a number of safety features, such as steel barriers, to protect against flash and unauthorized entry. A flash screen separates the operator from the welding area, while safety door inter-locks and a readily accessible palm button for quick cycling add to the cell's safety.

Another benefit of the system is its TorchMate feature, which calibrates the robot in 15 sec. According to Hawkins, other robots at DeWys take up to 15 min to calibrate. And if the torch has a collision, the Torch-Mate's breakaway function eliminates having to replace the entire torch.

Service, says Hawkins, is also important. "One of the main reasons we chose Lincoln was the service, support, and reliability. Our older-model robots don't have the support behind them, which is a real problem. Our Lincoln sales representative, Bruce Chantry, was here during our entire installation process and continues to be on call whenever we need him." Lincoln also provided a training course on programming the robots.

The Lincoln Electric Co.
Cleveland
www.lincolnelectric.com