The Fabricator - Sample Issue

Subharmonic vibration technology helps fabricator solve distortion problems

Situation

Peninsula Metal Fabrication, San Jose, Calif., manufactures advanced precision assemblies, with expertise in welding frames, chassis, and sheet metal.

The company recently received a request to quote some new business and discovered that the request for proposal specified vibratory stress relieving during the welding process.

Peninsula did not have a current system to provide this type of stress relief. On occasion the company sent out parts to be heat-treated, but that process was time-intensive and expensive and did not occur during the welding process.

In addition, the company was having problems with distortion control.

“We’re a large frame manufacturer and the bulk of our work is stainless steel,” explained Paul Eischens, weld manager of Peninsula Metal Fabrication. “We tend to get a lot of distortion and squareness issues.”

Resolution

To be eligible for the quoting process, the company called Bonal Technologies Inc. to test its Pulse Puddle Arc Welding^®(PPAW) unit.

The technology uses a subharmonic vibration technology to provide vibratory stress relief during the welding process.

It creates a pulsating weld puddle while the liquid metal is deposited. The process allows for an optimum energy level to pulsate the weld puddle, which in turn creates a finer weld grain structure and a homogeneous mix with few columnar structures. Fewer columnar structures helps improve the weld metal’s mechanical properties by making the metal more ductile (up to 400 percent) while increasing its impact strength up to 75 percent, resulting in better crack resistance.

“The quality of our welds is so much better, it is like night and day,” said Eischens. “We have less straight-

ening time after the weld because the frame is stress-relieved while welding. We have 15 to 20 percent faster welds because of the better penetration.”

With the increased weld speed, the company also reduced overtime by 10 percent to 15 percent and decreased production costs by 2 percent to 3 percent per frame.

In addition, the cost to outsource heat treating has been eliminated.

The technology also allowed Peninsula to cut down on chamfering and grinding of the base metal and still get the same amount of weld penetration.

Bonal Technologies Inc., 1300 N. Campbell Road, Royal Oak, MI 48067, 248-582-0900, info@bonal.com, www. bonal.com

Tube fabricator uses ultrasonics for parts cleaning

Situation

For many manufacturers parts cleaning traditionally calls for dedicated labor and toxic solvents, which often require special handling and disposal. Eaton Aerospace of Jackson, Mich., was no different.

The company produces stainless steel, carbon steel, and titanium tubing for conveying air, oil, water, and coolant in aircraft and marine vehicles. Straight tubing arrives at the factory in diameters from 0.75 in. to 3 in., and then the tubing is fabricated into

complex shapes. Tube sections are cut to length and bent with lubricated mandrels, which are inserted into tubes to prevent kinking. After the tubes are bent, oils and tube bending lubricants must be removed.

“People are fussy about how their tubes look,” said Bud Greener, Eaton Aerospace’s manufacturing engineer. A clean, well-fabricated product is needed to meet manufacturers ’ tough quality standards.

For many years Greener and his team cleaned tubing with mineral spirits and Stoddard solvent, a petroleum mixture that requires special storage, usage, and disposal. The company wanted a more cost-effective and environmentally friendly parts-cleaning process.

“Prior to the ultrasonic systems, we cleaned tubes manually. Now we put them into the cleaning systems, adjust the settings, and walk away to do something else while the parts are being cleaned,” Greener said.

Resolution

At the WESTEC tradeshow, Greener and his supervisor discovered ultrasound products. Impressed by what they saw, they commissioned Omegasonics to retrofit two 300-gal. tanks for ultrasonic cleaning of tubing. Omegasonics also supplied generators and other components, as well as floor model machines.

Eaton Aerospace’s tanks use specialized, environmentally friendly cleaning solutions, heat, water, and ultrasonic sound waves for cleaning. Not only has the tube fabricator experienced labor savings with the new cleaning approach, it also has found that the system does a more effective cleaning job because of the liquid’s cavitation properties. It can reach areas human hands and other devices can’t reach.