February 2009 - Mention lasers to most people outside the manufacturing industry and they’re likely to conjure up scenes from "Star Wars" or "Austin Powers." But these tools are no longer limited to the silver screen. The simplicity and accessibility associated with fiber lasers in particular are helping many companies redefine their manufacturing processes.
One example of fiber laser technology is a YLR 4000 ytterbium fiber laser from IPG Photonics Corp., Oxford, Mass. In addition to having high wall-plug electrical efficiency and taking up less floor space than conventional material processing lasers, the YLR 4000 can both cut and weld, says Bill Shiner, vice president of industrial lasers at IPG Photonics.
"What’s unique about the machine is that it has an integrated internal beam switch," he says. "You can switch from a cutting head to a welding head from the same laser, allowing you to do both welding and cutting from the same workstation. And more importantly, you can switch from one to the other on the fly."
The laser can be used on any metal, including low-carbon steel, stainless steel and aluminum, as well as many composites and some plastics. It can also operate in one of two modes.
"The unit laser is operated continuously or modulated, depending on what your application requirement is," says Shiner. "And because it’s diode-excited, the laser is extremely responsive. You can change power on the fly, switch to [continuous wave] operation or pulsed operation and can ramp the power up and down."
The YLR 4000 has been integrated into several recently delivered work cells by VIL Laser Systems, a subsidiary of Wayne Trail Technologies Inc., Fort Loramie, Ohio. One is the Flex Lase, a system that uses a "works-in-a-box" approach, according to Bob Lewinski, vice president of marketing and sales at Wayne Trail Technologies.
"In a Class 1 safety enclosure, on a structural platform, we package a six-axis robot with the proper end-of-arm mounted focus head, based on the process that it’s required to carry out," he says. "And the laser, chiller, robot controller and all the required devices you need to make that cell operational are all contained in this modular, easy-to-install system."
Industries that use the Flex Lase include automotive, aerospace, appliance, commercial aircraft and general hardware. IPG Photonics also uses the Flex Lase in its applications facilities both domestically and abroad.
"We think so highly of the machine, we’ve purchased some," says Shiner. "We purchased one for our plant in Russia and one for our plant here in Oxford, Mass., for doing application development for potential customers."
As a systems integrator, Wayne Trail Technologies uses a Flex Lase on-site for research and development. Lewinski says the company uses the machine to perform prototype and process development.
"Many customers have existing products they want to improve the quality on, perhaps improve the appearance or maybe improve the performance of the finished goods that they’re making," says Lewinski. "Or they’re also looking for ways to reduce costs with less material or different types of material while perhaps trying to replace a traditionally labor-intense process."
In regard to laser welding, many customers want to know whether they can use a laser to make a product that’s been made using spot welding or a mechanical fastening method, according to Lewinski. Others seek to determine whether it’s possible to deploy laser processes for a new or prototype product, whether it involves welding, cutting, cladding or even heat treating.
"At the end of the day, welding is welding," he says. "However, [what varies are] the tolerance of how things stack up and the ability to engineer the product better to make use of the laser, which has a very fine, focused spot of heat, resulting in a small heat-affected zone. Those are generally good metallurgical traits that can make the laser weld desirable, from an appearance, performance or even a structural standpoint. Or it enables welding or cutting of materials that otherwise, perhaps, wasn’t even possible."
Lewinski says the process begins similarly with laser cutting customers. The typical steps are to determine how to fixture the parts, how to optimize the use of the laser and how to implement a successful, workable process. The latter includes consideration of automation and safety requirements, which Lewinski describes as Wayne Trail Technologies’ forte.
"We’re always looking at the overall package," he says. "And the IPG system, being so compact, being so versatile in its range of uses and being so reliable, has become a great enabler to even more wide-ranging applications."
Additionally, Lewinski cites the machine’s ease of use, affordability and reliability as reasons more companies are turning to laser technology when they might not have done so before.
"The laser is there as a tool, but in the case of the IPG product, the laser doesn’t become the focal point of the application," he says. "You can now pay attention to the process, the fixtures, the materials--where all the attention should be paid. You don’t have to have a scientist, engineer or high-level tech as part of the team just to maintain or tweak the laser for normal operation. The fiber laser by IPG has allowed us to cross that threshold and bring this technology into the hands of many."
The YLR laser series is available in a range of power levels, and Wayne Trail Technologies decides the power requirements based on the work to be done in the time frame allotted, says Lewinski. The company creates systems that require a YLR 1000, which is a 1-kilowatt machine, up to the 6-kilowatt YLR 6000.
As of December, Wayne Trail Technologies had installed six fiber lasers and had orders for four more. The first YLR 4000 the company put in use wasn’t for a Flex Lase, though, but rather a tailored blank welding system called a Flex Weld.
This machine is at Toyotomi America Corp., Springfield, Ky., a domestic supplier for the automotive industry. The Flex Weld was installed about three years ago, and it has contributed to increases in efficiency and productivity, according to Lewinski.
"In this particular case, the customer was unable to produce the part required, so they were obligated to buy these laser-welded tailored blanks from other sources and then incorporate them into their stamped product," he says. "By purchasing our machine with this laser, they now make the laser-welded blanks in-house for a significant cost savings and a just-in-time availability. They can control their own quality much easier and at less expense than they could purchasing these blanks from outside sources."
Specifically, Toyotomi America uses the machine to weld pieces of steel into sunroof frames. A benefit for the busy company is that the Flex Weld has required minimal upkeep, says Keith Anderson, assistant manager of maintenance at Toyotomi America.
"On the laser welder, we’ve had no problems with it at all," he says. "Basically, you plug it in and forget about it. Other than keeping the water clean in the cooling system and doing routine maintenance, as far as ensuring everything is working properly, we haven’t had to do anything with it." MM