Machining area of the ELC 160 laser welding machine for welding gears: The gear is heated, joined and laser-welded at up to three stations.
Laser welding a synchronizer to a gear costs less due to the new fiber laser in the ELC 160, according to the company.
Laser-welded gear
The ELC 250 DUO is a compact laser production center for machining differential housings. The duo version of the ELC has twin spindles. "This two-station mode allows the working spindles to be loaded and unloaded during the machining time," said a company spokesperson.
Laser welding the balancing gearbox housing and the ring gear has allowed the component weight to be reduced by 1.2 kg.
"Even a few years back, major manufacturers utilized standard CO2 lasers in factories for welding applications," said an EMAG spokesperson. "Massive systems installed in separate rooms away from the actual production process supplied the energy for what, at the time, was relatively new laser welding technology. Developments since then have continued, and modern systems increasingly use solid-state lasers which deliver a major range of benefits."
"In 2008, we started to use solid-state lasers on our systems because the benefits they deliver compared to the established CO2 lasers are overwhelming," said Dr. Andreas Mootz, CEO of EMAG Automation GmbH. "EMAG Lasertec, who works with laser technology daily, pioneered the use of solid lasers for welding precision parts such as gearbox components. The requirements on the system and process technology and the requirements for clamping and equipment are much higher than with the CO2 laser."
The company suggests that the user focus on two components of laser welding system costs: the energy consumption of the laser and the cost of the gas, distinguished between the laser gas (laser medium) and the shielding gas for stabilizing the welding process. "In addition to gas consumption, expensive gas logistics cause costs to increase," said the spokesperson. "These are simply eliminated by using solid-state, such as a disk or fiber, laser. Most applications on EMAG systems use compressed air as they process gas, which does not affect the quality of the weld, although it creates a thin oxide coating on its surface.
"The CO2 laser also cannot compete with the solid-state laser in terms of energy consumption. 56 kW of electric current is used by a CO2 laser to generate a laser capacity of 4 kW, while a solid-state laser requires just 17 kW, an energy savings of 70%. In addition, a solid laser requires much less cooling. Added together, a solid-state laser consumes roughly one-quarter the energy of a CO2 laser."
Laser welding systems often operate with short cycle times, often a few seconds, facilitating and enhancing the part throughput rate. Their integration into the material flow within the production process is therefore an important factor. On CO2 laser systems, the beam is guided to the welding lens by mirror systems. The beam source, cooling units and machining station(s) must therefore be close together. "This results in a series of drawbacks, such as the complicated feed and discharge of the parts for welding, which makes supplying several welding stations with the same laser source a challenge," said the spokesperson. "In practice, these problems do not exist when using disk or fiber laser welding systems since the space requirement is so low that they can be easily integrated into existing production lines. The actual laser source may be up to 50 meters from the system, as the beam can be guided with relative ease due to the transport fibers allowing the welding stations to be perfectly integrated into the material flow.
"Falling costs and a better system layout are benefits, however meaningless if the quality of the weld does not match that produced by a CO2 laser. Not only is this the case, but welding speed can even be increased in many applications. This reduces both heat warping in the workpiece and the cycle time. More efficient lasers with faster welding speeds through the use of fiber or disk lasers make them ideal to meet current demands of component production for fuel-saving and lightweight motor vehicles."
"We cannot say that there are any drawbacks compared to the use of CO2 lasers, rather challenges in the process that must be overcome," said Dr. Mootz. "For example, the use of solid lasers makes for much greater precision than in the past. A beam position accuracy of less than 50 um places heavy demands on the machine, workpiece holders and clamping devices, as well as on the focus and alignment of the laser's lens." According to the spokesperson, EMAG ELC systems satisfy these demands.
"If, for example, the increase of weld spatter through the use of solid-state lasers is considered, perfectly tailored tools to fully cover the component are developed," said the spokesperson. "For machining different components this raises the question of retooling times, for which EMAG has found an efficient solution on the ELC 160. The system features a tool bridge with up to three different tool sets in addition to an integrated flue gas extractor, which allows retooling to be carried out in a matter of seconds and is ideal for the flexible and productive manufacture of gearbox parts in large volumes.
"We have found that there is practically no alternative to the use of solid-state lasers on production laser welding systems for the manufacture of powertrain components. Nevertheless, their use requires extensive expertise to bundle the benefits in an efficient laser system such as the ELC series systems from EMAG."
For more information contact:
Peter Loetzner
EMAG LLC
38800 Grand River Avenue
Farmington Hills, MI 48335
248-477-7440
info@usa.emag.com
www.emag.com
Southwest
AR
David Fitzgerald
EMAG LLC
248-595-1117
www.emag.com
TX, OK, LA
Ric Lorilla
EMAG LLC
248-595-1530
rlorilla@emag.com
Southeast
VA, NC, SC, GA, FL, TN, AL, MS
David Fitzgerald
EMAG LLC
248-595-1117
www.emag.com
Northeast
PA, NY
Kirk Stewart
EMAG LLC
248-996-4703
kstewart@emag.com
ME, NH, VT, MA, RI, CT, NJ, DE, MD
Jonathan Chomicz
EMAG LLC
248-497-8526
jchomicz@emag.com
WV
David Fitzgerald
EMAG LLC
248-595-1117
www.emag.com
Midwest
IN, MI, OH
Kirk Stewart
EMAG LLC
248-996-4703
kstewart@emag.com
ND, MN, WI, SD, NE, KS, IA, MO, IL
Tod Petrik
EMAG LLC
248-470-2646
tpetrik@emag.com
KY
David Fitzgerald
EMAG LLC
248-595-1117
www.emag.com
West
Peter Loetzner
248-477-7440
info@usa.emag.com
Arnie Sugiyama
Caltec International
19801 Hamilton Ave
Torrance, CA 90502
310-527-4110
arnie@caltecusa.com