Advertising in MoldMaking Technology offers
Issue link: https://mmt.epubxp.com/i/498250
moldmakingtechnology.com 21 Within a few years after the company's founding, however, Mourouzis and his team realized that TIG and micro-TIG would no longer be enough. In 2006, the company purchased its first laser system, a 1900 series machine from Riverside, Rhode Island-based LaserStar Technologies. Subsequent years would see the shop further expand laser capacity with the addition of larger, more automated models, such as LaserStar's 7700 series. Today, laser equipment is employed for approximately 35 percent of all work at Wicked Welding, and all indi- cations are that this figure will con- tinue to increase, Mourouzis says. An Essential Process Whether for repairing worn areas, accommodating engineering changes or fixing mistakes, laser enables mold adjustments that would be either impossible or far more difficult with other welding technologies, he explains. That's primarily due to the processes' extreme precision. Wicked Welding's 7700 series machine, for instance, can lay beads as small as 0.0025 inch. That precision, in turn, can be credited large- ly to a second benefit of laser welding: minimal transfer of heat to the sur- rounding workpiece material. In contrast to the light emitted by a pulsed, ND:Yag laser, TIG and micro- TIG processes use electric current to create the heat needed to bind the filler rod to the workpiece material. The problem is that this current imparts comparatively more heat into the areas surrounding the weld, Mourouzis says. These areas of the workpiece can dis- tort, resulting in a phenomenon com- monly known as "sink." Compensating for this distortion often requires additional welding, which, in turn, leads to additional time spent remov- ing extra material via hand-grinding or even milling. In addition to saving time on these operations, minimal heat radiation often eliminates the need to preheat tool steel, a step that's often required to prevent TIG processes from cracking the work. Wicked Welding's largest, most pow- erful laser, the 7700 series machine, offers beam-enhancement resonator technology that is said to amplify these benefits. Known as Soft Touch, this feature is designed to limit thermal lensing, or the tendency of the center of a laser beam to be hotter than the outer regions. Soft Touch creates a softer, more uniform beam profile to avoid the resulting splashed metal, blown holes or damage to heat-sensitive material. This technology contributes to Wicked Welding's ability to keep sink to only about two tenths (0.0002 inch) in laser welding applications,