Laser Welding Increases Capabilities, Improves Surface Quality
“The finishes are consistent and meet the requirements of our customers. They want less labor and expenses for clean-up and revenue as well as the ability to save certain parts that would normally have to be replaced due to heat transfer.”
Hi-Tech Welding (Lee’s Summit, MO)—a full-service welding and fabrication shop—provides services like precision tool and die welding, laser and microscopic welding, custom sheet metal fabrication, structural fabrication, plasma cutting, water jet cutting and repair work. The company chose the HTS 200 from O.R. Laser USA (Elk Grove Village, IL) to maintain 100 percent accurate finishes on its tool and die work.
According to Hi-Tech Welding Laser/Tool and Die Welder Rob Lynn, the approach to each job is critical “Our number-one factor to our approach is what the customer wants,” Lynn states, “including no sink from the weld where there is less material stock left on the part. The HTS 200’s accuracy is 100 percent. The finishes are consistent and meet the requirements of our customers. They want less labor and expenses for cleanup and more revenue as well as the ability to save certain parts that would normally have to be replaced due to heat transfer.”
The company chose laser welding over TIG and MIG processes because laser welding results in a better finished quality product with less cleanup since the welder can pinpoint areas needing weld and there is minimal heat sink for blending. Lynn also notes fixturing is extremely important and specific to laser welding to hold the parts and allow the welder to focus on the part through the microscope in a more stable environment.
According to O.R. Laser USA Vice President Uri Resnik, the HTS series of Laser Welding Systems by OR Laser has gone through a number of upgrades over the years since the introduction to the market in 1998. “The HTS B is the latest version of the revolutionary laser system and remains the most versatile laser welding system on the market due to its open design and mobility,” Resnik states. “Designed for comfort for the operator and versatility of the job place, this system has no weight or size limit with regards to the mold.
Resnik notes that the design of the machine allows the laser arm to be moved on a 180-degree radius around the mold—allowing the operator faster set-up time in between molds and tools of different sizes, while still holding the integrity of precise positioning without any vibration to the microscope, laser head or laser delivery. “The system also features a standard X/Y/Z joystick for movement—making it easy for the operator to handle and thus faster processing time,” he comments.
The HTS B also has an easy-to-use touch screen for laser parameter settings, pre-sets that are programmable and retrievable with a built-in digital maintenance log to keep track of laser hours and assistance with the user’s/company’s preventative maintenance plan.
Laser welding, Resnik continues, repairs surface cracks, edges, corners, damaged gates and worn sealing edges with minimal adverse effects to surrounding textured or polished areas due to the localized heat—and offers numerous advantages to the moldmaker. First, the work area is easily viewed through the microscope. “Depending on the lenses used, your target spot may be 4 to 12 inches from the lens with only the wire (electrode) in the vision field, so your welding area is more exposed,” he explains. “With the controlling of peak power, pulse duration, pulse time and traverse movement, the laser gives you unsurpassed control of the welding. Using tool steels, stainless steels or aluminums in a diameter of wire as small as .008 inch, the welding area is extremely precise. You can put down the exact amount of material, exactly where you want it.”
The area to be repaired may be filled in several operational phases. “With each phase, new material from the filler rods is applied until the final desired surface height is reached,” Resnik states. “Fusion occurs by focusing the laser beam on the surface. This creates a metallurgical bond between the base and layer materials, which occurs due to the fusing of base material in a thin boundary layer. The composition fulfills the metallurgical characteristics for mechanical, chemical and thermal stress. With an extremely short application of energy (about 7 milliseconds) we are able to prevent the transfer of heat to areas outside the welding point.”
Additionally, once the operator has been taught the process and the system’s capabilities by an O.R. Laser technician, the laser welding process allows for mechanized precision, low post work clean-up and no pre-heating or post-heat treating of the molds—allowing the welder to work at room temperature with cooler substrate material for an improved work environment and a quicker, easier job, Resnik adds.
Lynn notes that the HTS 200 is very helpful with deep small pockets on certain parts. “It allows you to get to these areas without having to machine out bigger pockets to clear the welding torch,” he says. “The laser will reach these areas and keep good gas coverage.”
While Lynn says there was a learning curve with laser welding technology compared to TIG and MIG welding that involves getting used to looking through a microscope, he notes that O.R. Laser provided an on-site demo and training. “Working under a microscope has its benefits,” he comments. “You can see what you are welding a lot better. The demo was good to introduce us to the process, and I am constantly learning something new. Don’t be afraid to make mistakes. It may happen at first, but trust the machine and you will master the process.”
“This state-of-the art technology allows us to offer our customers a wider range of welding capabilities,” Lynn concludes, “which resulted in an increase in knowledge—and revenue—for us.”
Hi-Tech Welding / (816) 525-6618
email@example.com / hi-tech-welding.com
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