The BLM LT-FREE High Flex uses twin robots and a dual moving part table handling system, including scrap collection
Above: The BLM LT-FREE High Flex for bent and hydroformed tubes, flat and deep-drawn sheets, or welded assemblies uses twin robots and a dual moving part table handling system, including scrap collection.
October 2018 - A typical tube bending process includes pre-bending and additional post-bend processing, such as miter cutting or adding holes and slots.
For tube and pipe fabricator Hydro Tube Enterprises, increasing capabilities while simplifying its processes required a capital investment in a fiber laser cutting machine. “We needed a multi-axis fiber tube laser with robotic loading,” says Tim Althaus, vice president of operations. “With the LT-FREE, we can handle the tube cutting without any pre-bend operations necessary. We can bend the tube and load it into the LT-FREE and bring the part out complete with holes and slots. We don’t have to go back and forth.”
Before purchasing the machine from BLM Group, Novi, Michigan, Hydro Tube operators spent considerable time bending and strategically placing holes into the tubing. Now, says Althaus, the company can produce parts quickly and accurately.
“Bending is still critical to the process, but the fiber laser makes adding slots or holes much easier,” adds Althaus. “In the past, we put features on our straight tube lasers and then took them back to the bending stations to manually [identify] hole locations and check that the twist angles were right. Now we can leave those holes out, speed up the bending process, and take the tube to the LT-FREE after bending to [drill] holes. Instead of a five-step process, we’ve cut it down to two steps.”
Smooth transitions
Reducing the preproduction time prior to moving the tubing to the machining area of the operation was crucial to the tube fabricator’s decision to select the LT-FREE from BLM Group. Hydro Tube’s business, with two locations in Sanford, North Carolina, and Oberlin, Ohio, has grown in large part because it is able to supply material under tight lead times.
“Our customer base consists of large OEMs, brands like John Deere, Precor Fitness and Ingersoll Rand, as well as small to medium-size fabricators. Every one of our customers is looking to reduce not only costs, but also lead times in order to cut back the amount of inventory they hold on their floors.”
The BLM LT-FREE High Flex for bent and hydroformed tubes, flat and deep-drawn sheets, or welded assemblies uses twin robots and a dual moving part table handling system, including scrap collection. “We didn’t find any other laser machines that had robotic arms to transition parts,” Althaus recalls.
The new fiber laser has also allowed Hydro Tube to expand the types of metals it can cut; in addition to carbon and stainless, it processes copper, aluminum and other reflective materials that it was not able to manage in the past.
“A robotic arm can come and pick up the tube and present it to the laser head and make rotations,” says Althaus. “Trying to locate or place a fitting in the middle of a 45-degree bend or off the plane or twist is very difficult [without it].’’
Parts do not move during the cutting process. The robotic hand places the part onto the laser where a mounted 5-axis cutting head awaits. There are no part-specific dedicated locating templates necessary to position bent tubes. Using BLM Group programming and simulating software, the reference system makes adapting to the real part directly onto the machine easy.
“The LT-FREE simplifies the process,” according to Althaus. “We’ve had parts in the past that take three fixtures and 60 minutes of setup time over three different milling operations that is now reduced to 5 to 10 minutes of setup time. We can process smaller lot sizes and now have much greater flexibility.”
Once a part is created and recorded in the laser’s system, it’s easy to replicate at any future date. “The time saved is absorbed over the next several runs,” Althaus explains.
Hydro Tube’s cycles fell 60 to 70 percent versus sawing and machining.
Monitoring material
Along with faster cutting times, the BLM keeps track of what parts need miter cutting or trimming at both ends after bending before going into machine operations. “We had a handle bar tube that needed two trimming and two machining operations after bending. It previously took nine minutes. We have cut that down to one 55-second operation on the LT-FREE. When you’re running 6,000 to 7,000 pieces a year, those extra minutes add up quickly,” Althaus says.
Since installing the machine, Althaus says Hydro Tube is looking to increase fabrication of new small or large products. “We will bend products 3 to 4 inches in diameter. As we continue transitioning parts, we’re seeing cycle reductions of 60 to 70 percent versus saw cutting and machining,” he says.
“We also do a 3-inch-diameter roll-bent part where the tube goes through two trim operations followed by machining. It used to take 12 minutes and we’ve got it down to 2 minutes.”
Alternating bays
Potential fiber laser users typically bring BLM a CAD part drawing so that BLM can provide manufacturing simulations that will predict cut times, load times and fixturing, says Andrew Dodd, North American sales director. “The customer has a very accurate understanding of [the laser’s] capabilities before ordering a machine,” he says.
The High Flex model has two separate loading bays so operators can set up in one bay while the other is in use. “Or you can increase production rates by processing in each bay alternately,” explains Dodd. “We can also take the barrier down between the two bays to [create] one large bay for larger parts. This is why Hydro Tube chose the High Flex—it fits their high-mix/low-volume contract manufacturing requirements.” The dual robot configuration provides a high “beam on time” and as a result, higher productivity because the loading and unloading occurs without interrupting cutting.
With labor being harder to come by, says Althaus, the new fiber laser installed at Hydro Tube “reduces the amount of manual labor required to do many of the parts we have.” MM
