Jeff Arendas, lasertube product manager with the BLM Group, says there is a trend towards larger capacity machines that can cut bigger diameter pipe. On a historical perspective, most tube cutting lasers sold in North America can cut up to a 6-in.-diameter. But customers have been demanding that tube-laser manufacturers increase the sizes of pipes or tubes the equipment can process.
“Customers that work with larger tubes are looking for a more accurate way to cut them,” says Arendas. “Traditionally a lot of this larger, heavier tubing has been done using plasma systems or even machining centers. With laser-tube cutting you can incorporate multiple manual operations into a single automated process.
“Plus the laser will give you far greater precision along with better edge quality and cleaner, straighter, squarer holes.”
Therefore, the number one trend in laser tube cutting is larger, and the other innovation is the advent of the fiber laser resonator as a replacement for traditional C02 he mentions.
At Fabtech 2010 the BLM Group showed a fiber laser that is being used on the company’s 6-in. diameter family of machines. The fiber-laser technology adds new capabilities to laser tube cutting while at the same time dramatically reduces the operating cost per hour and eliminates the maintenance requirements associated with CO2 lasers.
A fiber laser does a superior job in aluminum, copper, brass and galvanized materials he remarks. All of these are difficult or impossible to cut with a CO2 laser.
“When we cut galvanized steel, it makes a plume above the cut. A CO2 beam tends to disperse in this zinc cloud and also gets absorbed in it. But the shorter wavelength of the fiber laser penetrates right through the zinc plume, and all the energy gets delivered to the material. As a result it just cuts the galvanized materials wonderfully,” he says.
Fiber lasers are known for doing an excellent job in thinner materials from 0.25 in. and below. In this area, the fiber beats the CO2 laser says Arendas. When the thickness approaches 0.375 in., the CO2 laser does a better job.
For their 6-in.-diameter cutting-range lasers, BLM Group still offers both types of laser resonators. “It’s basically the same machine, the only difference is the resonator and a different enclosure scheme,” he adds.
Mazak Tube and Pipe Lasers
With 42 different models of tube and pipe cutting lasers, Mazak offers various combinations of lasers that can process a wide diversity of different applications.
“We have one machine called an RTC (rotary, tapping, chamfering), that not only does flat cutting of sheets, but it also has a rotary attachment for cutting tubing,” says Keith Leuthold, director of inside sales.
“We also have some machines that are dedicated just to cutting tubing or structural components such as angles, channels, I-beams and any type of open or closed geometry. These parts can be up to 26 ft. long, although we do offer longer versions. This machine is called a FabriGear, and it’s dedicated to cutting just long tubes or structural components.”
A laser that can cut both flat and round stock allows a job shop to have greater versatility says Leuthold. However, he mentions, “If a job shop wasn’t cutting thousands of tubes, they probably would go to a multi-axes, multi-function laser that could do a wide variety of different cuts. Certainly one of these machines would be better justified and less expensive, but is more versatile and flexible for doing a wide range of different jobs, including formed 3-D parts,as well as flat parts.”
Mazak’s FabriGear can cut structural I-beams and H-beams. To cut these various types of parts, they use different jaw attachments to rotate the tube depending on the cross-section shape of the raw material. The FabriGear has a multi-axis, articulating, robotic-type cutting head with six axes of motion. It has a head with an A and B axis to get into very tight areas and circle around a tube, channel or I-beam.
For applications other than tubing such as angles, channels and I-beams, what are called open geometries, then Mazak offers its V-Series FabriGear that can process a wider range of different parts along with heavier parts. Mazak’s FabriGear 150 laser can handle parts up to 30 pounds per ft. and the FabriGear 300 can handle a part up to 40 pounds per ft. These machine structures are designed for heavier parts. For applications involving 100’s of the same, closed-shaped tubes, a bundle-feeder version is offered.
Mazak’s Space Gear Laser Systems offer a 2-D mode for flat sheet and plate up to 0.87 in. thick. Its 3-D mode makes use of a compact cutting head with ±360 degrees of rotation in the A axis and ±135 degrees in the B axis to maintain a normal cutting angle to all preformed sculptured surfaces for tubes, pipes or other structures. Being able to tilt the head allows for tighter fit ups and fixtureless welding. A non-contact profiler maintains a constant stand-off distance and eliminates part marring.
Flexibility for a job shop is often paramount. It allows the company to do more with their existing equipment while not having to purchase more equipment to do different processes. With this concept, PrimaPower offers a rotary axis on all of their laser systems to cut tube, pipe and structural components. With the company’s five-axis laser, it offers the user even more flexibility to cut features.
“As part of all of our 2-D machines and our 3-D crossover machines, we offer an optional rotary axis on each one of them,” says Mike Millette, PrimaPower’s laser product manager.
“For job shops that aren’t doing full production runs of thousands of tubes, but are processing shorter production of 1000 pieces or less, they work very well. We can do both 2-D and 3-D cutting on tubes as well, depending if the customer has a 2-D or 3-D machine. They can cut out oblong, square, round and rectangular tubes. There’s really no feature or shape that can’t be cut.”
Tube-wall thickness that the machine can cut ranges from 0.125 in. to 0.375 in., and this can be either mild steel or stainless. Because of the forces the chuck can place on the tube, thin-wall tubes could be in danger of being crushed mentions Millette.
Tube diameters that the lasers can process range from an 1.5 in. up to 11.5 in. The chuck has the capability of passing through a tube up to 6 in. in diameter or 4-in.-square tubing.
Also the lasers can use a bar feeder to feed tube in automatically. The laser can stop the tube, cut it and then continue feeding tubes Millette says. The rotary system comes with two completely adjustable steady rests in the X and Y axis. Chuck jaws adjust for the diameter of the tube.
“If a company has a Prima laser, a tube-cutting system can be retrofitted to it. Our machines come predispositioned so a customer can add this option at any time. All the software and wiring are already in the machine. This feature allows a customer who has a Prima machine to branch out to serve other customers when tube cutting is in demand. Plus it gives a job shop a more precise cut over a plasma system,” remarks Millette.
Although TRUMPF has offered a tube-cutting laser for many years, they’ve added features to the system to make it even more flexible.
The company has now introduced its third iteration of tube processing, the RotoLas III option that allows their 2-D lasers to process tube, pipe and other structural components, offering greater versatility.
“RotoLas avails the customer of new opportunities in fabricating, including greater business potential. It also allows them to keep more business in-house,” says Dave Gilmore, applications engineer. “One of the new features is that we opened up the pass-through area, allowing a larger tube to be inserted more quickly from outside of the machine and continuously fed. This feature can now handle many types of tube profiles that can fit into a 6.5-in. diagonal. Also, tube support is now fully programmable, able to move to new positions at any time during the program.
Gilmore also mentions that the chuck now uses a digital-drive system that allows for faster and more precise cutting. Rather than using a pivoting chuck to access full tube ranges, it now uses a single-position chuck that is “much more user friendly,” he says.
TRUMPF’s RotoLas III is featured on the TruLaser 3030 NEW. It can cut up to a 0.5-in. wall thickness with a tube that weighs up to 440 lbs. The RotoLas III also uses specialized cutting data specific for tube.
In addition, it uses an ergonomic, user-friendly touch-screen with dialogue-driven menus. The operator is prompted throughout the tube-cutting procedure and confirms any move before the cutting head makes it.
TRUMPF’s TruLaser Tube 7000 is a dedicated multi-axis laser-cutting machine for tube and structurals. The machine’s primary focus is designed for full, automated tube and pipe processing. It uses a new ergonomic, user-friendly, touchscreen control panel that is menu-driven. Along with running full production, a new feature allows for a quick interruption during the processing for individual tube cutting, even though the profiles may not be the same. The operator can then quickly return to the original, fully automated production cycle. It can be manually loaded for processing on short sticks, or set for full, lights-out production from a bundle of tube, notes Gilmore.
It can cut up to 0.375-in.-wall thickness with tube sizes ranging from 0.625 in. to 8 in. weighing up to 320 lbs. With an optional 10-in. chuck, it can process 10-in.-diameter tubes weighing up to 550 lbs.
Mazak Optonics Corp.
BLM photos on ftp site for magazine