3D lasers cut a wider product swath: rethinking the way parts are processed.

There's more than one way to produce components from sheetmetal and structural pipe and tube. Typically, machining and fabricating shops have relied on traditional processing techniques, machining centers and turning centers, for processing structural parts and 2D lasers, turret punch presses, and press brakes to cut, punch, and bend sheetmetal parts for welding.

Lasers, which vaporize and melt workpiece materials such as Inconel, titanium, and tool steel, are becoming a very real competitive option to traditional parts processing methods. Since laser processing doesn't involve contact with the workpiece, sophisticated fixturing is not required and parts can be redesigned for easy assembly. Generally, the maximum thickness of a workpiece is determined by the laser oscillator output. For example, a 4 kW C[O.sub.2] laser can cut 15 mm (0.59") stainless steel, 20 nun (0.79") tool steel, and 25 mm (0.98") mild steel. Thickness is reduced for 3D lasers.

Dramatic improvement in multi-axis laser machines and the software to optimize machine utilization and generate NC code from 3D CAD drawings, created offline or online, have expanded the range of parts produced on lasers. 3D rotary laser machines can be programmed to cut complex 3-dimensional parts, as well as automatically design and generate NC code for workholding fixtures, complete with tabs and slots, for fastening without fixtures, says Mazak Nissho Iwai, Schaumburg, IL.

The result is that 3D rotary lasers are shortening design and fabricating times, consolidating multiple operations, and simplifying the fabrication of parts that were previously machined with multiple tools and setups. The laser's processing flexibility is leading some users to change parts design.

For example, laser-processed tube designed with tabs and slots allow the tractor and trailer chassis (shown) to be cut from pipe and fabricated without expensive welding fixtures and their associated costs. Components were bent and assembled using tabs and slots that were designed into the components.

When applied to sheetmetal processing, 3D laser processing replaces conventional fabricating steps that include 2D sheetmetal cutting, bending, assembly, and welding. Using materials like pipe and tubing, 3D laser cutting produces monolithic parts that are structurally more rigid, free of thermal distortion, and without the need for skilled press brake operators or welders.

At Fabtech 2003, Mazak showcased its 3D rotary laser processing capabilities in its 3D Laser Factory or "idea center" of applications, which demonstrated the design engineering and production possibilities with its 3D laser equipment and Space Cam software.

Production Cutting Services Inc., East Moline, IL, is using a SG-U44 3D rotary laser to process a tubular farm equipment component from 4" x 4" rectangular 0.25" tube. The part has holes on all four sides and the position of the holes in relation to each other must be held within [+ or -] 0.010".

The part was very complicated to process manually. First it had to be cut to length, fixtured on one of two vises (each vise held the part for two positions). The operator had to turn the tube manually for the next side. Once holes were drilled, the operator had to hand deburr the inside edges of the holes. Besides being time-consuming and labor intensive, the potential for operator error was very high and chip contamination could throw part positioning off.

Using the SG-U44 3D rotary laser, Production Cutting has reduced three operations to one, reduced cycle time by 40 percent, and is making ten parts per cycle instead of one. A 10-ft tube is positioned in the rotary chuck. The laser is programmed to cut the right holes in the right face and the rotary chuck automatically rotates the part, eliminating manual turning. And, of course, there is no debris to affect part positioning in a vise or need to grind burrs. After holes are cut, the laser cuts the part off at the correct length and starts the next part. Not only is the process reduced to one operation and one setup, but the company is getting ten parts per chucking.

For CVC, a job shop in Florence, KY, installing Mazak's 3D rotary Space Gear laser machine led to one setup production of an inner column support made from 6" x 6" square steel tubing with a 7 gage wall. The part is 15" long with 32 holes of three different sizes on all four sides. The part happens to be the shape of available tubing, which CVC buys cut to a slightly-oversized length. The cut tube is mounted on the chuck of the Space Gear with the straight edge against the chuck. By the time the part rotates three times, the part is completed with 32 holes and notched end cuts--all in one operation.

The time it takes to make one part on the Space Gear is about one quarter to one third the previous processing time. Previously it required six operations to make the part. The materials first had to be sheared, holes punched on a turret punch press, deburred, and notched out the edge. Another sheared blank was processed and then the two blanks were formed into an angle and the legs welded together to make the square tube shape.

Laser line up

Mazak's line up of C[O.sub.2] laser processing machines includes the newly-introduced FabriGear 150 tube laser that automatically loads, feeds, laser cuts, and unloads tube, pipe, and structural materials up to 5.9" diameter. Like the FG-300, which processes tube in diameters up to 11.8", the FG150 is designed for 2D and 3D-rotary processing in job shops and production houses. The FG-150 fabricates round, square, rectangular, and triangular pipe as well as I and H beams, C channel and angle iron with no stopping for setups or other manual changes. FG software features fill-in-the-blank screens to quickly generate NC code. A 64-bit NC and simultaneously-controlled 3D cutting head allow the 3D-rotary system to perform coping in one operation. It also cuts precise angles, weld-prep bevels, and complex contours.

Other laser processing machines include:

* The SG-U44 multi-axis rotary C[O.sub.2] laser is designed as a compact production laser that performs high-speed 2D processing of sheetmetal and plate, as well as 3D cutting of pre-formed parts, pipe, and structural steel. In rotary mode, the SG-U44 performs 2D and 3D cutting of tube, including rectangular and triangular pipe as well as C, H, I, and L beams. The 5-axis torch and simultaneously-controlled chuck allow the SG-U44 to fabricate angle cuts, weld-prep bevels, and advanced contours such as saddle joint cuts in one operation.

With its multi-axis torch, the SG-U44 laser-cuts stamped, hydroformed, and spun pre-formed parts as well as high-speed 2D cats and bevels in flat material. An automatic feeder option enables continuous processing of mill-length pipe. Mazak's SpaceCam software option generates NC code from a 3D CAD drawing, imported or crafted in the system. It can also generate code for a slot-and-tab workholding fixture. The SG-U44 can process any length pipe and up to 4 ft x 4 ft x 1" sheet.

* Space Gear 48 is a triple-mode C[O.sub.2] laser cutting machine for 2D high-speed production cutting of sheetmetal and plate up to 1" thick, as well as 3D cutting of preformed parts, plus 2D and 3D cutting of pipe and structural steel. In 3D mode, the Space Gear can bevel-cut flat material and cut pre-formed parts, which are stamped, hydroformed, or spun. It can cut complex contours with weld-prep bevels, plus cut any size or shape hole, all in one operation. The machine processes pipe and rectangular and triangular tube as well as C, H, I, and L beams. The Space Cam software option allows generation of NC cutting code from a 3D CAD drawing, and it can automatically design and generate NC code for a workholding fixture. It is available with a 4 ft x 8 ft or 5 ft x 10 ft table.

* Mark II high-speed C[O.sub.2] laser machine for processing sheetmetal features its high-speed pierce, which accelerates processing of hole-intense parts, while changing from one material or thickness to another is automatic. There are no time-consuming torch changes or manual adjustments needed, reducing idle time, the most significant factor in reduced processing times.

Mazak Nissho Iwai, www.rsleads.com/402tp-175