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parts to be coproduced from normally unusable pieces of material—window cutouts, for example—that in a con- ventional stamping operation would be sent for recycling, or stacked and stored for future re-blanking, both of which are wasteful.
Advantages Beyond Throughput Rates
Part makers looking for high vol- umes of simple-shaped parts out the door may not be inclined toward the laser-blanking process. In our example, the stamping line produced the required number of pieces in just 2300 hr., whereas the dual-headed laser needed 3400 hr. to finish the same job.
But, remember that parts/hr. is not the end-all measurement. Costs to maintain dies and tooling dwarf those for laser-blanking consumables. And, tooling and tooling-maintenance costs have skyrocketed as companies that cut AHSS spend about four times what’s required to maintain tooling for mild steel. Comparing this to $40,000/yr. for maintenance on a dual- head laser blanker, concerns over lower throughput can be put to rest.
In addition, laser-cut blanks better lend themselves for secondary opera- tions. With tolerances of ±0.2 mm achievable, tailored blanks that require joining usually can go directly to the welding department. A LaserCoil cus- tomer, for example, prior to laser blank- ing, had to run each of its stamped blanks through a precision shear prior to the laser-welding process. But, laser cutting these blanks provided an edge that could be welded directly to the other part, eliminating secondary shearing and reducing the width of the coil required for processing.
Relatively Simple
For established stampers, an invest- ment in laser blanking may seem dif- ficult to justify and undertake. But, operationally, a coil-blanking system requires no complex foundation or high bays—it can be installed on a flat floor. Laser-blanking units also can be integrated into a direct-feed production
scenario—coupled to a transfer press, for example. This setup further reduces inventory, WIP and production time. They’re also less expensive than com- parably sized mechanical presses, often by 30 percent or more. And, often a system can be retrofitted to an existing coil line with minimal disruption to the production floor.
Given the right software, lasers also can be simple to operate. Custom
coil/strip nesting and CAD/CAM-pro- gramming software (LaserCoil’s Laser- CoilCAM, for example) can help opti- mize part orientation, common-line cutting, nesting and laser parameters. Users import the CAD files, input the coil width, material and thickness, and the software does most of the rest. The software considers grain constraints, multiple cutting heads and peripheral automation. MF
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