B FIGURE 1 Laser blanking uses a flexible
stacker, capable of handling multiple parts
at a time.
By Charles Caristan and Jay Finn
A A Cover Story
When you think of high- volume blanking, a coil processing line, a mechanical press, and
blank-stacking equipment probably
come to mind. A typical mechanical
press may cost $1.5 million to $2.5
million for a bed size 11. 5 to 15 feet
long and the tonnage required to run
parts at 12 to 25 strokes per minute
(SPM). With this comes a massive pit
for the mechanical blanking press, as
well as a higher ceiling so the huge machine can be installed and maintained.
Bolsters for quick die change require
significant operational floor space, and
even more floor space is needed to
store various die sets that blank different parts running through the press.
Meanwhile the auto industry, that
bastion of high-volume production, has
changed. The industry now demands
lower volumes and just-in-time production with minimal inventory to
handle ever-more-frequent design
changes. For blanking, this has made
hard tooling a greater liability. Quick
die change has helped presses change
over quickly, making shorter runs more
efficient. But it still doesn’t change the
fact that hard tools need to be changed
out in the first place.
But what if there were no hard tools?
For many years CO2 laser cutting
systems have dominated blanking for
low-volume and prototype requirements. But until recently the laser simply wasn’t cost-effective for high-volume blanking. Now, however, high-powered fiber lasers provide a long-overdue, viable alternative to the
blanking press (see Figures 1 and 2).
Fiber Laser Advantages
High-powered fiber lasers have become
a cost-effective alternative to the blanking press
Ten years ago a 6-k W CO2 laser with
10 percent wall plug energy efficiency
could cut 0.040-inch-thick steel at 98
feet per minute. Today a 5-k W multimode fiber laser requires about 20 kVA
of electrical power and has a wall plug
energy efficiency of about 25 percent—
more than double that of a 6-k W CO2
laser. It can cut material 0.040 in. thick
at 197 FPM. Such fiber lasers have
beams with wavelengths in the 1-mi-
cron range, delivered through fiber optics. Fiber delivery eliminates periodic
downtimes for mirror alignment and
cleaning and variations in cut quality
and speed.
The FABRICATOR® | An FMA Publication
www.thefabricator.com | November 2009
