By Brett Thompson
Since the Industrial Revolution, manufacturing
processes have become safer, more efficient, and
more profitable because of advancements in manufacturing technologies. No single technology has
been more impactful to the world of sheet metal
manufacturing than the laser. Its influence can be
witnessed across the entire spectrum of manufacturing processes when it’s used not only as a tool for
cutting, but also for welding.
Laser welding is almost paradoxical in how flexible it is in regard to weld joint geometries. When
you consider how restrictive the requirements are
for maximum permissible gap, it’s easy to see why.
While it’s true that you should maintain a minimal
gap seam, the broad range of ways to assemble
a part for laser welding means that you can easily
overcome those restrictions. It’s a reality that is not
only surprising, but hugely beneficial when considering its effects on upstream processes.
While North American manufacturers are showing
greater interest in using laser welding as a tool to re-
duce production costs, most think of laser welding’s
benefits along more traditional lines: reducing or
outright eliminating rework. If you have a cosmetic
component—let’s say a stainless steel appliance for
a residential kitchen—you can spend a lot of money
on non-value-added processes such as grinding,
polishing, and straightening in an attempt to correct
the aesthetic imperfections inherent in the conven-
tional welding process. All of this is true, but the
benefits of laser welding can reach farther, going all
the way back to the thickness of the materials that
BUILDING A STAINLESS STEEL TANK
There are two different ways to construct a sealed
stainless steel tank. Let’s say you use 3-mm stainless
steel for the body and a tube of the same thickness
and material that passes entirely through lengthwise.
The component isn’t pressurized so you can select
a thinner material to reduce manufacturing costs.
However, you need thicker side walls for the inserted
tube because of the greater strength requirements
on the ends.
A modern laser can cut this part quickly, consistently, and with good edge quality (see Figure
1). A modern press brake will give us a good initial
outcome, allowing us to change from job to job in
minutes. Today we can make this part efficiently and
reliably; nevertheless, this part can be improved.
THE CASE FOR
Analyzing laser’s effect on a sample part