By: Editorial team
Reading time: 3 Minutes
◤ METAL PROCESSING
Raising process reliability in laser cutting
The trend toward higher laser outputs in laser cutting affects the entire process. It is becoming more efficient overall, but focusing even more energy is also making it more sensitive to particle loading. The higher energy density can potentially cause the particles to be burned onto the surface of the cutting optics. Messer offers several different solutions designed to protect the equipment and maintain its efficiency.
Laser cutting has made great strides in recent years. Modern fiber lasers can achieve 40 percent efficiency, or about four times that of conventional CO₂ lasers. With higher efficiency, beam power also increases: Where 8 kilowatts once represented the upper limit in laser cutting, more powerful machines now reach up to 30 kilowatts. That also makes sense when cutting plain and low-alloy steels with nitrogen.
Any material that the laser beam melts or vaporizes is blown out of the kerf by the cutting gas. With modern high-power machines, the trend here is toward nitrogen, an inert cutting gas that protects the cut surfaces against oxidation.
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At Messer, we don’t just supply gases to our customers. Rather, we share the responsibility for the optimal performance of their application.
Dr. Bernd Hildebrandt, Cutting Applications Expert at Messer
Particle loading from gas lines
“We supply our cutting gases with a high, precisely defined purity. Between the vaporizer and the transfer to the customer’s piping network, we include a filter system. This eliminates the possibility of any appreciable particle loading,” emphasizes Dr. Bernd Hildebrandt, cutting applications expert at Messer. “But impurities can find their way into the gas further downstream on its way to the cutting machine. The quality of the piping installation has a huge influence on the number and size of particles in the cutting gas.” High-quality materials and the surface finish of the pipes along with careful processing are of fundamental importance here. One not uncommon cardinal error, for example, is when copper pipes are not formed when soldering. Oxides then form, which later detach from the pipe and enter the cutting gas stream as particles.
Contents of a filter cartridge after about one year in operation. The cartridge element reliably filtered out solid particles that otherwise could have been burned into the cutting optics and clouded/damaged the optical system as a result.
Filter for machine or line
In such cases, a particle filter installed as close as possible to the cutting head can provide effective protection, removing harmful impurities from the gas. Messer collaborates with proven suppliers to find optimal solutions. Our partners – Messer Cutting Systems, for example, and other laser cutting machine manufacturers – take care of optimizing the integration of filter units within the machines. This of course also includes making it easy to replace the filter as well.
“At Messer, we don’t just supply gases to our customers. Rather, we share the responsibility for the optimal performance of their application. For the relatively new problem of particulate impurities, we offer pragmatic solutions. Customers benefit from our gases expertise and the individual support,” sums up Dr. Bernd Hildebrandt.