Cutting Quality Goes Bad After Some Time

[instind]

Hi,

We are cutting 2.7mm mild steel using a 1.5kw fiber laser cutting machine. We have nested the part on a sheet and cutting is going on continuously. After about an hour of cutting, the edge quality starts degrading progressively. We have not changed any parameters. The O2 gas is also from the same source and there is sufficient quantity of gas at the required pressure. What could the possible causes be?

Thanks!

 

[LaserEngine]

Have you checked the nozzle so it isnt clogged or deformed?

 

[JayMaechtlen]

If quality changes, then either the beam quality is changing, the delivery (lens/nozzle performance/nozzle standoff) is changing, or the gas (pressure or quality) is changing.
I haven't worked with a fiber laser - I presume there's a focus lens and perhaps some optics between the fiber and the lens? Any of those could heat up due to cooling issues - when optics heat up they often change characteristics, perhaps changing the effective location of the beam spot.


Jay Maechtlen

http://www.laserpubs.com/techcomm

 

[instind]

I have checked the nozzle and it isn't clogged. I have now reduced the chiller temperature setting and will see if that improves the cut quality. Thanks!

 

[krugtech]

does it recover and start cutting good again?


Chris Krug

http://krugtech.com/

Maximum Up-time, Minimum BS