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BM115 SERIES 6-12KW Laser Cutting Head User Manual
2.2.2
Assist gas interface
The impurity in assist gas such as hydrocarbon and steam will damage the lens and cause cutting
power fluctuation as well as inconsistencies between the sections of the work piece. The table
below is the recommended auxiliary gas specification. The higher the purity of the gas, the better
the quality of the cutting section.
Impurity can be filtered out in gas supply tube, but Oxygen and water vapor can permeate light
path through nonmetal materials, which is the source of the appearance of dust and
hydrocarbon. Stainless steel fittings are recommended, at the same time must use filters which
can remove a minimum of 0.01 micron particle to purify.
A pressure gauge with a stainless steel diaphragm is recommended. Industrial pressure gauges
suck in air. Rubber diaphragm produce hydrocarbon by aging or other factors.
N2 or fine filtered air with pressure less than 1 bar is recommended for nozzle cooling. The O2
is prohibited for nozzle cooling.
Outer diameter of water pipe caliber
6mm
Minimum flow speed
1.8 l/min(0.48 gpm)
Entry pressure
170-520kPa (30-60 psi)
Entry temperature
≥room temperature /
＞
dew point
Hardness (relative to CaCO3)
＜
250mg/liter
PH range
6 to 8
Particle size allowed
Diameter less than 200 microns
Gas
Purity
Maximum content of water vapor Maximum content of hydrocarbon
oxygen
99.95%
<5 ppm
<1 ppm
nitrogen
99.99%
<5 ppm
<1 ppm
argon
99.998%
<5 ppm
<1 ppm
helium
99.998%
<5 ppm
<1 ppm
Diameter of auxiliary gas
pipe (Outer diameter)
10mm
Diameter of cooled gas
pipe (Outer diameter)
8mm
