
B-70264EN/02 1.NOTES ON USE
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1.3 LASER GAS
1.3.1 Laser gas specification
Supply the laser oscillator with a mixture of gases that satisfy the
conditions listed below.
(1) Composition ratio and accuracy
(For the composition ratio, check the label and specifications of
the oscillator.)
Gas A Gas B Gas C
CO
2
5±0.25% 5±0.25% 5±0.25%
He 40±2% 60±3% 70±3.5%
N
2
55±2.75%
(N
2
balance)
35±1.75%
(N
2
balance)
25±1.25%
(N
2
balance)
(2) Water (H
2
O): 5 ppm or less
(3) Hydrocarbon (C
n
H
m
): 1 ppm or less
(4) Gas purity: 99.99% or higher
1.3.2 Supply Gas Pressure
Set the pressure so that the secondary pressure as measured at the
regulator on the laser gas cylinder falls into the range of
0.175MPa±0.025MPa.
1.3.3 Replacing the Laser Gas Cylinder
If the primary pressure of the regulator installed in the laser gas
cylinder is 1 MPa or less, replace the laser gas cylinder with new one.
When laser gas runs out during oscillator operation, the oscillator
stops automatically. In this case, after the oscillator stops, replace the
gas cylinder.
When replacing the gas cylinder, close the main plug of the gas
cylinder, completely loosen the adjustment valve of the regulator,
then remove the regulator. If the adjustment valve of the regulator is
left tightened, external air will enter the piping. When the oscillator is
started after the replacement of the cylinder, the external piping
exhaust operates to remove gas inside the piping, and the oscillator
starts in the normal sequence.
When laser gas runs out during purging, a stop occurs while the inside
of the piping is in the negative pressure state. If the gas cylinder is
replaced in this state, the atmosphere is sucked. Therefore, be sure to
loosen the adjustment valve of the regulator before removing the
regulator.
Before the oscillator starts, the external piping exhaust operation
takes place then the automatic aging function operates to perform
aging in the oscillator to prevent possible troubles from occurring if
the atmosphere should be sucked.