Xnexus NXS 150, Operating Manual

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Notice NOT 083
NXS 150
Rev : 00
Date : 13/10/05
SAFETY
4.2. RISK OF INTERNAL INJURIES
GASES AND FUMES
Gases fumes produced during the welding process can be dangerous and hazardous to your health. Arc welding
works have to be carried out in suitable ventilated areas.
Ventilation must be adequate to remove gases and fumes during operation. All fumes produced during welding
have to be removed as soon as they are given off, and as close as possible from the place they are produced to
be the most efficient.
Vapours of chlorinated solvents can form the toxic gas phosgene when exposed to ultraviolet radiation from an
electric arc.
4.3. SAFETY IN THE USE OF GASES (WELDING WITH TIG OR MIG INERT GASES)
4.3.1. COMPRESSED GAS CYLINDERS
Compressed gas cylinders are potentially dangerous. Refer to suppliers for proper handling procedures.
- No impact: secure the cylinders and keep them away from impacts.
- No excess heat (over 50°C)
4.3.2. PRESSURE RELIEF VALVE
Check that the pressure relief screw is slackened off before connecting to the cylinder.
Check that the union is tight before opening the valve of the cylinder. Open it slowly a fraction of a turn.
If there is a leak, NEVER tighten a union, which is under pressure, but first close the valve on the cylinder.
Always check that hoses are in good condition.
4.3.3. DETAILS ABOUT GASES
Gas and gaseous mixtures containing less than 20% of CO
2
:
If these gases or mixtures take the place of the oxygen in the air, there is a danger of asphyxia. An
atmosphere containing less than 17% oxygen is dangerous.
hydrogen and hydrogen-based combustible gaseous mixtures
These are very light gases. In the case of leaks, they collect under the ceiling.
Provide for ventilation at ceiling level.
These are also inflammable gases. The flame of hydrogen is almost invisible. There is therefore a risk of
burns.
Air/hydrogen and oxygen/hydrogen mixtures are explosive in the following proportions:
- 4 to 74.5 % of hydrogen in air.
- 4 to 94 % of hydrogen in oxygen.
Store the bottles in the open or in a well-ventilated place.
Avoid any leakage by limiting the number of connections or couplings to a minimum.
USER’S MANUAL
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