Praxair Compact 200H 2R Guide De L'utilisateur page 4

b) Do not weld near places containing chlorinated hydrocarbon vapours resultants from degreasing operations.
Reactions can be provoked from the vapours of dissolvents with the resultant heat of electric welding arc
producing toxic or irritating gas.
c) Eye, nose or throat irritations during the welding process means that the ventilation system isn't proper. In this
case the ventilation should be increased in the welding area. Stop the welding operation if the irritations persist.
1.5 Equipment maintenance
The quality of the welding process depends on the good condition of the welding equipment. To maintain it's
goodcondition and protect the operator, maintenance reviews should be made periodically. If reviews aren't
made, accidents can occur due to fire or electric discharges. Therefore:
a) The equipment installation and maintenance operations must be done by qualified personal. Do not
proceed with electric repairs if you are not properly qualified.
b) Before starting with any maintenance operation the welding equipment must be disconnect from the power
supply.
c) The welding cables and the power supply cable and even the welding machine must be kept in good
working conditions. This equipment must never be used in less proper working conditions.
d) The welding equipment and its accessories must be treated carefully. Keep the machine far from heating
sources, ovens or hothouses, from humid places as water wells, oils or lubricants, from corrosive
environments or intemperate weather.
e) Keep the safety systems and the chassis of the machine in proper working conditions.
f) Use the welding equipment only in jobs that are according to the equipment characteristics.
1.6 Using WELDING or GAS CUTTING equipment.
a) The operator of welding or gas cutting equipments must know the specific characteristics and the correct
form of use.
b) The pressures ought to be according to the manufacture recommendations.
c) The welding torches, hoses and reducers must be kept well tightened with no leaks, cleaned and free from
oils or lubricant greases.
d) The pressure reducers can not be submitted to sudden changes of pressure and must be used according to
the manufacturer specifications. Do not use an installation without being equipped with proper retention
valves.
e) Periodical checks must be made to the installation for detection possible gas leaks or other defects.
Qualified personnel must execute the maintenance operations.
1.6 Handling of Gas Tubes
The user must know and follow the safety instructions for stocking, use and transportation of compressed,
liquefied and dissolved gases under pressure used in welding or cutting operations.
Besides the specified norms must follow those that concern the kind of welding process to be used
(Electrode, Tig, Mig, Plasma, Plasmacutting, Laser, etc.), as well as the specific characteristics of the
equipment, the power supply conditions, hygiene norms and safety at work and the machine's safety
regulations . The fulfilment of this safety norms, does not guarantee that the content is enough for all cases
or conditions, or invalids the fulfilment of current legal norms.
2 –MIG/MAG WELDING
Monomig semi-automatic arc welding machines under shield gas use inert gases like argon and mixed argon (MIG
process - Metal Inert Gas) or active gases as CO2 (MAG process - Metal Active Gas).
Carbon steel
Stainless steel
Al Si (aluminium/silicon)
Al Mg (aluminium/magnesium)
CuSi (copper/silicon)
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WELDING METAL SHIELD GAS
100% CO2 (Carbon dioxide)
80% Ár (Argon) + 20% CO2
85% Ar +15% CO2
98% Ar + 2% CO2
95% Ar + 5% CO2
100% Ar
100% Ar
85% Ar + 15% He (Hélio)
200H 2R