Safety considerations, Electric arc welding equipment – MK Products RoboKing User Manual
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CAUTION : READ BEFORE ATTEMPTING INSTALLATION,
OPERATION ORMAINTENANCE OF THIS EQUIPMENT
SAFETY CONSIDERATIONS
ELECTRIC ARC WELDING EQUIPMENT
1-1 INTRODUCTION
This equipment is intended for ultimate appli-
cation by commercial/industrial users and for
operation by persons trained and experienced
in the use and maintenance of welding equip-
ment. Operation should not be undertaken with-
out adequate training in the use of such equip-
ment. Training is available from many public
and private schools or similar facilities.
Safe practices in the installation, operation and
maintenance of this equipment requires proper
training in the art, a careful study of the informa-
tion provided with the equipment, and the use
of common sense. Rules for safe use are gen-
erally provided by suppliers of welding power
sources, compressed gas suppliers, and elec-
trode suppliers. Careful compliance with these
rules will promote safe use of this equipment.
The following Safety Rules cover some of the
more generally found situations. READ THEM
CAREFULLY. In case of any doubt, obtain quali-
fied help before proceeding.
1-2 GENERAL PRECAUTIONS
A. Burn Prevention
ELECTRIC ARC WELDING PRODUCES HIGH
INTENSITY HEAT AND ULTRAVIOLET RADI-
ANT ENERGY WHICH MAY CAUSE SERIOUS
AND PERMANENT EYE DAMAGE AND WHICH
MAY DAMAGE ANY EXPOSED SKIN AREAS.
Wear helmet with safety goggles or glasses with
side shields underneath, appropriate filter lenses
or plates (protected by clear cover glass). This
is a must for welding or cutting (and chipping) to
protect the eyes from radiant energy and flying
metal. Replace cover glass when broken, pitted,
or spattered.
Medical first aid and eye treatment. First aid
facilities and a qualified first aid person should
be available for each shift unless medical facili-
ties are close by for immediate treatment of flash
burns of the eyes and skin burns.
Wear protective clothing - leather (or asbestos)
gauntlet gloves, hat, and high safety-toe shoes.
Button shirt collar and pocket flaps, and wear
cuffless trousers to avoid entry of sparks and
slag.
Avoid oily or greasy clothing. A spark may ignite
them.
Flammable hair preparations should not be used
by persons intending to weld or cut.
Hot metal such as electrode stubs and work
pieces should never be handled without gloves.
Ear plugs should be worn when working on
overhead or in a confined space. A hard hat
should be worn when others work overhead.
B. Toxic Fume Prevention
WARNING: The use of this product may result
in exposure to chemicals known to the State of
California to cause cancer and birth defects or
other reproductive harm.
Adequate ventilation. Severe discomfort, illness
or death can result from fumes, vapors, heat, or
oxygen enrichment or depletion that welding (or
cutting) may produce. Prevent them with adequate
ventilation. NEVER ventilate with oxygen.
Lead-, cadmium-, zinc-, mercury-, beryllium-bearing
and similar materials, when welded or cut, may pro-
duce harmful concentrations of toxic fumes. Ade-
quate local exhaust ventilation must be used, or
each person in the area, as well as the operator,
must wear an air-supplied respirator. For beryllium,
both must be used.
Metals coated with or containing materials that emit
toxic fumes should not be heated unless coating
is removed form the work surface, the area is well
ventilated, or the operator wears an air-supplied
respirator.
Work in a confined space only while it is being
ventilated and, if necessary, while wearing an air-
supplied respirator.
Gas leaks in a confined space should be avoided.
Leaked gas in large quantities can change oxygen
concentration dangerously. Do not bring gas cylin-
ders into a confined space.
Leaving confined space, shut OFF gas supply at
source to prevent possible accumulation of gases in
the space if downstream valves have been acciden-
tally opened or left open. Check to be sure that the
space is safe before reentering it.
Vapors from chlorinated solvents can be decom-
posed by the heat of the arc (or flame) to form
PHOSGENE, a highly toxic gas, and other lung
and eye irritating products. The ultraviolet (radiant)
energy of the arc can also decompose trichloroeth-
ylene and perchloroethylene vapors to form phos-
gene. DO NOT WELD or cut where solvent vapors
can be drawn into the welding or cutting atmo-
sphere or where the radiant energy can penetrate
to atmospheres containing even minute amounts of
trichloroethylene or perchloroethylene.
C. Fire and Explosion Prevention
Causes of fire and explosion are: combustibles
reached by the arc, flame, flying sparks, hot slag, or
heated material, misuse of compressed gases and
cylinders, and short circuits.
BE AWARE THAT flying sparks or falling slag can
pass through cracks, along pipes, through windows
or doors, and through wall or floor openings, out
of sight of the goggled operator. Sparks can fly
many feet.
To prevent fires and explosion:
Keep equipment clean and operable, free of oil,
grease, and (in electrical parts) of metallic particles
that can cause short circuits.
If combustibles are in area, do NOT weld or cut.
Move the work if practicable, to an area free of
combustibles. Avoid paint spray rooms, dip tanks,
storage areas, ventilators. If the work cannot be
moved, move combustibles at least 35 feet away,
out of reach of sparks and heat; or protect
against ignition with suitable and snug-fitting,
fire-resistant covers or shields.
Walls touching combustibles on opposite sides
should not be welded on (or cut). Walls, ceil-
ings, and floor near work should be protected by
heat-resistant covers or shields.
Fire watcher must be standing by with suitable
fire extinguishing equipment during and for
some time after welding or cutting if:
1. Appreciable combustibles (including building
construction) are within 35 feet.
2. Appreciable combustibles are further than 35
feet, but can be ignited by sparks.
3. Openings (concealed or visible) in floors or
walls within 35 feet may expose combustibles
to sparks.
4. Combustibles adjacent to walls, ceilings,
roofs, or metal partitions can be ignited by radi-
ant or conducted heat.
Hot work permit should be obtained before
operation to ensure supervisor’s approval that
adequate precautions have been taken.
After work is done, check that area is free of
sparks, glowing embers, and flames.
An empty container that held combustibles, or
that can produce flammable or toxic vapors
when heated, must never be welded on or
cut, unless container has first been cleaned in
accordance with industry standards.
This includes: a thorough steam or caustic
cleaning (or a solvent of water washing,
depending on the combustible’s solubility), fol-
lowed by purging and inerting with nitrogen or
carbon dioxide, and using protective equipment.
Water-filling just below working level may sub-
stitute for inerting.
A container with unknown contents should be
cleaned (see paragraph above). Do NOT
depend on sense of smell or sight to determine
if it is safe to weld or cut.
Hollow castings or containers must be vented
before welding or cutting. They can explode.
Explosive atmospheres. NEVER weld or cut
where the air may contain flammable dust, gas,
or liquid vapors (such as gasoline).
D. Compressed Gas Equipment
The safe handling of compressed gas equip-
ment is detailed in numerous industry publica-
tions. The following general rules cover many
of the most common situations.
1. Pressure Regulators
Regulator relief valve is designed to protect
only the regulator from overpressure; it is not
intended to protect any downstream equipment.
Provide such protection with one or more relief
devices.
Never connect a regulator to a cylinder contain-
ing gas other than that for which the regulator