Miller Electric CBI 801D - Manual (Page 9)

OM-166 941 Page 4
1-3. ARC WELDING
Comply with precautions in 1-1, 1-2, and this section.
Arc Welding, properly done, is a safe process, but a
careless operator invites trouble. The equipment carries
high currents at significant voltages. The arc is very
bright and hot. Sparks fly, fumes rise, ultraviolet and in-
frared energy radiates, weldments are hot, and com-
pressed gases may be used. The wise operator avoids
unnecessary risks and protects himself and others from
accidents. Precautions are described here and in stan-
dards referenced in index.
A. Burn Protection
Comply with precautions in 1-2.
The welding arc is intense and visibly bright. Its radiation
can damage eyes, penetrate lightweight clothing, reflect
from light-colored surfaces, and burn the skin and eyes.
Skin burns resemble acute sunburn, those from gas-
shielded arcs are more severe and painful. DON’T GET
BURNED; COMPLY WITH PRECAUTIONS.
1. Protective Clothing
Wear long-sleeve clothing (particularly for gas-shielded
arc) in addition to gloves, hat, and shoes (1-2A). As nec-
essary, use additional protective clothing such as
leather jacket or sleeves, flame-proof apron, and fire-re-
sistant leggings. Avoid outer garments of untreated cot-
ton.
Bare skin protection. Wear dark, substantial clothing.
Button collar to protect chest and neck and button pock-
ets to prevent entry of sparks.
2. Eye and Head Protection
Protect eyes from exposure to arc. NEVER look at an
electric arc without protection.
Welding helmet or shield containing a filter plate shade
no. 12 or denser must be used when welding. Place over
face before striking arc.
Protect filter plate with a clear cover plate.
Cracked or broken helmet or shield should NOT be
worn; radiation can pass through to cause burns.
Cracked, broken, or loose filter plates must be replaced
IMMEDIATELY. Replace clear cover plate when broken,
pitted, or spattered.
Flash goggles with side shields MUST be worn under
the helmet to give some protection to the eyes should
the helmet not be lowered over the face before an arc is
struck. Looking at an arc momentarily with unprotected
eyes (particularly a high intensity gas-shielded arc) can
cause a retinal burn that may leave a permanent dark
area in the field of vision.
3. Protection of Nearby Personnel
Enclosed welding area. For production welding, a sepa-
rate room or enclosed bay is best. In open areas, sur-
round the operation with low-reflective, non-combusti-
ble screens or panels. Allow for free air circulation, par-
ticularly at floor level.
Viewing the weld. Provide face shields for all persons
who will be looking directly at the weld.
Others working in area. See that all persons are wearing
flash goggles.
Before starting to weld, make sure that screen flaps or
bay doors are closed.
B. Toxic Fume Prevention
Comply with precautions in 1-2B.
Generator engine exhaust must be vented to the out-
side air. Carbon monoxide can kill.
C. Fire and Explosion Prevention
Comply with precautions in 1-2C.
Equipment’s rated capacity. Do not overload arc weld-
ing equipment. It may overheat cables and cause a fire.
Loose cable connections may overheat or flash and
cause a fire.
Never strike an arc on a cylinder or other pressure ves-
sel. It creates a brittle area that can cause a violent rup-
ture or lead to such a rupture under rough handling.
D. Compressed Gas Equipment
Comply with precautions in 1-2D.
E. Shock Prevention
Exposed hot conductors or other bare metal in the weld-
ing circuit, or in ungrounded, electrically-HOT equip-
ment can fatally shock a person whose body becomes a
conductor. DO NOT STAND, SIT, LIE, LEAN ON, OR
TOUCH a wet surface when welding, without suitable
protection.
To protect against shock:
Wear dry insulating gloves and body protection. Keep
body and clothing dry. Never work in damp area without
adequate insulation against electrical shock. Stay on a
dry duckboard, or rubber mat when dampness or sweat
can not be avoided. Sweat, sea water, or moisture be-
tween body and an electrically HOT part or grounded
metal reduces the electrical resistance, and could en-
able dangerous and possibly lethal currents to flow
through the body.
A voltage will exist between the electrode and any con-
ducting object in the work circuit. Examples of conduct-
ing objects include, but are not limited to, buildings, elec-
trical tools, work benches, welding power source cases,
workpieces, etc. Never touch the electrode and any
metal object unless the welding power source is
off.
1. Grounding the Equipment
Arc welding equipment must be grounded according to
the National Electrical Code, and the work must be
grounded according to ANSI Z49.1 “Safety In Welding
And Cutting.”
When installing, connect the frames of each unit such as
welding power source, control, work table, and water cir-
culator to the building ground. Conductors must be ade-