800 Agricultural Mechanics and Technology Systems
Copyright Goodheart-Willcox Co., Inc.
to its point of origin, the transducer. The transducer
then serves as a receiver for the refl ected energy. The
returned echoes from the discontinuities and the echo
of the rear surface of the test piece are displayed on the
screen of an oscilloscope, Figure 29-41.
Arc Welding Safety
Welders must always be aware of and take
precautions to avoid the multiple hazards associated
with arc welding. These hazards include the following:
• Electrical shock
• Electromagnetic fi elds (EMF)
• Burns from hot metal
• Burns from intense light
• Burns from steam
• Fire in the surrounding area
• Flying particles
• Fumes and gases
• Explosions from expanding gases
• Tripping on equipment or waste
• Excessive noise
• Moving parts
The preceding list includes most of the hazards
associated with arc welding, but specifi c situations
may create other hazards. The best protection against
hazards is prevention. Many hazards can be avoided
by following safety rules and using good judgment or
common sense.
The Welding Environment
Planning procedures and safely arranging the
work environment should be fi rst considerations in
avoiding hazards. Whenever possible, weld only in
areas that are well-ventilated, dry, and free from clutter.
Flammable materials should be stored well away from
areas where hot metalwork is being performed.
A solid connection of the workpiece lead to the workpiece greatly
reduces the likelihood of electric shock. Electricity always follows the path
of least resistance to ground—make sure that path is not you. Inadequate
ground connections also have the tendency to produce unwanted arcing. This
arcing can cause sparks at the ground connection.
Other people in the vicinity of welding should be protected from the
ultraviolet and infrared rays emitted by the welding arc. Many schools and
businesses use translucent welding curtains for this purpose, Figure 29-42.
shinobi/Shutterstock.com
Figure 29-40. Radiographic testing on a pipeline
that will be buried.
Goodheart-Willcox Publisher
Figure 29-41. In ultrasonic weld testing, discontinuities
are indicated by high or low peaks in the wave
pattern of an oscilloscope.
Previous Page Next Page

Resources and Downloads

Attachments

Extracted Text (may have errors)


800 Agricultural Mechanics and Technology Systems
Copyright Goodheart-Willcox Co., Inc.
to its point of origin, the transducer. The transducer
then serves as a receiver for the refl ected energy. The
returned echoes from the discontinuities and the echo
of the rear surface of the test piece are displayed on the
screen of an oscilloscope, Figure 29-41.
Arc Welding Safety
Welders must always be aware of and take
precautions to avoid the multiple hazards associated
with arc welding. These hazards include the following:
• Electrical shock
• Electromagnetic fi elds (EMF)
• Burns from hot metal
• Burns from intense light
• Burns from steam
• Fire in the surrounding area
• Flying particles
• Fumes and gases
• Explosions from expanding gases
• Tripping on equipment or waste
• Excessive noise
• Moving parts
The preceding list includes most of the hazards
associated with arc welding, but specifi c situations
may create other hazards. The best protection against
hazards is prevention. Many hazards can be avoided
by following safety rules and using good judgment or
common sense.
The Welding Environment
Planning procedures and safely arranging the
work environment should be fi rst considerations in
avoiding hazards. Whenever possible, weld only in
areas that are well-ventilated, dry, and free from clutter.
Flammable materials should be stored well away from
areas where hot metalwork is being performed.
A solid connection of the workpiece lead to the workpiece greatly
reduces the likelihood of electric shock. Electricity always follows the path
of least resistance to ground—make sure that path is not you. Inadequate
ground connections also have the tendency to produce unwanted arcing. This
arcing can cause sparks at the ground connection.
Other people in the vicinity of welding should be protected from the
ultraviolet and infrared rays emitted by the welding arc. Many schools and
businesses use translucent welding curtains for this purpose, Figure 29-42.
shinobi/Shutterstock.com
Figure 29-40. Radiographic testing on a pipeline
that will be buried.
Goodheart-Willcox Publisher
Figure 29-41. In ultrasonic weld testing, discontinuities
are indicated by high or low peaks in the wave
pattern of an oscilloscope.

Help

loading