418 Flashcards
(25 cards)
In oxyfuel welding, you can control the rate of heat input to the base metal by varying the
Speed of the torch
In torch brazing, the filler metal is distributed in the joint as a result
Capillary action
The purpose of using a flux in welding and brazing is to
Clean the base metal
The purpose of post heating is to
Reduce stresses in welding structures
When you weld low carbon steel you should
Dip the filler rod in to the weld puddle
When welding aluminum, you need to remember that aluminum
Conducts heat away rapidly from the weld site
In preparing aluminum parts for welding, you should ___ the surfaces to be welded
Scrape or file
When welding brass, you should use
Flux
What kind of flame should be used when welding lead? ___ nickel? ____ Magnesium? ___
Neutral, Carburizing, Carburizing
To make the best possible welds using oxyfuel equipment you should know
Know what metals your joining
Oxyfuel welding and oxygen cutting are alike in that both processes
Requires lighting the torch with a spark lighter
Which of the following must be worn during an oxygen cutting operation?
Goggles with dark lenses
When piercing a steel plate with an oxygen cutting torch, which step should be performed first?
Heat the spot to a bright red
The purpose of scaring is to
Remove a surface defect from unfinished steel
If you need to cut a metal other than mild steel or medium carbon steel you might make a difficult job easier if you lay
Lay a bead of low carbon steel along the cut line
The oxyfuel process in which the base metal is not melted and the filler metal is drawn into a thin joint by capillary action is called
Brazing
the purpose of using flux in brazing is to
eliminate oxides from the metal surfaces
A special concern when brazing is that the filler metal melts at a temperature really near the melting point of the base metal
Aluminum
when brazing and braze welding which of the following safety precautions must you observe
Avoid skin contact with flux
soldering differs from brazing in that soldering
Occurs at low temperature
what is the purpose of hard-face welding? what is the purpose of thermal spraying?
Rebuild worn areas, apply a surface coating
in torch hard facing the new material melts __ the surface. in flame spraying the new material melts __ the surface
Before it reaches; before it reaches
which of the following is common surfacing material
Ceramics
when using thermal spraying for shaft repair which step should be performed first
Machining
