TPC 418 Gas Welding Process Flashcards
In oxy fuel welding, you can control the rate of heat input to the base metal by varying the
Angle of the torch
Dipping of the Filler rod
Setting of the gas regulator
Speed of the torch
Speed of the torch 
In torch brazing, the filler metal is distributed in the joint as a result of
Capillary action
Gravity
Heat
Pressure
Capillary action
The purpose of using a flux in welding and brazing is to
Clean the base metal
Lower the melting point of the filler metal
Lubricate the joint
Prevent the base metal from melting
Clean the base metal
The purpose of postheating is two
Eliminate the need for a flux
Lower the welding temperature
Reduce stresses in the welded structure
Speed up the welding process
Reduce stresses in the welding structure
When you weld low-carbon steel, you should
Dip the filler rod into the weld puddle
Keep the flame well away from the weld puddle
Use a flux
Use an oxidizing flame
Dip the filler rod into the weld puddle
When welding aluminum, you need to remember that aluminum
Begins to glow just before it melts
Conducts heat away from the weld site rapidly
Does not require preheating or post heating
Melts at a higher temperature than most metals
Conducts heat away from the weld site rapidly
In preparing aluminum parts for welding, you should______ the surfaces to be welded
Burnish
Grease or oil
Scrape or file
Use carbon tetrachloride to clean
Scrape or file
When welding brass, you should use a
Copper filler rod
Flux
Reducing flame
Zinc, filler rod
Flux 
What kind of flame should be used when welding lead?______nickel? _______Magnesium.?_______
Carburizing; Neutral; neutral
Neutral; carburizing; carburizing
Oxidizing; carburizing; neutral
Oxidizing; oxidizing; carburizing
Nutral; carburizing; carburizing
To make the best possible welds using oxyfuel equipment, you should
Know what metals you are joining
Move the filler rod in and out of the flame
Quench the welded part it in water immediately
Use a neutral flame unless directed otherwise
Know what metals you are joining
Oxyfuel welding and oxygen cutting are alike in that both processes
Produce a kerf
Require lighting the torch with a sparklighter
Result in combustion of the base metal
Use a torch that delivers a stream of oxygen
Require lighting the torch with a sparklighter
Which of the following must be worn during an oxygen cutting operation?
Face shield
Goggles with dark lenses
Leggings
Skull cap
Goggles with dark lenses 
When piercing a steel plate with an oxygen cutting torch, which step should be performed first?
Blow the slag away from you
Cut a kerf from the edge to the spot
Heat the spot to a bright red
Open the cutting oxygen valve
Heat the spot to a bright red
The purpose of scarfing is to
Create a groove in a metal piece
Pierce a hole in a metal sheet
Remove a surface defect from unfinished steel
Remove excess metal from a casting
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 it difficult job easier if you
Decrease the amount of preheating
Lay a bead of low-carbon steel along the cut line
Make a cut in short segments
Use a helper with a second torch
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
Braze welding
Brazing
Fusion welding
Turning
Brazing
The purpose of using a flux in brazing is to
Control the flow of the filler metal
Eliminate oxides from the metal surfaces
Lower the melting point of the base metal
Protect the surface of the metal after brazing
Eliminate oxides from the metal surfaces
A special concern when brazing ______ is that the filler metal melts at a temperature very near the melting point of the base metal
Aluminum
Cast-iron
Malleable iron
Stainless steel
Aluminum
When brazing and braze welding, which of the following safety precautions must you observe?
Avoid skin contact with the flux
Do not create sparks in the area
Seal chemical containers before working on them
Wear a full face shield
Avoid skin contact with the flux
Soldering differs from brazing in that soldering
Does not require melting the base metal
Occurs at higher temperatures
Occurs at lower temperatures
Requires melting the base metal
Occurs at lower temperatures
What is the purpose of hard face welding? What is the purpose of thermal spraying?
Apply a surface coating; join flat surfaces
Apply a surface coding; rebuild worn areas
Join flat surfaces; rebuild areas
Rebuild worn areas; apply a surface coating
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.
After it is placed on; after it is placed on
After it is placed on; before it reaches
Before it reaches; after it is placed on
Before it reaches; before it reaches
Before it reaches; before it reaches
Which of the following is a common surfacing material?
Carbon
Ceramics
Glass
Thermoplastics
Ceramics
When using thermal spraying for Shaft repair, which step should be performed first?
Cleaning
Machining
Surfacing
Undercoating
Machining
Electric arc spring operations require eye protection with a lens shade number of
1 to 3
1 to 5
6 to 8
9 to 10
9 to 10
