Welding Oral (Odd #'s) Flashcards
Explain the purpose of tack welding.
Holds parts together before they are permanently welded. The parts are assembled, and small spots of weld are placed at strategic locations to hold them in position.
Why is it necessary to use flux in all silver soldering operations?
To ensure the base metal is chemically clean. (The flux removes the film of oxide from the base metal and allows the silver solder to adhere to it.)
When inspecting a butt weld, the weld penetration should be how thick?
The weld penetration should be 100 percent of the thickness of the base metal.
What do the cylinders containing acetylene contain to help stabilize the gas?
The cylinders are packed with a porous material, and then saturated with acetone.
How is the number of beads determined when producing a fillet weld in heavy metals?
By the thickness of the metal being welded.
What is the recommended repair of engine mounts?
By using a larger diameter replacement tube telescoped over the stub of the original member using fish mouth and rosette welds.
What color of glass is used in the protective eyewear designed especially for aluminum oxy-fuel welding?
Green
Name the three types of torches used in gas welding.
Equal pressure, Injector, and Cutting
What purpose does flux serve in welding aluminum?
Remove the oxides from the metal immediately ahead of the weld.
List the protective personal equipment you should use when welding?
Welding helmet, gloves, protective clothing and footwear, and If not in an adequately ventilated area, appropriate breathing equipment.
What should be considered when selecting a filler welding rod?
The filler rod selected should be compatible with the base metal being welded.
What can cause a welding torch to backfire?
A backfire may be caused by touching the tip against the work, overheating the tip, by operating the torch at other than recommended pressures, by a loose tip or head, or by dirt or slag in the end of the tip, and may cause molten metal to be splattered when the flame pops.
Name the two most common fuel gases used for gas welding?
Oxygen and Acetylene.
Why must acetylene gas be kept at 15 psi or below?
Acetylene is chemically very unstable. The acetylene pressure gauge should never be set higher than 15 psi for welding or cutting.
What determines the amount of heat applied to the material being welded in gas welding?
The size of the tip opening determines the amount of heat applied to the work.
