Section II Airframe Structures (Welding)

Question 1

What type of weld joint must be used to weld magnesium?

Answer 1

Only butt welds are used to weld magnesium.

Question 2

Why must all flux be removed from the metal after welding magnesium?

Answer 2

Any flux left on the metal will result in severe corrosion.

Question 3

What must be done in order to successfully weld titanium?

Answer 3

The weld zone must be shielded with an inert gas such as helium or argon.

Question 4

what is gas shielded arc welding?

Answer 4

It results in a stronger, more ductile, and more corrosion resistant weld.

Question 5

What are the advantages of gas shielded arc welding?

Answer 5

A gas is used as a covering shield around the arc to prevent the atmosphere from contaminating the weld.

Question 6

What shielding gases are used for gas tungsten arc (TIG) welding?

Answer 6

Helium and argon.

Question 7

What is an advantage of electric arc welding over gas welding?

Answer 7

Causes less buckling and warping of the welded material.

Question 8

What is meant by a soft flame?

Answer 8

When the torch is adjusted so that the flame makes no noise, and doesn’t push the weld puddle.

Question 9

What determines the amount of heat that will be applied to the work when welding by the oxy-acetylene method?

Answer 9

The size or the diameter of the torch tip

Question 10

when gas welding, what should be turned off first?

Answer 10

“A comes before O” Cut Acetylene off before Oxygen

Question 11

the result of using torch tip that is too large or too small?

Answer 11

If the torch tip is too large, the heat will be too great and holes may be burned in the middle.

If the torch temp is too small, the heat provided may be insufficient to produce penetration to the proper depth causing low strength well.

Question 12

How do you determine the correct size filler rod to be used in welding ?

Answer 12

The thickness of the metals being joined.

Question 13

What is the function of flux when used in soldering?

Answer 13

Flux erodes corrosion from the surface of the metal when it is heated so the solder can form a strong bond.

Question 14

why must acid core solder never be used on electrical wire?

Answer 14

Any acid flux that is left over will cause severe corrosion to the wire.

Question 15

what is brazing?

Answer 15

Metal joining process in which the bonding material is a non-ferrous metal with a melting point lower than that of the metals being used. It can be used to join metals that are damaged by high heat.

Question 16

What is one method of controlling expansion when welding a joint?

Answer 16

By tack welding at intervals along the joint.

Question 17

Why is it especially desirable to use soft flame when welding aluminum?

Answer 17

To avoid blowing holes in the metal when the puddle is formed.

Question 18

What fuel is used for gas welding aluminum?

Answer 18

Oxygen and Hydrogen

Question 19

what is the purpose of using flux when welding aluminum?

Answer 19

Aluminum welding plugs is designed to remove the aluminum oxide by chemically combining with it. Aluminum fluxes dissolve below the surface of the puddle and float the oxides to the surface where they can be removed.

Question 20

What is the maximum safe pressure for acetylene gas when welding?

Answer 20

When acetylene gas is to a pressure greater than 15 psi, it becomes dangerously unstable. At 29.4 psi, acetylene is self explosive and only a slight shot can cause it to ignite.

Question 21

How can dents at a steel tube cluster joint be repaired?

Answer 21

Well they specifically formed steel patch over the dented area and surrounding tubes.

Question 22

What type of flame should be used when silver soldering?

Answer 22

The flame should be neutral.

Question 23

What are procedures preparing a metal fuel tank for welding?

Answer 23

The interior of the tank should be washed with hot water and detergent, and then steamed for a minimum of 30 minutes.

Question 24

When splicing tubing by the inner sleeve method, what method can be used to insert a tight fitting inner sleeve into the replacement tube?

Answer 24

The inner sleeve can be chilled with dry ice or cold water, and the outer sleeve can be heat treated. This will allow for a tighter fit repair.

Question 25

Why is flux used on silver solder?

Answer 25

Cleans the base metal oxide to ensure a good bond.

Question 26

Name three types of welding.

Answer 26

Resistance, arc, gas. ( R.A.G )