welding

Question 1

What is flux, what does it do

Answer 1

substance that prevents. dissolves and facilitates removal of oxide formation and other contaminants in welding

Question 2

three benefits of flux

Answer 2

1) provides protective atmosphere for welding
2) stabilizes arc
3) reduces spattering

Question 3

What is the consumable in Gas Metal Arc Welding?

Answer 3

electrode (bare metal wire) with shielding by flooding the arc with an inert gas (i.e. MIG welding)

Question 4

what’s meant by a consumable

Answer 4

materials used up and need to be regularly replaced during welding, essential to create weld joint and protect weld area

Question 5

components of gas metal arc welding

Answer 5

a liner, contact tip, gas nozzle, and diffuser.
These parts feed the filler wire, maintain the gas shield, and create a good welding arc

Question 6

2 types of joining

Answer 6

welding
soldering
adhesive bonding

Question 7

what does a joining process entail

Answer 7

forming permanent joints between parts

Question 8

what’s an assembly

Answer 8

mechanical fastening parts together

Question 9

2 major categories of welding

Answer 9

fusion and solid-state

Question 10

what’s solid-state welding

Answer 10

uses pressure or combination of heat and pressure

Question 11

when heat is used in solid state welding, temperature is {1} the welded metal’s melting point

Answer 11

1: below

Question 12

True of False:
Filler metal is added to solid state welding

Answer 12

False

Question 13

what’s fusion wleding

Answer 13

Heating two or more materials to their melting point or above, fuse together, strong permanent bond

Question 14

An example of fusion welding

Answer 14

arc welding
resistance welding
oxyfuel gas welding

Question 15

describe the process of arc welding

Answer 15

melting two metals together using electricity to create intense heat.
heat produced by an electric arc formed between the workpiece and an electrode.

Question 16

describe oxyfuel welding

Answer 16

process using high-heat, high-temperature flame produced by burning a fuel gas (most commonly acetylene) mixed with pure oxygen

Question 17

flame type used in oxyfuel welding

Answer 17

neutral flame

Question 18

how is friction welding achieved

Answer 18

rotating part in contact with stationary part, generates friction, until rotation stops; axial pressure applied, weld created

Question 19

what kinds of welding defects can occur?

Answer 19

incomplete/lacking penetration weld and concave beads; leads to cracking

Question 20

A concave bead is a type of { 1 } that has a depressed/ {2} center, giving it a concave shape. This profile is achieved by controlling the {3} input, often by reducing the voltage or current, or using a smaller {4}. Concave beads are known for providing excellent {5} into the base metal, making them useful for welding {6} materials. However, they can be more challenging to control and are generally not as {7} as convex beads.

Answer 20

1: welding bead
2: indented
3: heat
4:electrode
5: penetration
6: thin
7: strong

Question 21

In arc welding, a pool of { 1 } is formed near electrode tip, as the electrode is moved along the joint, { 2 } pool {3} in its wake.

Answer 21

1: molten metal
2:molten weld
3: solidifies

Question 22

consumable meaning

Answer 22

consumed during welding process

Question 22

what’s a nonconsumable, give an example

Answer 22

not consumed during welding process, e.g. Tungsten

Question 22

True or False:

In Arc welding, filler metal must not be separately added

Answer 22

False

Question 23

In arc welding, at high temperatures, metals are chemically reactive to { 1.0,1.1 ,1.2 } in the air. These reactions cause {2} properties of the joint to {3}.

Answer 23

1: oxygen, nitrogen, hydrogen 2: mechanical 3: degrade

Question 24

purpose of arc shielding

Answer 24

to protect the operation by shielding arc from surrounding air

Question 25

2 shielding gases used in arc shielding, and the other component:

Answer 25

Argon, Helium, CO2 flux

Question 26

what's a flux? (in context of arc shielding)

Answer 26

substance preventing, dissolving, and facilitating removal of, oxide formation (and other contaminants) in welding

Question 27

what does a flux do

Answer 27

provides protective atmosphere for welding, stabilizes arc, reduces spattering

Question 28

give an application of a flux

Answer 28

1) stick electrode coated with flux material that melts during welding to cover operation 2) tubular electrodes in which flux is contained in the core, and released as electrode consumed

Question 29

2 consumable electrode arc welding processes...

Answer 29

flux cored arc welding shielded metal arc welding gas metal arc welding

Question 30

what does shield metal arc welding use

Answer 30

consumable electrode, consisting of filler metal rod coated with chemicals to provide flux and shielding

Question 31

In shield metal arc welding, for the welding stick, the composition of the filler metal is close to the { 1 }. The coating is { 2 } mixed with {3} and {4}, held together by a silicate {5}

Answer 31

1: base metal 2: powdered cellulose 3, 4: oxides, carbonates 5: binder

Question 32

2 disadvantages of stick welding

Answer 32

1: sticks must be periodically changed 2: high current levels may prematurely melt coating

Question 33

applications of smaw (steel metal arc welding)

Answer 33

used for steels, stainless steels, cast irons, some nonferrous alloys