Chapter One Exam

Question 1

Components of GTAW gun are?

Answer 1

Nozzle, collet, collet body, back cap and gas valve.

Question 2

Common FCAW application is?

Answer 2

Vertical up of thick plate.

Question 3

Can GMAW use a constant voltage as well as constant current power source?

Answer 3

Yes.

Question 4

Welding arc consists of what?

Answer 4

High current low voltage.

Question 5

The strength of the magnetic field, the pinch effect depends mostly on what?

Answer 5

Current density.

Question 6

Soldering uses a filler metal that melts below what temperature?

Answer 6

450C.

Question 7

SAW fluxes that highly influence composition of weld metal through slag and metal reactions is what?

Answer 7

Active.

Question 8

GTAW electrodes can be ground to a cone. What does a large vertex angle on a weld bead do?

Answer 8

Bead width decreases.

Question 9

Do fluxes for soldering replace pre cleaning?

Answer 9

No.

Question 10

What kind of flux for critical applications of SAW?

Answer 10

Basic.

Question 11

For EBW, heat required for welding is supplied by what?

Answer 11

Accelerated negative charged particles.

Question 12

Key factors affect performance of GMAW power source for semi automated?

Answer 12

Slope and inductance.

Question 13

When an arc is formed between two electrodes what happens with electricity?

Answer 13

Electricity flows from negative cathode to positive anode.

Question 14

What method is used to solder multiple components onto an electrical circuit board?

Answer 14

Wave.

Question 15

Self shielded flux cored wires are what?

Answer 15

Better able to tolerate air currents.

Question 16

SAW method that has multiple arrangements and current path is from one electrode to the other through a weld pool?

Answer 16

Series arc welding.

Question 17

CSA standard W48, E491T-9MJ-H8 wire is:

Answer 17

8ml of diffusible hydrogen per 100g of weld metal.

Question 18

Modern inverter for GTAW uses different methods of arc starting except for what?

Answer 18

Steel wool.

Question 19

Why does electroslag process produce welds with poor mechanical properties?

Answer 19

Large grain and HAZ.

Question 20

What metals can be easily brazed?

Answer 20

Copper and nickel.

Question 21

Electrodes represented by: EXX15, 16, 18 have what major ingredient in the coating?

Answer 21

Limestone.

Question 22

Contact to tip work distance what?

Answer 22

Contact to tip work distance increase the resistance increase.

Question 23

SAW fluxes are classified how?

Answer 23

Classified in conjunction with the welding wire and forming flux wire.

Question 24

Welding power sources are broadly classified as?

Answer 24

Constant current and variable voltage? NO current, shielding gas, voltage? NO
Constant current or constant voltage?

Question 25

Flash welding is a RSW process that involves what?

Answer 25

High current DC power source and high pressure?NO High current and low pressure until melting than high pressure?

Question 26

GTAW can be used with what polarity?

Answer 26

AC and DC.

Question 27

Electroslag process is best described as what?

Answer 27

A vertical process that relies on resistance heating of a molten slag bath.

Question 28

For the SAW process, what does not happen when increase of deposition happens?

Answer 28

Low arc voltage.

Question 29

Advantage of GMAW pulsed transfer?

Answer 29

Reduced heat input while maintaining similar deposition rate and penetration.

Question 30

Thermite welding is?

Answer 30

Exothermic chemical reaction generating heat to melt the weld metal.

Question 31

Explosion welding is?

Answer 31

A solid state process, coalescence is produced through high speed impacting of two or more materials by controlled detonation.

Question 32

What is the arc efficiency for SAW?

Answer 32

90 to 95.

Question 33

When the electrode tip melts in GMAW, what are the forces that act on the molten tip?

Answer 33

Surface tension, gravity, plasma jet, electromagnetic pinch force.

Question 34

Laser is an acronym for what?

Answer 34

Light amplification by stimulated emission of radiation.

Question 35

GMAW uses?

Answer 35

Constant voltage power supply resulting in an increase in current.

Question 36

FCAW is a process that is usually semi automated consisting of what?

Answer 36

Constant voltage, continuous speed wire, welding gun, continuous filler, hollow core containing flux and other ingredients.

Question 37

Advantage of brazing?

Answer 37

Low distortion and residual stresses.

Question 38

Flat weld profile, good penetration using MCAW you can do what with the angle and technique?

Answer 38

15 angle and push technique.

Question 39

Big advantage of EBW?

Answer 39

Weld thick sections in one pass.

Question 40

What type of laser is best suited for robotic welding applications?

Answer 40

Fibre.

Question 41

GMAW higher productivity compared to SMAW is partially due to what?

Answer 41

Higher duty cycle.

Question 42

Welding using the GTAW process with current at DCEN results in what?

Answer 42

30 at electrode 70 at work.

Question 43

Disadvantage of DCEN compared to DCEP in SAW process?

Answer 43

Incomplete penetration.

Question 44

Hydrogen added to shielding gas can be used to weld what?

Answer 44

Austenitic stainless steels.

Question 45

SAW process can be used in what polarity?

Answer 45

Constant voltage or current.

Question 46

SMAW coating is used for?

Answer 46

Gas shield, slag covering, scavengers, arc stability, and adding alloying elements.

Question 47

Components of SMAW?

Answer 47

Electrode holder, ground cable, CC power.

Question 48

RSW is used for what type of joint often?

Answer 48

Lap joint.

Question 49

Problem with excess penetration in SAW is?

Answer 49

Solidification cracking.

Question 50

What wire provides best notch toughness for FCAW?

Answer 50

Basic.

Question 51

RSW is continuous or non continuous seam joint welding between faying surfaces? Yes or no?

Answer 51

Yes.

Question 52

Components of GMAW gun?

Answer 52

Nozzle, contact tip, gas diffuser, liner, and trigger.

Question 53

Main advantage of GTAW?

Answer 53

High quality weld and ability to weld almost all metals.

Question 54

GMAW spray transferred achieved by?

Answer 54

High current and voltage with argon rich.

Question 55

Welding position for ESW?

Answer 55

Vertical up.

Question 56

Resistance spot welding is? Current, travel, voltage high?

Answer 56

Welding current is high.

Question 57

Electrodes for FCAW is?

Answer 57

Can be self or gas shielded.

Question 58

SMAW power source is?

Answer 58

Constant current and constant voltage.

Question 59

GMAW to produce flat fillet face in horizontal position what is used?

Answer 59

20 travel using push and 45 work angle.

Question 60

GMAW uses what gas?

Answer 60

Inert and active gas mixture.

Question 61

MCAW does what with weld metal and gas?

Answer 61

Remove scavs, add iron powder, aide weld deposit, adjust chemistry by adding alloying elements, control puddle fluidity.

Question 62

Biggest disadvantage of ESW?

Answer 62

Large grain and haz.

Question 63

Diffusion welding is?

Answer 63

Solid state process that produces atomic bond between two surfaces through heat and pressure.

Question 64

What polarity is highest deposition with SAW?

Answer 64

DCEN.

Question 65

Two types of fluxes for SAW?

Answer 65

Fuse and bonded.

Question 66

SMAW process using DCEP results in max heat generated at what?

Answer 66

At the cathode.

Question 67

EBW process developed for what originally?

Answer 67

Weld refractory and reactive materials.

Question 68

Voltage drop across the arc is greatest at what point?

Answer 68

Cathode and anode drop zones.

Question 69

What is the advantage of PAW over GTAW?

Answer 69

Higher productivity? NO. All of above? greater thicknesses? NO

Question 70

Fluxes for SAW is?

Answer 70

When molten, provide current path to sustain arc.

Question 71

Primary control on SMAW process?

Answer 71

Current.

Question 72

FWR process involves what for polarity?

Answer 72

High current and low pressure until melting occurs then high pressure.

Question 73

Can GMAW use constant voltage as well as constant power current source?

Answer 73

Yes.

Question 74

Stages of diffusion welding?

Answer 74

Deformation of surface roughness. Diffusion of atoms from one grain to another. Volume diffusion of atoms to voids.

Question 75

Welding using GMAW current set to DCEP results in what percentages?

Answer 75

30 electrode and 70 at work.

Question 76

Welding arc consists of?

Answer 76

High current low voltage.

Question 77

For SAW what polarity provides better control over bead shape and deeper penetration?

Answer 77

DCEP.

Question 78

Melting rate of SMAW is dependent on?

Answer 78

Voltage? NO Arc length? No. probably current

Question 79

GTAW with DCEP is mostly used for what materials?

Answer 79

Carbon and stainless steels.

Question 80

Explosion welding is typically used for what?

Answer 80

Clad metals onto carbon or SS.

Question 81

Fluxes that significantly influence weld comp is what?

Answer 81

Active.

Question 82

What would not result in an increase of deposition rate for SAW?

Answer 82

Increase contact tip to work distance? NO

Question 83

Two advantages of LBW process?

Answer 83

Easily automated and produces narrow welds.

Question 84

Electricity flows from where when an arc is formed from two electrodes?

Answer 84

Electricity flows from negative cathode to positive anode.

Question 85

PAW process involves what?

Answer 85

Non consumable electrode with an orifice to constrict the arc.

Question 86

Weld integrity for RSW is usually what method?

Answer 86

Pulling the joint apart.

Question 87

What GTAW process assists in cleaning and removal of oxides?

Answer 87

DCEP.

Question 88

Main disadvantage of FCAW compared to GMAW?

Answer 88

Amount of fume generation.

Question 89

Friction welding is accomplished by?

Answer 89

Relative motion of parts that produces an upset.

Question 90

Resistance spot welding current is what?

Answer 90

High.

Question 91

Maximum amount of heat is generated at the point of maximum resistance for resistance welding?

Answer 91

Yes.

Question 92

Electroslag process biggest disadvantage?

Answer 92

Large grains for weld metal and HAZ.

Question 93

Primary variables of GMAW are?

Answer 93

Current, voltage and shielding gas? NO.

Question 94

RSW polarity is?

Answer 94

High current.

Question 95

GTAW tip of shape of cone, what is effect of large vertex angle on weld penetration?

Answer 95

Penetration increase.

Question 96

Common applications of GMAW?

Answer 96

Miscellaneous metals such as stairs and railings.

Question 97

MCAW AWS A5.36 groups the wires with?

Answer 97

FCAW and GMAW.

Question 98

PAW process for keyhole plasma has a current range of greater than?

Answer 98

100A.

Question 99

Plasma arc process involves what?

Answer 99

Non consumable electrode with an orifice to constrict the arc.

Question 100

GMAW uses?

Answer 100

Constant voltage, results in increase of current.