SMAW

Question 1

Electrical Circuit

Answer 1

Path taken by electric current flowing from one terminal, through a conductor, to the other terminal

Question 2

Current

Answer 2

Amount of electron flow through an electrical circuit, measured in amps, I x R = V

Question 3

Conductor

Answer 3

Any material through which electricity flows easily, ex: wires, cables, busbars

Question 4

Resistance

Answer 4

Opposition of the material in a conductor to the passage of electric current, causing the electrical energy to be transformed into heat, measured in Ohms

Question 5

Ohm

Answer 5

Basic unit of measure for resistance, I x R = V

Question 6

Direct Current

Answer 6

Electrical current that flows in one direction only, DCEP, DCEN

Question 7

Alternating Current

Answer 7

Electrical current that has alternating positive and negative values, first half-cycle (positive) - current flows in one direction, second half-cycle (negative) - current flows in opposite direction

Question 8

Frequency

Answer 8

Number of cycles (AC sine waves) per second, measured in Hertz (Hz)

Question 9

What frequency does North America operate at?

Answer 9

60 Hz

Question 10

What frequency does Europe operate at?

Answer 10

50 Hz

Question 11

Polarity

Answer 11

Positive or negative state of an object, determines the direction of current flow in DC

Question 12

DCEN

Answer 12

Electrode - negative, workpiece - positive, current flow from electrode to workpiece

Question 13

DCEP

Answer 13

Electrode - positive, workpiece - negative, current flows from workpiece to electrode

Question 14

Voltage

Answer 14

Amount of electrical pressure in a circuit, doesn’t flow, has most effect on height and width of weld deposit

Question 15

Open Circuit Voltage

Answer 15

Voltage produced when welding machine is ON but no welding is being done

Question 16

What is the open circuit voltage of constant current machines?

Answer 16

50-100V

Question 17

Hot Start

Answer 17

Provides an extra boost of current to help establish an arc when using hard to start electrodes

Question 18

Arc Voltage

Answer 18

Working voltage, voltage present after an arc is struck and maintained, 10-35V

Question 19

Constant Current Welding Machine

Answer 19

Welding machine that maintains a relatively constant current over a wide range of welding voltages caused by changes in arc length, manual

Question 20

Arc Blow

Answer 20

Deflection of the welding arc by magnetic forces that occur due to current flow, common problem in DC in corners and near joint ends, results in incomplete fusion and excessive spatter

Question 21

What is the best way to prevent arc blow?

Answer 21

Use AC

Question 22

Undercutting

Answer 22

Creating a groove in the base metal that is not completely filled by weld metal during the welding process

Question 23

What causes undercutting?

Answer 23

Using excessive current, traveling too fast, improper work angle

Question 24

Overlapping

Answer 24

Extending the weld metal beyond the weld toes

Question 25

When does overlapping happen?

Answer 25

When current is set too low and molten metal is deposited without actually fusing into the base metal

Question 26

Transformer

Answer 26

Electrical device that changes AC voltage from one level to another, transforms a high-voltage/low-current input into a safe and useable low-voltage/high-current output

Question 27

Rectifier

Answer 27

Electrical device that changes AC into DC

Question 28

Inverter

Answer 28

Electrical device that changes DC into AC

Question 29

What are the electrode F-groups?

Answer 29

F1: Fast-Fill, F2: Fill-Freeze, F3: Fast-Freeze, F4: Fill-Freeze

Question 30

F1: Fast-Fill Group

Answer 30

High iron powder coating with soft arc and high deposit rates, ex: E7024

Question 31

F2: Fill-Freeze Group

Answer 31

Moderately forceful arc with medium deposition rate, ex: E6013

Question 32

F3: Fast-Freeze Group

Answer 32

Produces a crisp, deep-penetrating arc and a fast-freezing weld bead, ex: E6010

Question 33

F4: Fill-Freeze Group

Answer 33

Produces sound welds with excellent notch toughness and high ductility, ex: E7018

Question 34

What are the 5 essentials of SMAW?

Answer 34

Electrode selection, arc length, current, travel speed, electrode angle

Question 35

Electrode Selection

Answer 35

Electrode type and diameter

Question 36

Arc Length

Answer 36

Distance from the tip of the electrode to the weld pool

Question 37

What happens when arc length is too long?

Answer 37

Unstable arc, large globules, excessive spatter, incomplete fusion

Question 38

What happens when arc length is too short?

Answer 38

Fails to generate enough heat to melt base metal properly, high, uneven beads with irregular ripples, high chance of sticking

Question 39

Arc Length Size

Answer 39

Size = 1 x Diameter of Electrode

Question 40

Current Selection

Answer 40

Correct current (AC, DCEP, DCEN) for a particular electrode must be used

Question 41

What happens when amperage is too low?

Answer 41

Not enough heat to melt the base metal, weld pool is too small, poor fusion, sticking

Question 41

What happens when amperage is too high?

Answer 41

Electrode melts too fast, weld pool is large and hard to control, excessive spatter

Question 42

Travel Speed

Answer 42

Rate at which an electrode moves along a joint

Question 43

Electrode Angle

Answer 43

Combination of travel angle and work angle

Question 44

Travel Angle

Answer 44

Angle less than 90 degrees between the electrode axis and a line perpendicular to the work piece

Question 45

Push Travel Angle

Answer 45

Travel angle where the electrode points toward the direction of travel, less heat input, shallow penetration

Question 46

Drag Travel Angle

Answer 46

Travel angle where the electrode points away from the direction of travel, more heat input, deeper penetration

Question 47

Work Angle

Answer 47

Angle less than 90 degrees in a line perpendicular to workpiece and in a plane determined by the electrode axis and the weld axis

Question 48

Duty Cycle

Answer 48

Percentage of time during a specified period that a welding machine can be operated as its rated load without exceeding the temperature limits of the insulation on the component parts

Question 49

What is the time period NEMA has set the standard for a duty cycle?

Answer 49

A 10 min period

Question 50

What do the first two (and sometimes three) digits of an electrode classification number specify?

Answer 50

The minimum tensile strength of the deposited weld metal in thousands per square inch (ksi), ex: 60 ksi or 60,000 psi

Question 51

What does the third digit of an electrode classification number specify?

Answer 51

Welding position 1 - all positions 2 - flat position groove (1G), fillet welds (1F), horizontal fillet welds (2F) 4 - flat, horizontal, vertical down, overhead

Question 52

What does the last digit of an electrode classification number specify?

Answer 52

Type of coating, welding current, operating characteristics (0-8)