Chapter 16 GTAW and FCAW

Question 1

___________________ rolls are used for solid GMAW electrodes and some metal cored applications.

Answer 1

smooth v-groove

Question 2

_______________ rolls are used for flux cored and some metal cored electrodes.

Answer 2

knurled v-groove

Question 3

______________ rolls have ridges in the groove to grip and push the electrode wire.

Answer 3

knurled

Question 4

Aluminum wire is fed with __________ rolls

Answer 4

smooth u-groove

Question 5

The wire feeder is the same for all electrodes but the __________ are changed based on the type of the electrode wire.

Answer 5

drive rolls

Question 6

When the electrode diameter changes, the _____________ must also be changed.

Answer 6

drive rolls

Question 7

In FCAW, what should you do if the wire exiting the gun is crushed or deformed?

Answer 7

That means the pressure is too high. Reduce the pressure and check again.

Question 8

When the wire in the feeder becomes tangled it produces a _____________.

Answer 8

bird’s nest

Question 9

How do you remove a bird’s nest?

Answer 9

By raising the pressure roll and cutting the wire on both sides of the bird’s nest

Question 10

What part of the welding gun need to be replaced most often?

Answer 10

The contact tube

Question 11

How is the contact tube replaced?

Answer 11

Select the correct size contact tube for the diameter of electrode you will use. The contact tube is threaded into the adapter or diffuser.

Question 12

The hole in the center of the contact tube will get _______ due to wear.

Answer 12

larger

Question 13

________ hours of constant welding with a steel electrode will wear a contact tube enough that it will need to be replaced.

Answer 13

eight

Question 14

What does the AWS GMAW designation E mean?

Answer 14

E stands for electrode
It means a filler material can be used as an electrode

Question 15

What does the AWS GMAW designation R mean?

Answer 15

R stands for rod

Question 16

In the AWS designation, after the E and R the next set of numbers is the ________ of the weld wire after welding.

Answer 16

tensile strength

Question 17

The tensile strength is measured in _________

Answer 17

thousands of pounds per square inch

Question 18

Typical value in the electrode designation for carbon steel electrodes are ____ and _____

Answer 18

70 and 80 which represents
70,000 and 80, 000 psi

Question 19

High-strength steels may require electrodes with tensile strengths of ______

Answer 19

90, 100, 110 or more

Question 20

In the AWS designation for GMAW, after the E, R and tensile strength comes a letter, either ____ or ____.

Answer 20

S or C

Question 21

What does the AWS GMAW designation S mean?

Answer 21

Identifies the material as a solid electrode wire

Question 22

What does the AWS GMAW designation C mean?

Answer 22

Identifies the material as a metal cored electrode.

Question 23

What does the AWS designation for FCAW, what does T mean?

Answer 23

Tubular electrode

Question 24

Carbon steel electrodes from GMAW are given different dash numbers to identify their varying compositions. A common GMAW electrode for carbon steel is _________

Answer 24

ER70S-6

Question 25

FCAW electrodes have a dash number which indicates which three pieces of information about the electrode?

Answer 25

1. The polarity to use 2. The shielding gas to use, if required 3. Whether the electrode can be used for multiple-pass welds.

Question 26

What is a dash number?

Answer 26

Numerals or letters at the end of the electrode designation, following a dash.

Question 27

The tension adjusting knob should be adjusted to apply the _____________ pressure needed to properly feed the electrode wire.

Answer 27

minimum

Question 28

True or False: It is important not to crush flux cored wires.

Answer 28

True

Question 29

Common GMAW and cored electrode diameters range from ___________

Answer 29

0.030" to 1/16" (0.8 mm to 1.6 mm)

Question 30

Common FCAW electrodes range from _________

Answer 30

0.045" to 1/16" (1.2 mm to 1.6 mm)

Question 31

soft electrodes such as _______________ and ________________ electrodes cannot be pushed through a welding cable as far as a large-diameter electrode.

Answer 31

aluminum and magnesium

Question 32

There are two settings on the welding machine which must be adjusted. What are they?

Answer 32

1. voltage 2. wire feed speed The metal transfer method is set by these two variables and the shielding gas selected.

Question 33

What does adjusting the voltage and wire feed speed do?

Answer 33

determines the arc length and current

Question 34

What should the wire speed setting be for a carbon or low-alloy steel 0.035" electrode using short circuiting transfer?

Answer 34

160-380 in/min (4.1 - 9.7 M/min)

Question 35

What should the voltage setting be for a carbon or low-alloy steel 0.035" electrode using short circuiting transfer?

Answer 35

16-22 V

Question 36

What should the wire speed setting be for a carbon or low-alloy steel 0.035" electrode using spray transfer?

Answer 36

360-520 in/min ( 9.1 - 13.2 M/min)

Question 37

What should the current setting be for a carbon or low-alloy steel 0.035" electrode using spray transfer?

Answer 37

24-28 V

Question 38

Flux cored electrodes are designed for one of two position groupings. They may be designed to be used in the flat position to make __________________ or they may be designed to ______________

Answer 38

horizontal fillet welds weld in all positions

Question 39

Electrodes for FCAW used for welding in flat positions and horizontal fillet welds are designated by a _____. Those used for welding in all positions are designated by a _____. These are followed by the letter ____

Answer 39

0 1 T

Question 40

The electrode E70T-X is for use in which position?

Answer 40

Flat or horizontal fillet weld

Question 41

The electrode E81T-X is for use in which position?

Answer 41

All positions

Question 42

Gas-shielded flux cored electrodes can be designed to work with 100% ____ or with an _________ mixture.

Answer 42

CO2 argon-CO2

Question 43

To identify which type of shielding gas is to be used with the electrode, a ____ is added to the designation for CO2 and a _____ is added for mixed gas.

Answer 43

C M

Question 44

Which type of shielding gas should be used with the electrode E71T-1C

Answer 44

CO2

Question 45

Which type of shielding gas should be used with the electrode E71T-1M

Answer 45

Mixed gas

Question 46

When a single electrode can be used with either shielding gas, it is identified with _____________

Answer 46

Both designations C and M For example E71T-1M and E71T-1C

Question 47

How many drive rolls are in a FCAW?

Answer 47

Wire feeders use a 2 roll drive system which works well with welding rolls up to 15 feet long. A 4 roll drive system is used for up to 25 feet.