Flux Cored Arc Welding Quiz

Questions and Answers

What does FCAW stand for?

Flux Cored Aluminum Welding

Flux Core Arc Welding

Fluxed Core Arc Welding

Flux Cored Arc Welding (correct)

What does the term FCAW-S mean?

Self-shielded flux cored process

What does the term FCAW-G mean?

Gas shielded flux cored process

What metals are often welded using FCAW?

Carbon, alloy steels, and stainless steels Signup and view all the answers

What gas or gas mixtures are commonly used for FCAW?

CO2 or a mixture of Argon CO2 Signup and view all the answers

A flux cored electrode that protects the weld zone from contaminants with fluxing elements released from the core wire is called:

self-shielded Signup and view all the answers

Describe the two FCAW processes commonly used?

Gas shielded and self shielded Signup and view all the answers

Which of the 2, Gas-shielded or Self-shielded, is the electrode stick-out most important, why?

Self shielded. Can have an electrode stick out of 3" or more Signup and view all the answers

In the AWS electrode classification EXXT-X, what does E stand for?

E is current carrying electrode Signup and view all the answers

In the AWS classification designators E7XT-X, what does the 7 stand for?

70,000 psi minimum tensile strength Signup and view all the answers

In the AWS classification designators E71T-X, what does the 1 stand for?

Welding positions/all positions Signup and view all the answers

In the AWS classification designators E70T-X, what does the 0 stand for?

Welding positions/flat and horizontal fillets Signup and view all the answers

In the AWS electrode classification E71T-1, what does the digit after the dash designate?

chemical composition Signup and view all the answers

In the AWS classification designators EXXT-X, what does T stand for?

Tubular electrode/flux cored Signup and view all the answers

Which polarity is most often used with gas shielded wires?

Reverse Polarity Signup and view all the answers

Can DC straight polarity be used for FCAW?

Yes for some self shielded wires Signup and view all the answers

To change from 0.035 GMAW to 0.045 FCAW what would you have to change?

The contact tip and drive rolls Signup and view all the answers

What electrode extension is commonly used for 0.045 FCAW-G?

3/8 to 3/4 Signup and view all the answers

How are FCAW gun/hose/cable assemblies rated?

current carrying capacity Signup and view all the answers

List the guidelines used to consider when selecting an FCAW power source:

rated output, duty cycle, process capability Signup and view all the answers

How are welding power sources rated?

By their amperage, voltage, and duty cycle Signup and view all the answers

What does the wire feed speed control influence?

Amperage Signup and view all the answers

What does a voltage sensing wire feeder have that constant speed control does not have?

A pick-up lead for sensing voltage Signup and view all the answers

Explain what happens when the arc is shortened with a voltage sensing wire feeder:

Produces less voltage, slowing down the wire feeder Signup and view all the answers

What type of drive rolls are used with FCAW?

Knurled Signup and view all the answers

What does voltage do in the welding circuit?

Voltage is the force that overcomes resistance to allow amperage flow Signup and view all the answers

What does amperage control in the welding circuit?

The amount of current flow Signup and view all the answers

Explain the 2/3's 1/3 ratio in the welding circuit:

Depending on the polarity, 2/3's of the arc energy is located either on the base metal or the electrode Signup and view all the answers

Describe DCRP:

Direct current reverse polarity Signup and view all the answers

What polarity is generally used for gas shielded FCAW?

DCEP (reverse polarity) Signup and view all the answers

What polarity is generally used for self shielded FCAW?

DCEN (Straight Polarity) Signup and view all the answers

What effect do variations in the electrode extension have?

Decreasing or increasing welding current Signup and view all the answers

What electrode extension is recommended for 0.045 gas shielded FCAW?

3/8 to 3/4 Signup and view all the answers

What electrode extension is recommended for 0.045 self shielded FCAW?

3" or more Signup and view all the answers

What shielding gas/mixture may be used on mild steels?

C25 75% argon 25% CO2 Signup and view all the answers

What advantage does CO2 have over C25?

Lower cost, deeper penetration Signup and view all the answers

What advantages may be expected when using C25 compared to CO2 on mild steels?

Minimal spatter, high tensile strength Signup and view all the answers

Does the flux cored arc welding process produce slag similar to SMAW?

True Signup and view all the answers

What is the rule of thumb for gun travel? (push or drag)

If there's slag, you drag Signup and view all the answers

Brief description of Rutile core wires

Good operational and positional capabilities, with easy slag removal Signup and view all the answers

Brief description of Basic Core wires

Have a limestone/fluorspar flux core, arc transfer is globular Signup and view all the answers

List the functions of the flux in FCAW:

Provides de-oxidizers, form a slag protective cover, add alloying elements Signup and view all the answers

What influences the choice of filler metal?

Base metal chemistry, shielding gas used, type of metal transfer Signup and view all the answers

What criteria is used to choose the correct wire size?

Melting rate, penetration, material thickness Signup and view all the answers

List the advantages of FCAW over other processes:

Good weld appearance, up to 4x greater deposition rate than SMAW, less distortion Signup and view all the answers

List the disadvantages of FCAW over other processes:

Slag removal necessary, limited to welding ferrous materials, more costly Signup and view all the answers

Why must the slag be removed between passes on a multi-pass weld?

Slag entrapment Signup and view all the answers

When using a weave technique for FCAW, you can eliminate undercut by:

Stopping momentarily at the end of each weaving motion. Signup and view all the answers

Identify FCAW terms used to describe tubular wire, contact tube (contact tip), arc and metal transfer, shielding gas.

Signup and view all the answers

Study Notes

Flux Cored Arc Welding (FCAW)

FCAW stands for Flux Cored Arc Welding, a welding process that uses a continuously fed tubular wire filled with flux.

Types of FCAW

FCAW-S refers to self-shielded flux cored processes that do not require external gas.
FCAW-G refers to gas shielded flux cored processes which utilize external shielding gas for protection.

Common Applications and Materials

Frequently used to weld carbon, alloy steels, and stainless steels.
Common shielding gases include CO2 or a mixture of Argon and CO2.

Electrode Characteristics

A self-shielded flux cored electrode releases fluxing elements to protect the weld zone from contaminants.
Knurled drive rolls are used with FCAW to grip the wire effectively.

AWS Classification Designators

The letter 'E' indicates that it is a current-carrying electrode.
The number '7' signifies a minimum tensile strength of 70,000 psi.
The number '1' in E71T-X denotes suitability for all welding positions.
The number '0' in E70T-X indicates the application is limited to flat and horizontal positions.
The letter 'T' represents a tubular or flux cored electrode.

Polarity in FCAW

Reverse polarity (DCEP) is standard for gas shielded wires.
DC straight polarity (DCEN) may be used for certain self-shielded wires.
The significance of electrode extension varies, with 3" or more being typical for self-shielded FCAW.

Power Source and Wire Feed Controls

FCAW power sources are rated by amperage, voltage, and duty cycle.
Wire feed speed control impacts amperage, while voltage sensing feeders have additional sensing capabilities to maintain consistent voltage.

Welding Procedures and Techniques

A 2/3's 1/3 rule applies, stating the arc energy distribution can differ based on polarity.
Slag removal between passes is crucial to prevent slag entrapment in multi-pass welds.

Gas and Flux Considerations

C25 (75% Argon, 25% CO2) provides benefits like minimal spatter and high tensile strength compared to pure CO2, which is less costly but offers deeper penetration.
The flux's role includes providing de-oxidizers, forming a protective slag, and adding alloying elements as necessary.

Advantages and Disadvantages

FCAW offers advantages like good weld appearance, high deposition rates (up to 4 times greater than SMAW), and less distortion.
Disadvantages include the need for slag removal, limitations to ferrous materials, and higher costs compared to some other welding processes.

Additional Techniques

Employing a weave technique can help eliminate undercut by briefly pausing at the end of each weaving motion during the welding process.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on Flux Cored Arc Welding (FCAW) with this interactive quiz. You'll learn about key terms, processes, and metals commonly welded using FCAW. Perfect for welding students or professionals looking to refresh their skills.