API 577 | QUESTIONS AND ANSWERS | 2026 UPDATE | WITH COMPLETE SOLUTION
How many welds does API 577 require to be radiographed? - (ANSWER)Zero. (The number of welds to
RT is established by the primary code)
Arc Blow - (ANSWER)The deflection of an arc from its normal path because of magnetic forces
Arc Length - (ANSWER)The distance from the top of the welding electrode to the adjacent surface of
the weld pool
Autogenous Weld (one without filler metal) - (ANSWER)A fusion made without filler metal
Backing - (ANSWER)A material or device placed against the backside of the joint, or at both sides of a
weld in welding, to support and retain molten weld metal
Defect - (ANSWER)A discontinuity or discontinuities that by nature or accumulated effect render a
part or product unable to meet minimum applicable acceptance standards or specifications. The term
designated reject ability
Discontinuity - (ANSWER)An interruption of the typical structure of a material, such as a lack of
homogeneity in its mechanical, metallurgical, or physical characteristics. A discontinuity is not
necessarily a defect
Inclusion - (ANSWER)Entrapped foreign solid material, such as slag, flux, tungsten, or oxide
Undercut - (ANSWER)A groove melted into the base metal adjacent to the weld toe or weld root and
left I filled by weld metal
Corrective action of non-conformance - (ANSWER)Action is based on nature of non-conformance
Which welding process is most widely used - (ANSWER)SMAW
, API 577 | QUESTIONS AND ANSWERS | 2026 UPDATE | WITH COMPLETE SOLUTION
Describe the SMAW process - (ANSWER)Arc between covered electrode and weld pool. Heat of arc
comes from tip of a consumable covered electrode. Shielding comes from decomposition of the
electrode coating
Basic functions of the SMAW electrode coating - (ANSWER)1. shielding gas
2. prevent excessive grain growth
3. slag blanket to protect weld
4. sometimes provide alloy elements
Advantages of SMAW - (ANSWER)1. Simple inexpensive and portable
2. Process can be used in areas of limited access
3. Less sensitive to wind and draft
4. Suitable for most common metals and alloys
Limitations of SMAW - (ANSWER)1. Lower deposition rates
2. Slag must be removed from deposited weld passes
Advantages of GTAW - (ANSWER)1. Produces high quality welds
2. Little postweld cleaning
3. Excellent control of root pass
4. With or without filler metal
Limitations of GTAW - (ANSWER)1. Lower deposition rates
2. Has a low tolerance for contamination on filler or base metals
3. Difficult to shield weld zone properly if drafty
Advantages of GMAW - (ANSWER)1. Only consumable electrode process that can be used to weld
commercial metals or alloys
How many welds does API 577 require to be radiographed? - (ANSWER)Zero. (The number of welds to
RT is established by the primary code)
Arc Blow - (ANSWER)The deflection of an arc from its normal path because of magnetic forces
Arc Length - (ANSWER)The distance from the top of the welding electrode to the adjacent surface of
the weld pool
Autogenous Weld (one without filler metal) - (ANSWER)A fusion made without filler metal
Backing - (ANSWER)A material or device placed against the backside of the joint, or at both sides of a
weld in welding, to support and retain molten weld metal
Defect - (ANSWER)A discontinuity or discontinuities that by nature or accumulated effect render a
part or product unable to meet minimum applicable acceptance standards or specifications. The term
designated reject ability
Discontinuity - (ANSWER)An interruption of the typical structure of a material, such as a lack of
homogeneity in its mechanical, metallurgical, or physical characteristics. A discontinuity is not
necessarily a defect
Inclusion - (ANSWER)Entrapped foreign solid material, such as slag, flux, tungsten, or oxide
Undercut - (ANSWER)A groove melted into the base metal adjacent to the weld toe or weld root and
left I filled by weld metal
Corrective action of non-conformance - (ANSWER)Action is based on nature of non-conformance
Which welding process is most widely used - (ANSWER)SMAW
, API 577 | QUESTIONS AND ANSWERS | 2026 UPDATE | WITH COMPLETE SOLUTION
Describe the SMAW process - (ANSWER)Arc between covered electrode and weld pool. Heat of arc
comes from tip of a consumable covered electrode. Shielding comes from decomposition of the
electrode coating
Basic functions of the SMAW electrode coating - (ANSWER)1. shielding gas
2. prevent excessive grain growth
3. slag blanket to protect weld
4. sometimes provide alloy elements
Advantages of SMAW - (ANSWER)1. Simple inexpensive and portable
2. Process can be used in areas of limited access
3. Less sensitive to wind and draft
4. Suitable for most common metals and alloys
Limitations of SMAW - (ANSWER)1. Lower deposition rates
2. Slag must be removed from deposited weld passes
Advantages of GTAW - (ANSWER)1. Produces high quality welds
2. Little postweld cleaning
3. Excellent control of root pass
4. With or without filler metal
Limitations of GTAW - (ANSWER)1. Lower deposition rates
2. Has a low tolerance for contamination on filler or base metals
3. Difficult to shield weld zone properly if drafty
Advantages of GMAW - (ANSWER)1. Only consumable electrode process that can be used to weld
commercial metals or alloys
