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Question 1

Score: 0/0

Which welding process uses a consumable, flux-coated electrode and is commonly called stick welding in refinery fabrication?

Gas tungsten arc welding (GTAW)

Shielded metal arc welding (SMAW)

Submerged arc welding (SAW)

Gas metal arc welding (GMAW)

to track

2026 Statistics

Key Facts: API 577 Exam

110 Qs

Exam Questions

100 scored + 10 pretest

3h 15m

Time Limit

Closed-book

~70%

Passing Score

Set scaled score

$380-$440

Exam Fee

Member / non-member

API RP 577 3rd Ed

Reference

October 2020

3 years

Certification Term

Recertification required

The API 577 exam contains 110 multiple-choice questions (100 scored + 10 unscored pretest) delivered in a 3 hour 15 minute closed-book session at a Prometric center or via remote proctoring. The passing score is a set scaled score corresponding to roughly 70% correct. The fee is $380 for API members and $440 for non-members. Questions are based on API RP 577, 3rd Edition (October 2020) and ASME BPVC Section IX Part QW. Prerequisites: any current API 510/570/653 holder qualifies automatically, otherwise 1-5 years of petrochemical experience depending on education. Certification is valid for 3 years.

Sample API 577 Practice Questions

Try these sample questions to test your API 577 exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1Which welding process uses a consumable, flux-coated electrode and is commonly called stick welding in refinery fabrication?

A.Gas tungsten arc welding (GTAW)

B.Shielded metal arc welding (SMAW)

C.Submerged arc welding (SAW)

D.Gas metal arc welding (GMAW)

Explanation: Per API RP 577 Section 5.2, shielded metal arc welding (SMAW) uses a solid consumable electrode covered with a flux coating that melts to form a protective slag and shielding gas. It is one of the most widely used processes in refinery repair because the equipment is portable and tolerant of field conditions. SMAW is also commonly called stick welding. Exam tip: commit the acronyms SMAW, GTAW, GMAW, FCAW, SAW and PAW to memory on day one - they appear throughout the closed-book exam.

2In GTAW, which electrode material is used and is generally alloyed with oxides such as thoria, ceria or lanthana to improve arc starting?

A.Copper

B.Graphite

C.Tungsten

D.Molybdenum

Explanation: Gas tungsten arc welding uses a non-consumable tungsten electrode per API RP 577 Section 5.3. Pure tungsten, thoriated, ceriated, lanthanated and zirconiated tungsten are all listed in AWS A5.12. Oxide additions help emission characteristics and arc starting. Exam tip: remember GTAW = non-consumable tungsten; any process using a non-consumable electrode is either GTAW or PAW.

3Which GMAW metal transfer mode produces the lowest heat input and is preferred for thin sections and out-of-position welding?

A.Spray transfer

B.Globular transfer

C.Short-circuiting transfer

D.Pulsed spray transfer

Explanation: Short-circuiting transfer (GMAW-S) deposits metal only when the wire touches the pool, producing very low heat input and a small, easily controlled puddle. Per API RP 577 Section 5.4, this makes GMAW-S suitable for thin materials and all-position welding, although lack of fusion on heavy sections is a known risk. Exam tip: remember the transfer-mode heat-input order from lowest to highest - short-circuit, pulsed, globular, spray.

4Which statement about submerged arc welding (SAW) per API RP 577 is correct?

A.The arc is visible so the welder can observe the puddle directly

B.Flux shields the arc and molten pool from the atmosphere

C.SAW is primarily an out-of-position process for vertical welds

D.SAW cannot be used for carbon steel pressure vessels

Explanation: Per API RP 577 Section 5.6, SAW uses a bare solid or cored wire with a blanket of granular flux that melts to shield the molten pool and the buried arc from the atmosphere. Because the arc is under the flux, no visible arc or spatter is seen and high currents can be used. Exam tip: SAW is typically used for flat and horizontal welds on heavy sections - its high deposition rate is a main advantage.

5The acronym FCAW stands for which welding process?

A.Flux cored arc welding

B.Flash carbon arc welding

C.Forge cold-arc welding

D.Fused ceramic arc welding

Explanation: Flux cored arc welding uses a tubular electrode containing flux and sometimes alloying elements. Per API RP 577 Section 5.5, FCAW can be self-shielded (FCAW-S) or gas-shielded (FCAW-G). It combines the productivity of continuous wire feeding with the versatility of flux chemistry. Exam tip: memorize the full expansion of each acronym - simple terminology questions are common on API 577.

6Which current type and polarity is most commonly used for SMAW with E7018 electrodes?

A.DCEN (straight polarity)

B.DCEP (reverse polarity)

C.AC low frequency only

D.DC pulsed at 50 Hz

Explanation: E7018 low-hydrogen electrodes are designed to run on DCEP (direct current electrode positive, also called reverse polarity), which provides deeper penetration and a smoother arc. Some E7018 variants can also run AC. Per API RP 577 Section 5.2, electrode polarity is listed as an essential or nonessential variable depending on the process. Exam tip: the last digit of an SMAW electrode classification tells you coating type and usable current.

7Plasma arc welding (PAW) differs from GTAW primarily because PAW:

A.Uses a consumable electrode fed through the torch

B.Constricts the arc through a water-cooled copper orifice

C.Uses carbon dioxide as the shielding gas

D.Operates only on AC square-wave current

Explanation: Per API RP 577 Section 5.7, plasma arc welding is similar to GTAW but the tungsten electrode is recessed within a constricting copper nozzle that squeezes the arc through an orifice, producing a high-energy columnar plasma jet. This gives better arc stability, higher energy density, and keyhole welding capability. Exam tip: PAW is still a non-consumable-electrode process - do not confuse it with plasma cutting or GMAW.

8Which of the following is a primary advantage of GTAW over SMAW for root passes on stainless steel process piping?

A.Higher deposition rates

B.Greater tolerance to wind

C.Better control of heat input and weld quality

D.Elimination of the need for shielding gas

Explanation: GTAW gives the welder precise control of heat input, filler addition, and arc length, producing very clean welds ideal for stainless root passes where sensitization and chrome oxide formation must be minimized. Per API RP 577 Section 5.3, GTAW is the process of choice for high-purity and small-diameter root welds. Exam tip: in refinery piping, the root is GTAW and the fill/cap are often SMAW or FCAW.

9Which GMAW shielding gas mixture is typical for spray transfer on carbon steel?

A.100% CO2

B.75% argon / 25% CO2 or higher argon content

C.100% helium

D.80% nitrogen / 20% oxygen

Explanation: True axial spray transfer on carbon steel requires a shielding gas containing at least about 80% argon, commonly 75% argon / 25% CO2 or higher argon percentages. 100% CO2 produces globular-to-short-circuit transfer, not spray. Per API RP 577 Section 5.4 and Section 7, shielding gas composition is listed among the variables that affect transfer mode. Exam tip: remember that pure CO2 cannot support spray transfer.

10In SAW, the flux can be described by its behavior with respect to alloy pickup. A neutral flux is one that:

A.Adds significant silicon and manganese to the weld

B.Produces no significant change in weld metal composition across voltage changes

C.Removes all alloying elements from the weld metal

D.Can only be used with nickel-based alloys

Explanation: Per API RP 577 Section 7, a neutral flux produces no significant change in weld metal chemistry with moderate changes in arc voltage. Active fluxes add measurable amounts of silicon and manganese that vary with voltage, while alloy fluxes intentionally add alloying elements. Exam tip: remember active = Si/Mn varies with voltage, neutral = flat, alloy = intentional additions.

About the API 577 Exam

The API 577 Welding Inspection and Metallurgy certification is an Individual Certification Program (ICP) from the American Petroleum Institute for inspectors, welding engineers, and metallurgists working in refining and petrochemical facilities. The closed-book exam verifies a candidate's knowledge of welding processes (SMAW, GTAW, GMAW, FCAW, SAW), welding procedure specifications (WPS) and procedure qualification records (PQR) per ASME Section IX, welder performance qualification, nondestructive examination methods, weld discontinuities, metallurgy fundamentals, postweld heat treatment, and refinery/petrochemical welding issues. API 577 is widely recognized across the oil and gas industry and is often held alongside API 510, 570, or 653 fixed-equipment inspector certifications.

Questions

110 scored questions

Time Limit

3 hours 15 minutes

Passing Score

70% (set scaled score)

Exam Fee

$380 member / $440 non-member (American Petroleum Institute (Prometric))

API 577 Exam Content Outline

15%

Welding Processes

SMAW, GTAW, GMAW (spray/globular/short-circuit/pulsed), FCAW, SAW, PAW, and SW; process advantages, limitations, variables, and equipment per API RP 577 Section 5

20%

Welding Procedure and Welder Qualification

WPS and PQR preparation, essential/supplementary essential/nonessential variables, mechanical testing, and welder performance qualification per ASME Section IX Part QW and API RP 577 Sections 6-8

Welding Materials

Filler metals, electrode classification (AWS A5.x), SFA specifications, F-numbers, A-numbers, consumable storage and handling, and shielding gases per API RP 577 Section 7

14%

Metallurgy

Carbon/low-alloy and stainless steel metallurgy, phase transformations, HAZ, hardenability, hydrogen cracking, weldability, preheat and PWHT theory per API RP 577 Section 10

17%

Nondestructive Examination

VT, PT, MT, RT, UT (including PAUT/TOFD), ET and leak testing; acceptance criteria, discontinuity detection, and NDE limitations per API RP 577 Section 9

13%

Welding Inspection and Discontinuities

Inspector tasks before/during/after welding, weld discontinuity identification (cracks, porosity, slag, lack of fusion, undercut), and visual inspection per API RP 577 Section 4 and 9

Refinery and Petrochemical Welding Issues

Hot tapping, in-service welding, temper-bead and half-bead repair, creep-strength-enhanced ferritic (CSEF) steels, clad and dissimilar metal welds per API RP 577 Section 11

Terms, Definitions, Acronyms and Safety

API RP 577 Section 3 terminology and Section 13 safety precautions including arc radiation, fumes, hot work, and confined-space hazards

How to Pass the API 577 Exam

What You Need to Know

Passing score: 70% (set scaled score)
Exam length: 110 questions
Time limit: 3 hours 15 minutes
Exam fee: $380 member / $440 non-member

Keys to Passing

Complete 500+ practice questions
Score 80%+ consistently before scheduling
Focus on highest-weighted sections
Use our AI tutor for tough concepts

API 577 Study Tips from Top Performers

1Memorize the AWS A5.1 electrode designation cold: in E7018, the 70 = 70 ksi minimum tensile strength, 1 = all positions, 8 = low-hydrogen iron-powder covering with DCEP. API RP 577 Section 7 and Annex D cover the full AWS classification system and this appears on nearly every exam form

2Master ASME Section IX essential variables by process. For SMAW (QW-253) key essentials include P-Number change, F-Number change, A-Number change, t (deposited thickness), and preheat decrease of more than 100 degrees F. Know which variables are essential, supplementary essential, and nonessential for each process

3Learn the welder performance qualification thickness ranges in QW-452.1(b): a groove weld test coupon of 1/2 inch thick qualifies the welder for 1/8 inch through maximum to be welded. The 3/8 inch and above coupon qualifies unlimited thickness. These ranges are tested frequently

4Know preheat and PWHT requirements per API RP 577 Section 10.5 and 10.6. P-No. 1 carbon steels generally require 175 degrees F preheat above 1 inch thick or above 0.30% carbon equivalent. PWHT holding temperature for P-No. 1 is typically 1100-1200 degrees F at 1 hour per inch minimum

5Build an NDE comparison matrix: RT finds volumetric discontinuities through thickness but misses tight planar cracks; UT excels at planar flaws and thickness; MT only finds surface/near-surface discontinuities on ferromagnetic materials; PT finds only surface-breaking discontinuities on any nonporous material. API RP 577 Section 9 is heavily tested

Frequently Asked Questions

What score do I need to pass the API 577 exam?

API does not publish a fixed percentage but targets approximately 70% correct. The exam uses a set scaled-score passing standard established by the ICP committee to account for different exam forms. Candidates who pass simply see 'PASS' on their score report; those who fail receive a diagnostic breakdown by content area so they can target their restudy. The exam has 110 questions but only 100 are scored - the other 10 are unscored pretest questions sprinkled throughout.

Is the API 577 exam open-book or closed-book?

The API 577 exam is entirely closed-book. Unlike API 510, 570, and 653, which have an open-book section, nothing may be brought into the test center and no PDFs of standards are available on the computer. Every question must be answered from memory, so candidates must internalize the essential variables of ASME Section IX Part QW, the AWS electrode classification system, weld discontinuity definitions, and the NDE method table. This is a key reason API 577 feels harder than its short length suggests.

How hard is the API 577 exam?

API 577 is considered one of the more challenging ICP short-form exams because it is 100% closed-book yet spans two dense documents - API RP 577 3rd Edition and ASME Section IX Part QW. The toughest areas are WPS/PQR essential variables (QW-250 tables), welder qualification ranges (QW-452), and metallurgy topics such as hydrogen-induced cracking and PWHT requirements. Pass rates are not officially published, but prep providers estimate roughly 60-70% of first-time candidates pass.

Which reference publications are tested on API 577?

Per the official API 577 Body of Knowledge, questions are derived from two publications: API Recommended Practice 577, Welding Processes, Inspection, and Metallurgy, 3rd Edition (October 2020), and ASME Boiler and Pressure Vessel Code Section IX, Welding, Brazing, and Fusing Qualifications - Part QW only (Parts QB and QF are not tested). Candidates must own current editions and study them cover to cover. The Publications Effectivity Sheet for December 2025 through August 2027 exams confirms these editions.

What jobs can I get with API 577 certification?

API 577 is held by welding inspectors, QA/QC engineers, metallurgists, and fixed-equipment inspectors working at refineries, petrochemical plants, midstream facilities, and EPC contractors. It is commonly stacked with API 510 (pressure vessels), API 570 (piping), or API 653 (tanks) to qualify for senior inspection and turnaround roles. Salaries for API 577 holders typically range from $90,000 to $140,000 depending on experience and location, and offshore/international assignments often pay substantially more.

How should I prepare for the API 577 closed-book exam?

Read API RP 577 3rd Edition from cover to cover at least twice and make a condensed notes document for the essential variables tables in ASME Section IX (QW-252 through QW-265). Memorize AWS A5.1 electrode classification (for example E7018 = 70 ksi tensile, all positions, low-hydrogen iron-powder coating). Practice identifying weld discontinuities from descriptions, and build flashcards for NDE method strengths and limitations. Complete at least three full-length timed closed-book mock exams in the final two weeks of study.