Section 9 Acceptance Standards for NDT – CWI Part C

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Section 9 Acceptance Standards for NDT – CWI Part C Practice Test

Prepare for the AWS CWI Part C Open Book Exam with this free practice test based on API 1104 Section 9: Acceptance Standards for NDT. This section is very important because it covers acceptance standards for imperfections detected by radiographic testing, magnetic particle testing, liquid penetrant testing, ultrasonic testing, and visual testing.

In this quiz, you can take a free practice test with the latest exam-style questions and answers for CWI Part C API 1104 Section 9 Acceptance Standards for NDT.

Take Free CWI Part C API 1104 Practice Test

This free quiz is designed for AWS CWI candidates, welding inspectors, QA/QC inspectors, NDT personnel, pipeline welding professionals, and students preparing for the AWS CWI Part C exam using API 1104.

Section 9 focuses on how weld imperfections are evaluated and accepted or rejected when found by NDT methods. It also explains the company’s right of rejection and the acceptance criteria for different types of discontinuities.

Quiz Details

Quiz Name: Section 9 Acceptance Standards for NDT – CWI Part C
Standard Covered: API 1104
Exam Type: AWS CWI Part C Practice Test
Total Questions: 10 Questions
Question Type: Multiple Choice Questions
Level: Exam Preparation Level

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What Is Covered in API 1104 Section 9?

API 1104 Section 9 provides acceptance standards for imperfections found by different NDT methods. These methods include radiographic testing, magnetic particle testing, liquid penetrant testing, ultrasonic testing, and visual testing.

This section is highly important for CWI Part C exam preparation because many questions may test your ability to identify discontinuity types, understand abbreviations, apply acceptance standards, and know when a weld may be rejected.

Main Topics Covered in Section 9

9.1 General

Section 9 presents acceptance standards for weld imperfections detected by NDT methods.

The main NDT methods covered include:

• Radiographic Testing – RT
• Magnetic Particle Testing – MT
• Liquid Penetrant Testing – PT
• Ultrasonic Testing – UT
• Visual Testing – VT

API 1104 also states that NDT shall not be used to select welds that are to be destructively tested for welder qualification.

Rights of Rejection

The company has the right to reject any weld even if the discontinuity appears to meet the acceptance limits in Section 9, when the company believes the depth of the discontinuity may be harmful to the weld.

This is important because many NDT acceptance standards are based mainly on discontinuity length. Some methods, other than ultrasonic testing, may not provide complete information about the depth of a discontinuity.

For this reason, the company retains final authority to reject welds when a discontinuity may be detrimental.

Radiographic Testing Acceptance Standards

Radiographic testing acceptance standards are covered in API 1104 Section 9.3.

This section defines and gives acceptance criteria for several radiographic discontinuities, including:

• Inadequate Penetration without High-Low – IP
• Inadequate Penetration due to High-Low – IPD
• Inadequate Cross Penetration – ICP
• Incomplete Fusion – IF
• Incomplete Fusion due to Cold Lap – IFD
• Internal Concavity – IC
• Burn-Through – BT
• Elongated Slag Inclusions – ESI
• Isolated Slag Inclusions – ISI
• Porosity
• Cluster Porosity – CP
• Hollow Bead Porosity – HB
• Cracks
• External Undercut – EU
• Internal Undercut – IU
• Accumulation of Imperfections

Candidates should pay close attention to these abbreviations because they are commonly used in API 1104 exam-style questions.

Inadequate Penetration and Incomplete Fusion

API 1104 identifies different types of penetration and fusion-related discontinuities.

Inadequate penetration without high-low is referred to as IP. Inadequate penetration due to high-low is referred to as IPD. Inadequate cross penetration, or ICP, can exist only in welds made from both the inside and outside of the pipe.

Incomplete fusion is also divided into two categories. Incomplete fusion open to the surface is referred to as IF. Incomplete fusion that is not open to the surface and is related to cold lap is referred to as IFD.

This distinction is important because API 1104 separates incomplete fusion into different categories for acceptance purposes.

Internal Concavity and Burn-Through

Internal concavity is referred to as IC. API 1104 permits internal concavity when the weld thickness is not less than the thinner of the two pipe wall thicknesses being joined.

When the minimum wall thickness is violated, the condition is evaluated as burn-through.

Burn-through is referred to as BT. API 1104 provides separate acceptance criteria for burn-through depending on whether the pipe outside diameter is 2.375 inches or greater or less than 2.375 inches.

Slag Inclusions

API 1104 separates slag inclusions into two main types:

• Elongated Slag Inclusions – ESI
• Isolated Slag Inclusions – ISI

Elongated slag inclusions are usually linear and may be located between the root bead and the hot pass. Isolated slag inclusions may have irregular shapes and may occur anywhere in the weld.

The acceptance criteria for slag inclusions depend on the pipe outside diameter and the type of slag indication.

Porosity

API 1104 provides acceptance criteria for different types of porosity.

Porosity may be evaluated as:

• Individual porosity
• Scattered porosity
• Cluster porosity
• Hollow bead porosity

Cluster porosity criteria apply to the final or cover pass. If cluster porosity occurs in other passes, it is evaluated under the criteria for individual or scattered porosity.

Cracks

Cracks are generally prohibited under API 1104 Section 9. However, shallow crater cracks or star cracks may be acceptable when they are 5/32 inch in length or less.

These shallow crater cracks are cracks at weld terminations caused by shrinkage. Although API 1104 permits this limited exception, proper welding technique should be used to prevent crater cracking.

Undercutting

Undercutting may occur on the outside or inside surface of the pipe.

API 1104 uses the following abbreviations:

• External Undercut – EU
• Internal Undercut – IU

Radiographic acceptance criteria provide limits for undercut length. When undercut is accessible for visual and mechanical measurement, API 1104 Section 9.7 and Table 4 are used for visual acceptance standards based on undercut depth.

Accumulation of Imperfections

In addition to meeting the acceptance criteria for each individual discontinuity, a weld must also meet the acceptance criteria for the total accumulation of imperfections.

The accumulated length of acceptable indications in a weld is limited by API 1104. This means a weld may contain several individually acceptable imperfections but still be rejected if their total accumulated length exceeds the permitted limit.

Base Metal Discontinuities

Base metal discontinuities discovered during radiographic testing, magnetic particle testing, liquid penetrant testing, or ultrasonic testing must be reported to the company for disposition.

This is important because discontinuities found near the weld may not always be weld defects, but they still require company review and decision.

Magnetic Particle Testing

API 1104 Section 9.4 covers magnetic particle testing acceptance standards.

Not every MT indication is caused by a weld imperfection. Some indications may be caused by magnetic or metallurgical variations and are considered irrelevant.

Indications with a maximum dimension of 1/16 inch or less are also considered nonrelevant unless proven otherwise.

Relevant indications are classified as:

• Linear indications, where the length is more than three times the width
• Rounded indications, where the length is three times the width or less

Linear indications are evaluated under MT acceptance criteria. Rounded indications are evaluated using porosity-related criteria.

Liquid Penetrant Testing

API 1104 Section 9.5 covers liquid penetrant testing acceptance standards.

The liquid penetrant testing requirements are the same as the magnetic particle testing requirements. Relevant and nonrelevant indications must be properly identified, and acceptable indications must meet the applicable acceptance criteria.

Ultrasonic Testing

API 1104 Section 9.6 covers ultrasonic testing acceptance standards.

UT indications are not automatically defects. The examiner must understand the difference between relevant indications caused by weld imperfections and nonrelevant indications caused by geometry, reinforcement profile, internal chamfering, or other shape-related conditions.

UT relevant indications may be classified as:

• Linear Surface – LS
• Linear Buried – LB
• Transverse – T
• Volumetric Cluster – VC
• Volumetric Individual – VI
• Volumetric Root – VR
• Accumulation of Relevant Indications

Understanding these UT indication categories is very important for CWI Part C exam preparation.

Visual Acceptance Standards for Undercutting

API 1104 Section 9.7 provides visual acceptance standards for undercutting when the undercut is accessible for visual and mechanical depth measurement.

These criteria supplement other VT acceptance criteria in the standard. They do not replace visual testing requirements found elsewhere in API 1104.

The permitted length of undercut depends on its depth. Shallow undercut may be permitted for longer lengths, while deeper undercut is more restricted.

What You Will Learn in This Quiz

This practice test will help you understand:

• Acceptance standards for NDT in API 1104
• Company rights of rejection
• Radiographic testing discontinuity abbreviations
• Difference between IP, IPD, ICP, IF, and IFD
• Internal concavity and burn-through criteria
• Slag inclusion categories
• Porosity categories
• Crack acceptance exception for shallow crater cracks
• External and internal undercut abbreviations
• Accumulation of imperfections
• MT and PT relevant indication rules
• UT indication classifications
• Base metal discontinuity reporting requirements
• Visual acceptance standards for undercutting

Why Practice Section 9 Acceptance Standards for NDT?

Section 9 is one of the most important sections for the AWS CWI Part C exam because it contains detailed acceptance criteria and many technical abbreviations.

Many candidates lose marks because they confuse discontinuity types, NDT methods, acceptance criteria, or abbreviation meanings. Practicing Section 9 questions helps improve code navigation, inspection judgment, and exam confidence.

Start the Free Practice Test

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Quiz – Section 9 Acceptance Standards for NDT – CWI Part C – 10 Questions
https://upweld.org/section-9-acceptance-standards-for-ndt/

Who Should Take This Practice Test?

This quiz is useful for:

• AWS CWI exam candidates
• CWI Part C API 1104 students
• Welding inspectors
• QA/QC inspectors
• NDT technicians
• Pipeline welding professionals
• Welding supervisors
• Welding engineers
• Students preparing for open-book code exams

Prepare Better for AWS CWI Part C

If you are preparing for the AWS CWI Part C exam, Section 9 Acceptance Standards for NDT is a must-practice topic. It explains the acceptance rules for weld imperfections found by RT, MT, PT, UT, and VT.

Take the free practice test now and improve your preparation for the AWS CWI Part C API 1104 exam.

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