Part B is the only hands-on part of the CWI exam. You work with plastic weld replicas, real gauges and a sample code you may never have opened before, all against the clock.
The good news: Part B rewards preparation. Here’s what AWS gives you on test day, how the materials fit together, and how to practice. We won’t share exam questions or answers. AWS treats exam content as confidential, and so do we.
Part B at a Glance
| Detail | CWI Part B Practical |
|---|---|
| Format | Hands-on activities plus a written, paper-based test |
| Questions | 46, mostly multiple choice |
| Time | 120 minutes, with no scheduled breaks |
| Where | AWS exam sites (see the exam schedule at aws.org) |
| Book type | Open book, using AWS’s Book of Specifications (provided) |
| Passing score | 72% |
| Order | You take Part B before Parts A and C |
AWS runs Part B in up to three group sessions a day: check-in around 7:00 a.m., 10:45 a.m. or 2:45 p.m. The doors close at the end of check-in, and late arrivals aren’t admitted. Plan to arrive 30–45 minutes early. For eligibility, application deadlines and fees, see our CWI requirements guide.
What the questions cover
AWS publishes the minimum share of Part B questions in each area:
- Welding inspection and flaws: 34%
- Procedure and welder qualifications: 28%
- Mechanical tests and properties: 8%
- NDE: 8%
- Use of specifications and drawings: 8%
Plan your study time to match.
The Four Things on Your Table
AWS supplies all of the following to every candidate on exam day.
1. The Book of Specifications (BOS)
The BOS is a sample code written just for the exam. For U.S. and Canadian exams, AWS currently lists the 2017 BOS in U.S. customary units. It’s a free PDF download from the AWS CWI page, and that’s the single best study tool you have.
AWS’s foreword is blunt: the BOS looks like a real codebook, but it isn’t one. Some clauses resemble codes you know, so read carefully and don’t answer from memory. That’s the trap that catches experienced welders and inspectors.
The BOS is organized into:
- Clause 1: General requirements
- Clauses 2–4: Workmanship and visual acceptance criteria for three applications: structural steel, pipeline and pressure piping
- Clause 5: Procedure qualification (WPS and PQR)
- Clause 6: Performance (welder) qualification
- Annexes I–X: A-number and F-number tables, base metal and M-number tables, bend specimen preparation, formulas and conversions, pipe schedules, blank WPS/PQR/WQTR forms, and industry terms
Many questions require you to combine a clause with a table, a figure note or an annex. AWS’s own sample question on bend specimens points to the notes on the Annex IV figures.
2. The Book of Exhibits
The Exhibits booklet is a set of sample welding documents and photos: things like WPSs, PQRs, WQTRs, heat treat charts and pictures of NDE methods. A question might say “examine Exhibit EEB-16” and ask what’s being shown or whether a document meets the BOS.
You can’t see the real Book of Exhibits before the exam. AWS keeps it confidential, so don’t buy anything sold as “the actual exhibits.” Prepare by reading real procedure and qualification documents and checking them against the BOS.
3. The Weld Replica Set
You get a four-piece plastic replica set: a T-joint, a groove weld, bend specimens and a pipe specimen. You’ll measure and visually inspect them and decide if they’re acceptable under the BOS.
Because they’re plastic, AWS tells you to ignore pinholes, seams, glue squeeze-out and color differences that come from the molding process. Focus on the weld features the question asks about. The exam replicas are confidential, so practice replicas from training providers are look-alikes, not copies.
4. The Inspection Tool Kit
AWS lists these tools in the kit:
- Fillet weld gauges
- V-WAC gauge
- Dial caliper
- Ruler
- C4.1 gauge
- Protractor
- Hi-lo gauge
- Magnifying glass, mirror and flashlight
The BOS says you’re expected to use every instrument in the kit, including zeroing it where that applies. AWS sells a sample tool kit for practice.
What you can bring
Bring a valid government-issued ID, No. 2 pencils, and an acceptable calculator (four-function, construction, or non-programmable scientific). Phones, notes, scratch pads, food and drinks, and bulky hoodies aren’t allowed in the room. Personal items, bags included, can’t come in either, so plan ahead for where you’ll leave yours.
How to Practice for Part B
- Download the BOS and read the foreword first. Then read the table of contents until you can say from memory which clause covers structural, pipeline and pressure piping.
- Map the tables and annexes. Make a one-page index of where each table, figure and annex lives. You can’t write in the exam BOS, so the goal is to know the book, not to mark it up.
- Practice “clause plus table” lookups. Take a weld feature (say, undercut on a pipeline weld) and trace every place in the BOS that applies to it, including notes.
- Work through real paperwork. Use the blank WPS, PQR and WQTR forms in the annexes. Fill them in from a procedure you know, then check them against Clauses 5 and 6 to see what would make a record unacceptable.
- Get hands-on time with gauges. Practice zeroing the dial caliper and reading the fillet gauge, V-WAC and hi-lo gauge until it feels automatic. Measure real welds in your shop, not just pictures.
- Practice on the clock. 46 questions in 120 minutes works out to about 2.5 minutes each, and some questions take longer because you have to measure. Do timed sets and flag time-eaters to come back to.
- Read every answer choice in full, and transfer answers carefully to the answer sheet.
How Our Part B Course Helps
Lone Star CWI is a registered AWS Educational Institute. Our CWI Prep – Part B Practical course (about 30 hours, $399.99) follows the structure of the BOS:
- Clause-by-clause lessons, flashcards and quizzes for Clauses 1–6 and the annexes, including application quizzes
- A lesson on essential variables, plus a section on reading PWHT charts
- Lessons on the fillet weld gauge, V-WAC, hi-lo gauge, dial caliper, machinist ruler and protractor
- Timed mock exams modeled on the Part B format and built from a question bank, including a version with replica images
- Practice weld replicas and tools available to buy, so you can train with your hands, not just your eyes
The course content is our own. Our mock exams are modeled on the Part B format; they don’t reproduce AWS’s confidential exam material.
Taking Part C on API 1104 later? Read Do You Need to Buy API 1104 for the CWI Exam? Studying from home? See how our online CWI training works anywhere in the U.S.
Frequently Asked Questions
How many questions are on the CWI Part B exam?
There are 46 questions, and you have 120 minutes to answer them.
Is the CWI Part B exam open book?
Yes. AWS provides the Book of Specifications at the exam. It’s also a free PDF on the AWS website, so you can study from it ahead of time.
Can I see the Book of Exhibits before the exam?
No. AWS keeps the Exhibits booklet and the replica set confidential. Prepare by practicing with real WPS, PQR and WQTR documents and the BOS.
What tools are used on CWI Part B?
Fillet weld gauges, a V-WAC gauge, dial caliper, ruler, C4.1 gauge, protractor, hi-lo gauge, magnifier, mirror and flashlight. AWS provides all of them.
Can I bring my own gauges or a copy of the BOS to Part B?
No. AWS supplies every exam material. You bring your ID, No. 2 pencils and an approved calculator.
Where can I take Part B?
Part B is given at AWS exam sites. Check the exam schedule at aws.org for upcoming dates and site codes.
Part B is where hands-on practice pays off. Start our Part B Practical course, save with the Full CWI Bundle, or contact us with questions.