CWS (ABWM) common mistakes
CWS · Understand the traps and how to avoid them.
Answering that a welder's qualification test (performance test) qualifies the welding procedure, or that a WPS is the document that qualifies the welder.
The three documents (WPS, PQR, welder performance qualification) are all studied together, so candidates collapse them into one idea and pick whichever term appears in the stem.
What to do instead
Memorize the one-line chain and re-derive it before answering: PQR = test record that qualifies the procedure; WPS = written instructions derived from the qualified PQR; performance qualification = record that a specific welder can deposit sound weld to a qualified WPS. When a stem asks 'what qualifies X', name the document, not the activity.
Treating a change in process, shielding gas, filler classification, position, or base-metal thickness as a minor WPS edit, when it is actually an essential or supplemental essential variable.
Candidates read the revision as paperwork and reason from practical shop experience ('we do it all the time') rather than from the variable table in the code.
What to do instead
Build a short recall sheet of essential variables for each common process (SMAW, GMAW/FCAW, SAW) and for each one ask: does this change affect mechanical properties or soundness? If yes, it is essential and requires requalification unless the code explicitly permits a supported range. Nonessential variables (e.g., joint detail, travel direction) require only a WPS revision.
Misreading filler-metal and electrode classification digits, e.g., reading E7018 as '70,000 psi tensile with 1 = coating type' or confusing ER70S-6 with E70T-1.
The digit strings look similar across systems, and candidates memorize the number as a whole label instead of decoding position by position.
What to do instead
Decode in a fixed order every time: prefix (E = electrode, ER = rod, E70T = tubular), first two digits = minimum tensile strength in ksi, next digit = usable position, last digit(s) = coating/current type or, for S/T designators, chemistry and shielding. Say the decode out loud in the order you write it.
Applying AWS D1.1 structural acceptance limits (undercut, porosity, weld size tolerances) to a D1.3 sheet-steel job or to a statically loaded member when the stem specifies cyclic loading.
D1.1 is the most drilled code, so it becomes the default answer whenever a limit is asked, and the load category in the stem gets skimmed.
What to do instead
Read the stem first for three things: the code/thickness, the loading category (static vs cyclic), and whether the limit applies to visual or NDT acceptance. State those three aloud, then select the number. For cyclically loaded joints, remember the limits tighten (e.g., undercut and weld profile become more restrictive) and do not import a static limit.
Choosing the wrong NDT method for the intended flaw, e.g., specifying PT to find subsurface lack of fusion, MT on austenitic stainless steel, or RT to find a lamination in the base metal.
Candidates remember method names and typical pictures but not the physical principle (surface-only vs volumetric, magnetic vs non-magnetic, thickness limits).
What to do instead
Reduce each method to two attributes before answering: what depth it reaches (surface / near-surface / volumetric) and what material or geometry limits it (ferromagnetic only for MT, density/thickness and radiation safety for RT, surface-breaking only for PT). Match the flaw location in the stem to the depth attribute first, then check the material restriction.
Reading a welding symbol by its arrow side only, or misreading where the tail/reference information and the size, length, and spacing designators belong.
The symbol is treated as a picture rather than a grammar, so candidates answer from the shape they recognize rather than from which side of the reference line the element sits.
What to do instead
Walk the symbol in a fixed sequence: reference line, arrow side vs other side, process/reference in the tail, then the element's size, length, pitch, and contour. If the stem gives an interpretation rather than a symbol, sketch the two candidate symbols on scratch paper and compare them to the description in the stem.
Failing cost-per-unit-length or deposition-rate arithmetic, e.g., forgetting the 60-minute conversion in heat input (J/in = volts x amps x 60 / travel speed in ipm) or comparing processes on deposition rate without converting to deposited pounds per hour and then to cost per foot.
The formulas are known in shape but applied with mixed units (ipm vs in/min of deposit, lb/hr vs g/min), and the exam offers the answers produced by the typical unit slip.
What to do instead
Write the units next to every number before computing, and cancel them explicitly. Keep one card with the three workhorses: heat input (V x A x 60 / travel speed), deposition rate (wire feed speed x cross-section x density, with units converted), and cost per foot (filler + gas + labor hours x burdened rate, all divided by feet deposited). Check the answer's magnitude: a wrong power of 60 is the most common giveaway.
Selecting the PPE answer for a fume, ventilation, or confined-space question instead of the engineering/administrative control the stem is testing, or assigning the hazard abatement to the welder rather than to the supervisory chain.
PPE is the most familiar control and the easiest to picture, so it wins over ventilation, substitution, or permit procedures that the question was actually about.
What to do instead
Apply the control hierarchy in order before answering: eliminate/substitute, engineer (ventilation, extraction, positioner), administrate (permit, rotation, training), then PPE last. On supervisory items, the correct answer is the one that names who verifies the control and how it is documented, not who wears the equipment.
Letting a welder continue on production because a qualification certificate is on file, without checking that the process, position, thickness range, and continuity (recent production welding with that process) are still valid.
The certificate is treated as a permanent credential, so the supervisor answers from the existence of paperwork rather than from its scope and currency.
What to do instead
Before answering any 'may this welder do this work' item, check four things in this order: process and filler, position and progression, thickness/pipe-diameter range, and continuity of use within the code's stated interval. If any one is outside the record, the answer is requalification, not proceed.
On 'what should the supervisor do first' items, choosing the diplomatic or reporting answer (notify the customer, hold a meeting, revise the drawing) instead of stopping and containing the nonconforming work.
Candidates optimize for workplace harmony or pick the most 'senior-sounding' action, and the exam offers escalation answers that look professional but skip containment.
What to do instead
Use a fixed priority ladder for supervisory action items: stop and segregate the nonconforming work, mark and document it, determine disposition with the responsible authority, initiate corrective action, then communicate. Eliminate any option that lets the work progress or that starts with paperwork before the physical containment is in place.