2.1 Inspector Duties Across the Weld Lifecycle

2.1 Inspector Duties Across the Weld Lifecycle

Quick Answer: Under IAB-041 §3, the welding inspector’s role begins before welding, continues during the operation, continues after welding is complete, and is finalised only when results are properly reported. Inspection activities are defined in an Inspection and Test Plan (ITP). Before welding you confirm materials, approved WPS, qualified welders, and fit-up; during welding you witness and monitor procedure compliance; after welding you execute the inspection programme, select NDT or mechanical tests, and verify heat treatment.

IAB-041 (International Welding Inspection Personnel) frames the inspector not as a last-minute “look at the bead” role, but as a quality function that spans the entire fabrication cycle. If you only remember one sentence from this section for the Application of Standards oral and written papers, make it this: inspection starts before the arc is struck and ends only when the report is complete and traceable.

The Inspection and Test Plan (ITP)

As part of the quality system, inspection activities are defined in an inspection and test plan, which clearly describes what is required. The ITP is the project-level map that turns codes, client specifications, and drawings into scheduled actions: who inspects what, when, against which acceptance criteria, and whether the activity is a hold point (stop until released), witness point (notify so the inspector may attend), or a routine check.

In practice, the ITP links:

The inspector is frequently responsible for producing documents that ensure traceability of the components and related fabricating actions. The ITP tells you which documents must exist at each gate; your job is to confirm they exist, match the work, and support later reconstruction of “who welded what, with which procedure, on which heat of steel.”

Before Welding (Pre-Weld Assurance)

Prior to welding, the inspector must be assured that the materials are correct and that the shop has approved welding procedures and appropriately qualified welders. Written procedures and competent operators are essential to a quality welded product — but they are not enough if the joint is prepared badly or the wrong heat of plate is on the bench.

Pre-weld checks typically include:

1. Base metals — grade, thickness, heat/lot identification, certificate (e.g. EN 10204 type) matches the order and WPS essential variables; surface condition suitable (no excessive rust, oil, moisture, or damage).
2. Welding consumables — classification matches the WPS (for example ISO 2560 electrode designation for MMA); storage and handling (especially low-hydrogen electrodes) follow procedure.
3. Approved WPS / supporting qualification — a valid WPS (and supporting WPQR where required by the code or ISO 15614 route) covers the joint, process, position, thickness, and material group.
4. Welder / operator qualification — personnel hold current approval for process, position, and material range (e.g. ISO 9606 framework); identity can be linked to the work piece.
5. Fit-up and preparation — root gap, bevel angle, root face, alignment (high-low), cleanliness, tacks that do not introduce cracks or geometry that the WPS forbids.
6. Equipment and environment — power source, gas supply and purity for gas-shielded processes, wind/weather controls, preheat equipment ready if required.
7. Preheat (if specified) — minimum preheat achieved at the correct measurement location before the first pass.

Only when the inspector is satisfied that all is in order for welding to proceed does the role shift to witnessing and monitoring. Exam traps often offer “design a new WPS on the spot” or “change the joint geometry without engineering” as inspector duties — those belong to welding engineering / coordination, not to routine inspection verification.

During Welding (Witness and Monitor)

Once welding starts, IAB-041 highlights two basic interests:

1. Ensuring that the written procedures are being followed.
2. Checking for any physical signs of non-conformance that would affect the final product.

The inspector’s responsibilities include verifying base metals and consumables as they are used, observing fit-up where still visible, and watching the welding operation itself. In-process focus areas include:

• WPS parameters — current, voltage, travel speed (or heat input / arc energy where controlled), polarity, gas flow, stick-out, and bead sequence within qualified ranges.
• Consumable control — correct electrode or wire for root versus fill/cap; baking/holding of low-hydrogen consumables; no substitution without procedure control.
• Interpass temperature — both minimum (often tied to preheat) and any maximum limit that protects HAZ properties and toughness.
• Interpass cleaning and technique — slag removal, grinding if required, stringer versus weave limits, correct side of multi-sided joints.
• Heat treatment during fabrication — preheating and post-heating must follow an approved written procedure; the inspector must know enough about technique, equipment, and records to have confidence in the results.

In-process findings are valuable because they can stop a defective practice before hundreds of metres of weld are completed. A root run deposited outside the WPS heat-input window, or a preheat that was applied only at the start of the shift, is far cheaper to correct mid-joint than after final NDT and coating.

After Welding (Inspection Programme, NDT, Mechanical Tests, PWHT)

Once welding is completed, a new series of tasks begins. IAB-041 describes this phase as:

• Executing an inspection programme according to an approved procedure
• Maintaining the status of examination and testing
• Selecting specific welds for further NDT or mechanical testing

Typical post-weld duties include:

Heat treatment (preheating, post-heating, and post-weld heat treatment) can be a critical parameter. The inspector is often required to ensure it has been done properly. You are not expected to design the thermal cycle from first principles on the shop floor, but you must verify that the executed cycle matches the approved written procedure and that records support confidence in the result.

Typical Duties List (IAB-041 §3)

IAB-041 lists typical welding inspector duties (among others) as:

1. Interpretation of drawings and specifications
2. Verification of procedure (WPS) and welder or welding operator qualifications
3. Verification of the application of approved welding procedures
4. Selection of production test samples
5. Interpretation of test results
6. Preparation of reports and keeping of records
7. Preparation of inspection procedures
8. Check the correct application of NDT methods

Memorise this list as a closed set for exam questions that ask “which of the following is a typical inspector duty?” Anything that is pure production scheduling, pure commercial negotiation, or pure design engineering without an inspection link is usually outside the list. Conversely, if a task involves verifying compliance, selecting tests, interpreting results against criteria, or documenting status, it belongs in the inspector’s toolkit.

Lifecycle Thinking for the Exam

A reliable exam habit is to classify every duty into before / during / after / report:

• Before: materials, WPS, welder quals, fit-up, consumable storage, preheat readiness, ITP hold-point clearance.
• During: parameter monitoring, interpass temperature, technique, consumable identity, continued heat control.
• After: VT, NDT selection/extent check, production tests, PWHT verification, repair re-inspection.
• Report: collate observations into interim or final reports (covered in depth in the next section).

That classification also mirrors how real ITPs are written and how oral examiners often probe your thinking: they may describe a scenario and ask when you act and what document authorises the action. Your answer should always be anchored in the ITP, the WPS, and the applicable standard — not in personal preference.

Practical Scenario

A bridge fabricator is about to weld a full-penetration butt in ISO/TR 15608 group 1.2 steel, 25 mm thick, using MAG. Before the first arc, the IWI-S checks: plate certificates and heat numbers match the cut list; WPS MAG-25-G1 covers thickness and position; the welder’s ISO 9606 approval is current for the process and position; fit-up root gap and high-low are within WPS limits; G3Si1 wire and shielding gas match the WPS; preheat, if required by the WPS/code combination, is measured. During welding, the inspector spot-checks amperage, voltage, and travel speed, records interpass temperature, and confirms slag is cleaned between passes. After welding, VT is performed per ISO 17637 conditions, the ITP requires 10% UT on this joint class, and any PWHT (if specified for the assembly) is verified against the written procedure before final release. Every step is either a line on the ITP or a record supporting that line.

Master this lifecycle view and the eight typical duties. Later chapters on WPS/WPQR, ISO 5817, NDT methods, and QA documentation will fill in the technical detail; this section is about when you act and why the ITP is the defining document.