Welding Procedure Sample: A Complete Guide to WPS, PQR, and Qualification

A single miswritten welding procedure can shut down a multi-million dollar fabrication project. Whether you’re a contractor facing code compliance or a welder trying to understand documentation, knowing how to read and prepare a proper welding procedure sample can mean the difference between approval and costly rework.

Introduction to Welding Procedure Samples

In fabrication, the weld takes minutes; the paperwork takes days. Picture a pressure vessel shop that finishes a full assembly, only to have the inspector halt sign-off because nobody can produce the welding procedure sample that governed the work. The welds may be metallurgically perfect, yet the job stalls until the documentation catches up. That gap between “we welded it right” and “we can prove we welded it right” is exactly what a welding procedure sample exists to close.

In practice, a welding procedure sample is a documented example of a Welding Procedure Specification (WPS) — a written, code-ready recipe that tells a welder exactly how a joint must be made. It covers the welding process, base metals, filler metal, joint geometry, preheat, heat input ranges, positions, and the inspection requirements that follow. Shops use samples as templates: start with a proven document, fill in the variables that match your actual job, and submit it for review before the arc is struck.

Why Fabricators Rely on Procedure Samples

A WPS is not bureaucracy for its own sake. Major construction and fabrication codes make qualified welding procedures a condition of doing the work. AWS D1.1, the structural welding code for steel, requires a written procedure for most production welds. ASME Section IX governs procedure and welder qualification for pressure-retaining components, and API 1104 covers pipeline welds. The logic is identical in each case: if you cannot document how the weld was made, you cannot demonstrate that it meets the standard. The American Welding Society publishes these standards, ASME Section IX defines qualification rules for pressure equipment, and API 1104 addresses pipeline welding.

Documentation also ties directly to weld quality and liability. When a weld fails in service, one of the first questions an investigator asks is whether the work followed a qualified procedure. A properly written and qualified WPS shows that joint design, heat input, filler selection, and preheat were chosen for the material combination — not guessed at on the shop floor. It also protects the contractor: following a qualified procedure is a documented defense against claims of negligence.

What a Good Sample Tells You

Reading a sample WPS carefully reveals how all the pieces of welding documentation fit together. The specification is backed by a Procedure Qualification Record (PQR) that proves the procedure works, and by welder qualification records that prove the individuals can execute it. These documents are covered in detail in the next section, but the sample already shows the structure: essential variables stated plainly, ranges given rather than single numbers, and references to the code clause that permits each choice.

A useful sample also demonstrates scope. A structural steel WPS for a bridge connection behaves very differently from a procedure for an aluminum hull, a stainless pipe spool, or a heat exchanger repair. Aluminum work, for instance, demands tight control of cleaning and oxide removal before the arc ever starts — the kind of detail captured in guides like Aluminum Cleaner for Welding: How to Prep Aluminum Right. Choosing the wrong sample for the wrong application is one of the most common causes of rejected paperwork.

Who Uses Welding Procedure Samples

Three groups interact with these documents daily:

• Contractors and welding engineers write or adapt WPSs, qualify them with test coupons, and keep the records current.
• Inspectors verify that the procedure on the floor matches the approved document, that essential variables stay within range, and that supporting records exist.
• Welders work to the WPS — reading parameters, checking preheat, and flagging anything in the field that falls outside the written limits.

Each role sees a different side of the same document, which is why clarity matters. A WPS written in vague language invites misinterpretation; a WPS written precisely becomes a shared reference that reduces rework, disputes, and inspection hold points.

Occupational safety rules reinforce this discipline. Employers must maintain welding-related safety practices under OSHA’s General Industry standards, and fume exposure controls are informed by NIOSH research on occupational hazards. A WPS primarily governs weld quality, but it sits inside a wider compliance system that touches ventilation, hot-work permits, and fire prevention.

The Cost of Skipping Proper Documentation

The consequences of working without a qualified procedure range from inconvenient to expensive. Projects get rejected at inspection. Welds require removal and replacement. In the worst case, a failed joint leads to injury, environmental release, or litigation where the absence of a WPS becomes the central exhibit. Accreditation bodies and owners increasingly evaluate fabricators on traceability and documentation practices aligned with standardized quality frameworks, such as those from NIST.

The good news is that the system is learnable. A welding procedure sample is essentially a map: it shows what a compliant document looks like, which variables the code cares about, and how technical choices translate into written limits. Once you can read one confidently, you can tell whether a proposed procedure is defensible before it ever reaches an inspector’s desk.

The following sections build on this foundation, starting with the three-document relationship — WPS, PQR, and welder performance qualification — that makes the whole qualification system work.

Understanding WPS, PQR, and WPQ: Key Differences

If you have ever stood in a fabrication shop while an inspector flipped through a binder and asked for “the qualification,” you already know how quickly paperwork can stall production. The three documents at the center of that conversation are the WPS, the PQR, and the WPQ. They sound almost identical and get used loosely on the shop floor, but they do completely different jobs. Confusing them is one of the fastest ways to get a weld rejected.

The simplest way to hold them apart: the WPS tells the welder what to do, the PQR proves that what the WPS says actually works, and the WPQ proves that a particular welder can follow that WPS and produce sound welds. Most construction, pressure vessel, and piping codes require all three before production welding begins.

The WPS: Your Instruction Sheet

A Welding Procedure Specification is a written set of directions, the document the welder actually reads at the machine. A complete WPS identifies the welding process, the base metal group and thickness range, the filler metal classification, the shielding gas, joint design, preheat and interpass temperature, electrical characteristics such as polarity and current range, and the positions the procedure is qualified for.

Codes divide WPS support into two routes. A prequalified WPS sits inside the code itself: AWS D1.1, for example, publishes joint details and recommended parameter ranges a shop can adopt without running a single test, provided it stays inside the listed limits. Everything else needs procedure qualification, which means test coupons, testing, and a PQR. There is no third option, and there is no such thing as a WPS qualified by a welder’s experience alone.

The PQR: The Proof Behind the WPS

A Procedure Qualification Record is the evidence file. It documents that someone welded a test coupon using the proposed parameters, that the coupon was then subjected to destructive and mechanical testing, and that the results met code acceptance criteria. Typical testing includes a visual examination, a guided bend test, and a tensile test; impact toughness testing is added when the service temperature demands it.

Under ASME Section IX, those test results are recorded on a PQR form that the manufacturer and, when required, the authorized inspector sign. The AWS standards catalog covers the parallel process in the D1.1 structural series, while API 1104 qualifies procedures for pipeline construction with its own weld test requirements. Different codes, same logic: nobody writes a WPS on theory alone.

The recipe analogy holds. The WPS is the recipe; the PQR is the taste test that says the recipe works. Once the PQR exists, you can write as many WPS documents as you like that stay inside its qualified ranges.

The WPQ: Qualifying the Person

A Welder Performance Qualification, sometimes called a welder qualification or continuity record, tests the operator rather than the procedure. A welder welds a test coupon using a specific WPS, the coupon is cut and tested, and a pass earns a stamp or certificate covering particular processes, positions, and material groups. Supervisors and welding engineers also carry separate performance qualifications, because approving work is a different skill from laying a bead.

Certificates do not last forever. Most codes require continuity, meaning the welder must have used the process within a defined window, commonly six months, or face retesting. Let that lapse and the certificate means nothing, however many good welds are on file.

How the Three Documents Fit Together

Document	Answers the question	Tested by	Valid for
WPS	How do we weld this?	Supported by a PQR or prequalified by code	Until variables change
PQR	Does the procedure work?	Coupon plus destructive/mechanical testing	Until essential variables change
WPQ	Can this person weld it?	Welder test coupon and visual/radiographic checks	Subject to continuity rules

The chain always runs in the same direction: test the procedure first, produce the PQR, write the WPS from the PQR’s ranges, then qualify each welder who will use it. Whether you are welding structural steel or running all-position roots on pipe, that order never changes. The same logic applies to repair work governed by a written procedure, such as an aluminum boat welding procedure.

It also explains why a shop might hold a dozen WPS documents but only a handful of PQRs. WPS pages are cheap to write once a PQR exists. The expensive part, the part that gets re-welded and re-tested, is earning that first qualification.

Why the Chain Breaks Down

Most compliance failures happen at the joints between these documents. A WPS cites a PQR that covers 3/8-inch plate but the job calls for 1-inch material. A welder’s certificate expired four months ago and nobody checked. A revision was made to the WPS without recognizing that the change altered an essential variable, voiding the qualification.

Codes in the United States ultimately exist to protect people at work, which is why welding documentation sits alongside general industry requirements such as those in OSHA’s 1910 standards. Documentation is not bureaucratic theater; it is the traceable record that the joint you cannot see inside a pressure vessel or a structural column was made by a qualified welder, under a qualified procedure, to a code-accepted standard.

In the next sections we will look at which codes apply where, and then break down exactly what has to appear on a welding procedure sample for it to survive review.

Governing Codes and Standards for Welding Procedures

A fabricator wins a contract to build a steel pedestrian bridge. The welders are skilled, the equipment is solid, the fit-up is clean. Then the third-party inspector asks for the qualified welding procedure before witnessing a single pass. The shop foreman hands over a WPS written eight years ago for a different job, covering a different steel grade and a different electrode classification. No production welding happens that day, and the schedule slips by a week.

The lesson is simple: welding procedures do not exist in a vacuum. A specific code or standard requires them, and that code dictates what the procedure must contain, how it gets qualified, and who can approve it. If you do not know which code governs your work, you cannot write a procedure sample that will pass review.

Why Welding Is a “Code-Driven” Trade

Most trades run on drawings, specifications, and good judgment. Welding is different. A weld is often a permanent, load-bearing, or pressure-containing connection that cannot be visually verified from the inside, so the industry built formal systems to prove that a given combination of process, filler, and technique will produce a sound joint.

Those systems are codified. A code tells you what tests a welding procedure must pass, which variables you can change without requalifying, and what records you must keep. Standards bodies such as the American Welding Society and ASME publish these documents and update them on regular cycles. Ignoring them is not a paperwork shortcut; it is a liability that can void an inspection or fail a hydrostatic test.

AWS D1.1: Structural Steel Welding

If your work involves buildings, bridges, or structural steel frames, AWS D1.1, Structural Welding Code—Steel, is almost certainly the governing document. It is one of the most widely used welding codes in North America, covering fabrication and erection of carbon and low-alloy steel structures.

Under D1.1, a welding procedure must be qualified before production use, and the code allows two paths: a prequalified WPS or a qualified-by-testing WPS. Prequalified procedures are a genuine time-saver because they rely on decades of proven practice rather than fresh testing, but they carry strict limits on base metal thickness, joint geometry, process, filler classification, and position. Step outside those limits and the WPS must be qualified by testing. D1.1 also governs welder qualification, inspection acceptance criteria, and the essential variables that trigger requalification, and it is frequently invoked alongside project-specific requirements from owners and engineers.

ASME Section IX: Pressure Vessels and Piping

When the weld holds pressure, the rules change. ASME Boiler and Pressure Vessel Code, Section IX, governs qualification of welding and brazing procedures for pressure vessels, boilers, and pressure piping. The official scope is published on the ASME Section IX page.

Section IX is distinctive because it focuses almost entirely on qualification mechanics rather than fabrication rules. It defines the essential, supplementary essential, and nonessential variables for each process and lays out exactly which changes require a new Procedure Qualification Record. Design, inspection, and acceptance requirements live elsewhere, in Section VIII for pressure vessels or B31.3 for process piping.

That division matters when you prepare a procedure sample. A Section IX-qualified WPS will not by itself satisfy a pressure vessel project; it must be paired with the construction code governing that vessel’s design and inspection. Think of Section IX as the grammar and the construction code as the content.

Code / Standard	Primary Scope	Who Uses It
AWS D1.1	Structural steel buildings and bridges	Structural fabricators, ironworkers, bridge contractors
ASME Section IX	Welding/brazing qualification for pressure equipment	Pressure vessel and piping fabricators, boiler makers
API 1104	Pipeline and related facilities welding	Pipeline contractors, transmission and distribution crews
AWS D1.6	Structural stainless steel	Stainless structural fabricators
AWS D1.2	Structural aluminum	Aluminum structural fabricators

API 1104: Pipeline Welding Procedures

The oil and gas industry relies on API 1104, Welding of Pipelines and Related Facilities, which covers transmission pipelines, distribution systems, and associated facilities, including procedure qualification, welder qualification, and acceptance standards for girth welds. Current editions are maintained by the American Petroleum Institute and are listed on the API 1104 standards page.

Because pipeline girth welds are frequently made in the field, in challenging positions and harsh conditions, the qualification process emphasizes root pass integrity, penetration, and defect acceptance. Welders must be tested on the actual pipe diameter, wall thickness, and position they will weld in production. This is one area where a generic procedure borrowed from a structural job will not survive scrutiny.

Other Codes and Standards You May Encounter

• AWS D1.2 governs structural aluminum, which behaves very differently from steel. Reviewing dedicated guidance such as aluminum MIG welding and aluminum flux welding helps you see how process variables affect qualification.
• AWS D1.6 covers structural stainless steel, where sensitization and distortion control drive many procedural decisions.
• ASME B31.1 and B31.3 govern power piping and process piping respectively, and both call on Section IX for qualification.
• AWS D17.1 applies to aerospace fusion welding, an area with extremely tight process control. For context, see aerospace welding standards.
• OSHA regulations reference qualified welding procedures in certain applications, particularly where worker safety and structural integrity overlap. Relevant general industry requirements appear in 29 CFR 1910.

You may also encounter owner specifications, military standards such as MIL-STD-248, and international equivalents like ISO 15614, which mirror the qualification logic of the American codes. If you export work or serve multinational clients, procedures may need qualification to more than one standard.

Matching the Code to the Application

The practical takeaway: identify the governing code first, then build the procedure sample around that code’s requirements. A structural contractor reaches for D1.1, a pressure vessel shop works from Section IX plus the construction section, and a pipeline crew follows API 1104. Trying to use one procedure across all three is a recipe for rejected documentation and failed inspections. Once you know which rulebook applies, the next question is what a compliant procedure actually contains.

Essential Elements of a Welding Procedure Sample

A welding procedure sample is only as reliable as its details. Without items like a root opening, interpass temperature limit, or a clearly specified filler metal, an inspector has nothing to verify against the qualification record. For this reason, codes such as AWS D1.1 and ASME Section IX require each WPS to cover a fixed set of elements.

How Codes Classify Variables

Not every change carries the same consequence. ASME Section IX sorts variables into essential, supplementary, and nonessential categories. An essential variable, if changed outside of its qualified range, invalidates the procedure and forces requalification. Supplementary variables must be written into the WPS and controlled in production, but altering them does not automatically invalidate the PQR. Nonessential variables are voluntary items of good practice. AWS D1.1 uses a similar logic, with the added option of a prequalified WPS, which only applies when strictly within code-permitted ranges and requires no supporting PQR.

Base Metals and Surface Condition

Every WPS must identify the base metal by a recognized classification, not a shop nickname. ASME uses P-Numbers and Group Numbers, while AWS D1.1 uses the same P-Number system for structural steels. From there, the qualified thickness range, and pipe diameter range when applicable, must be stated. Surface condition is just as critical. Contaminants like oil, oxide, paint, or mill scale can affect the weld pool. For aluminum, proper chemical cleaning is required, as outlined in Aluminum Cleaner for Welding: How to Prep Aluminum Right.

Filler Metals and Consumables

The WPS must specify the filler metal by its AWS classification (such as E7018 or ER70S-6), along with its A-Number, F-Number, diameter range, and manufacturer specification or code-approved equivalent. For low-hydrogen consumables, storage and reconditioning requirements are mandatory. This includes oven use, holding quivers, and exposure time limits. The logic behind choosing these electrodes is covered in Alloy Steel Welding Electrodes: Selection, Use & Safety.

Joint Design, Groove Details, and Backing

For groove welds, the joint geometry must be fully shown, including the bevel angle, root face, root opening, and gap tolerance. Backing details are equally required, whether it’s a steel backing strip, consumable insert, ceramic backing, or no backing at all. Stating “no backing” is a specification in itself. The number of passes, any difference between root and fill passes, and required back-gouge, grind, or backing weld sequences must also be included.

Preheat and Interpass Temperature

Preheat and interpass limits control cooling rate and hydrogen mobility in the heat-affected zone, making them essential variables for most codes. The WPS must state the minimum preheat temperature, the measurement method (contact thermometer, thermal crayon, or pyrometer), the distance to maintain it from the joint, and the maximum interpass temperature. Going below preheat or above the interpass limit can lead to cracking or softening, even if the weld appears sound.

Process, Position, and Technique

The welding process (SMAW, GMAW, FCAW, GTAW, SAW, or a combination) must be listed alongside qualified positions, such as flat, horizontal, vertical, overhead, or pipe equivalents 1G through 6G. Technique details like stringer beads versus weaving, maximum weave width, travel direction, and cleaning between passes are also required. Since position is often an essential variable, qualification in flat does not extend to overhead. The selection of consumables for all positions is further explained in All Position Welding Rod Guide: Types, Uses & Tips.

Electrical Characteristics, Heat Input, and Shielding Gas

Amperage, voltage, polarity, and travel speed determine heat input. The WPS must list qualified ranges for each, as they directly impact fusion and the heat-affected zone:

Heat input (kJ/in) = (60 × Amps × Volts) ÷ (1000 × Travel speed in in/min)

For gas-shielded processes, the gas or mixture, its permitted tolerance, flow rate, nozzle details, and any purge requirements must be stated. For example, 75% argon / 25% CO₂ is common for steel GMAW, while aluminum typically uses 100% argon, as detailed in Aluminum MIG Welding: The Complete Practical Guide. Substituting gas blends can be an essential change. Working with a trusted supplier, such as Airgas Welding Supplies, helps maintain consistent gas quality.

Element	What the WPS must state
Base metal	P-Number/Group or AWS grade, qualified thickness range
Filler metal	AWS classification, F-Number, diameter, manufacturer spec
Joint design	Bevel angle, root face, root opening, backing type (or none)
Preheat/interpass	Minimum preheat, measurement method, maximum interpass
Process and position	Process type, qualified positions, technique
Electrical characteristics	Amps, volts, polarity, travel speed ranges
Shielding gas	Composition, tolerance, flow rate, nozzle details, purge if required

All of these ranges come directly from the supporting PQR. Keeping them accurate and consistent is what turns a form into a usable, enforceable welding procedure.

Procedure Qualification: From Sample to Approved PQR

A welding procedure sample on paper is only a proposal. To be valid, it must be proven with physical evidence that the settings you recorded can produce sound welds for your materials, thicknesses, and joint type. This process is called procedure qualification, and its result is the Procedure Qualification Record, or PQR.

Think of it this way: the WPS is the recipe, the test coupon is the dish, and the PQR is the lab report proving the dish meets the required standards. Without a PQR, the WPS carries no weight in front of an inspector.

Step 1: Weld the Test Coupon Exactly as Written

The most common mistake in qualification is deviating from the proposed procedure while welding the test coupon. Every detail must be followed exactly as listed, from the welding process and filler metal, to shielding gas, preheat, interpass temperature, and heat input range. If you adjust settings to “help” the test, you’re only proving those altered conditions work.

• Match your materials: Use coupon material that matches the production grade and falls within the thickness range you’re qualifying.
• Cover all positions: A flat coupon only qualifies flat welds. If your work includes vertical or overhead joints, those positions must be tested. You can learn more about these applications in our All Position Welding Rod Guide.
• Record your filler: Any filler metal, such as an Alloy Steel Welding Electrodes product, must be listed by its exact classification on the procedure being qualified.
• Plan for range: Multiple coupons may be needed to qualify a wider range of thicknesses, diameters, or material groups.

Step 2: Examine Before You Cut

Before sectioning the coupon, most codes require nondestructive examination. This typically includes a full visual inspection, with radiographic or ultrasonic testing when specified. This step is critical, as cutting the coupon destroys any chance to detect internal discontinuities across the full weld length. If any flaws are found at this stage, the coupon must be rejected before destructive testing begins.

Step 3: Destructive and Mechanical Testing

Next, the coupon is sectioned into specimens and put through mechanical testing. The tests required will depend on the governing code, but most qualifications include the following:

Test	What it proves	Typical acceptance focus
Transverse tension	Load-carrying strength	Must meet or exceed the base metal’s specified minimum tensile strength
Guided root and face bends	Ductility and surface soundness	No open discontinuities exceeding the code’s allowed size
Side bends	Full-thickness soundness	Examined on the bent convex face for internal flaws
Toughness (Charpy V-notch)	Fracture resistance	Minimum absorbed energy at the specified service temperature

While tension and bend tests make up the majority of qualifications, toughness testing is required when service temperatures are low or variables fall outside previously qualified impact data. Governing documents such as ASME Section IX, AWS standards, and API 1104 all outline the exact specimen preparation and acceptance limits for these tests.

Step 4: Judge Every Result Against the Code

There is no gray area when evaluating test results. All specimens must meet the code’s acceptance criteria with no exceptions. A single failed bend or out-of-range tensile test invalidates the coupon, requiring a completely new qualification to the same proposed procedure.

Step 5: Record, Sign, and Issue the PQR

Once all results pass, they must be recorded onto the PQR with complete traceability. This includes base metal specs and coupon thickness, filler metal classification, welding process, essential variables, shielding gas, positions, preheat and interpass temperatures, heat treatment, all test results with measured values, the test date, and the testing laboratory. Most importantly, the PQR must be signed and dated by the qualified personnel required by the code. From there, it becomes the supporting evidence for the WPS, unlocking the code-assigned ranges that allow one qualification to cover multiple procedure sheets.

Common Mistakes When Creating Welding Procedure Samples

A welding procedure sample can look complete on paper and still fail inspection, and the failures happen in predictable ways. They rarely come from invented numbers. They come from borrowed documents, a line or two changed, and no check that the change pushed the procedure outside its qualification. Knowing the traps first saves rework, delay, and field repair.

Changing Essential Variables Without Requalification

This is the single most common compliance failure, and it usually starts with a well-intentioned shortcut. Essential variables are the parameters a code identifies as directly affecting weld quality: preheat, interpass temperature, heat input, filler classification, current and polarity, transfer mode, joint position, and thickness range. Under ASME Section IX, any change outside the range recorded on the Procedure Qualification Record invalidates the WPS resting on it. AWS D1.1 draws the same line with its own essential and supplementary essential variables.

The classic shop-floor version: a procedure was qualified using short-circuit GMAW transfer, but the welder switches to spray transfer because it runs faster and looks cleaner. Nothing on the WPS permits it, so every weld laid that way came from an unapproved procedure and is rejectable. The same happens when heat input creeps past a documented maximum or preheat is skipped because the plate “wasn’t that cold.” The procedure did not change by itself. Someone changed it and kept welding.

Incomplete Shielding and Backing Documentation

Another frequent failure is listing the shielding gas as “argon/CO2 mix” with no ratio, no flow rate, and no mention of backing conditions. On carbon steel that looks cosmetic; on aluminum and stainless it decides whether the weld survives service. Oxygen reaching the back of a root pass on stainless promotes sugaring and kills corrosion resistance, which is why purging, flow rates, and backing dam details belong in the procedure. Aluminum work is even less forgiving about gas purity, flow, and torch setup, as covered in Aluminum MIG Welding: The Complete Practical Guide.

Backing needs the same attention: permanent strip or none, ceramic or steel, open root or backed, and the resulting penetration classification all affect what the procedure actually qualifies. Leave those details vague and an inspector cannot confirm the procedure matches the joint being welded.

Using Non-Standard or Homemade Forms

Codes specify required content rather than a mandated layout, which tempts shops to build their own forms. The trouble starts when a homemade form omits required information: the PQR reference number, the essential variable table, qualified ranges for thickness, diameter and position, preheat and interpass temperatures, or the filler AWS classification. A common scenario is copying a supplier’s prequalified WPS, swapping in a different alloy, and submitting it as if it were qualified. A mill certificate is not a PQR, and a supplier data sheet is not a procedure qualification record. Without test records tied by reference number, the procedure will be rejected however tidy the form looks.

Base Metal Group Mismatch

Qualification does not automatically transfer between materials. Both AWS D1.1 and ASME Section IX group base metals, and qualification extends only to similar metals within the same group. Qualifying on ASTM A36 and assuming it covers every carbon steel on the job is a common error, as is qualifying on 316L stainless and applying the procedure to Alloy 20, which sits in a different grouping with its own filler and heat control demands, as explained in Alloy 20 Welding: Procedures, Filler Metals, and Best Practices. An alloy steel welding electrode substituted for a qualified filler of another classification creates the same problem. Verify the base metal group, filler group, and qualified thickness range before the sample reaches production.

Overreaching on Position and Range

Position is a qualified variable, so flat-position qualification does not cover vertical and overhead work. An electrode marketed as all-position capable does not make the procedure all-position qualified; product capability and procedure qualification are separate questions, a distinction we unpack in All Position Welding Rod Guide: Types, Uses & Tips. The same overreach applies to thickness and diameter: welding 3/4-inch plate with a procedure qualified through 1/2 inch, or running a 10-inch pipe root with a procedure capped at 8 inches, puts you outside the qualified envelope.

Catch these errors on the desk and they cost a phone call. Catch them after the welds are in and they cost cutting out, requalifying, and a deviation to explain to the owner’s inspector. OSHA’s general industry standards expect welding work to follow recognized safe practices, and codes treat an unqualified procedure the same way: the weld is only as good as the paperwork behind it. Review the sample against the governing code’s variable list, confirm the qualification chain, and keep every parameter written down where the next person can find it.

Practical Applications and Industry Examples

A welding procedure sample looks very different depending on what you are building. The variables that matter for a structural steel beam have almost nothing in common with those that govern a pressure vessel shell or a live pipeline repair. Four application areas show how a sample is shaped by the governing code, the service conditions, and the environment where the welding actually happens.

Structural Steel Fabrication

Most structural fabrication in the United States follows AWS D1.1, the Structural Welding Code for steel. A typical structural procedure sample here covers SMAW, FCAW-S, or GMAW on plate and structural shapes in common grades like ASTM A36 and A572 Grade 50.

What makes structural procedures distinctive is the focus on joint details and positions. A shop procedure for a girder flange-to-web connection specifies the exact joint geometry, the notch condition, and whether the weld is a complete joint penetration (CJP) or partial joint penetration (PJP) weld. CJP groove welds on statically loaded members still require qualification, and for cyclically loaded structures AWS D1.1 imposes much tighter controls on fit-up, backing, and reinforcement removal.

Application	Governing Code	Key Variables in the Sample
Structural steel	AWS D1.1	Joint type, position, electrode classification, preheat
Pressure vessels	ASME Section VIII with Section IX	PWHT, impact testing, weld metal composition
Pipeline	API 1104	Field weld positions, pipe schedule, girth welds
Repair work	Owner specification or AWS D1.1 Clause 4	Existing base metal, service history, weldability

Preheat is another structural staple. D1.1 Table 5.8 sets minimum preheat and interpass temperatures based on base metal thickness and welding process, and those numbers must appear in the procedure sample. For anyone selecting electrodes for these applications, our guide to alloy steel welding electrodes covers how classification and toughness ratings tie back to code requirements.

Pressure Vessel Work

Pressure vessel fabrication is where procedure documentation gets strictest. Welding qualification falls under ASME Section IX, which uses a rule-based system of essential, supplementary essential, and non-essential variables. Change an essential variable after qualification and the procedure is no longer valid; requalification is required.

Consider a sample for a SA-516 Grade 70 pressure vessel shell. It specifies the P-Number grouping, the filler metal F-Number and A-Number, the welding position, preheat, interpass temperature, and whether post-weld heat treatment is applied. Critically, if the vessel service involves low-temperature impact requirements, the sample must call out impact testing and the qualification coupon has to be tested at the specified temperature. Heat input limits then creep in as supplementary essential variables.

Pipeline and Field Welding

Pipeline construction and repair typically follows API 1104, which covers welding of pipelines and related facilities. The sample for a girth weld has to account for fixed pipe positions, where the welder progresses through flat, vertical, and overhead zones in a single joint.

Repairs add another layer. A repair procedure must address the condition of the in-service base metal, possible contamination, removal of cracked material (often by carbon arc gouging, as we explain in our air arc welding and carbon arc gouging guide), and whether the line can be purged or must be welded hot-tap style. Qualification for these situations sometimes requires test welds on production pipe of the same grade, wall thickness, and coating condition as the actual repair.

Field welds need procedures adapted for site conditions a shop never faces: wind, moisture, limited access, position, and inconsistent power. A shop WPS that works perfectly indoors may be unusable on a windy bridge deck, which is why contractors maintain separate field samples with adapted shielding gas arrangements, wind screens, or a switch to flux-cored or stick processes that tolerate the environment. The same adaptation logic applies in marine settings, where our AJ Marine welding guide discusses process and corrosion choices for hull and deck work.

Repair and Specialty Applications

Repair welding is often the hardest category to document because you are welding to an unknown or previously welded base metal. AWS D1.1 Clause 4 allows welding to base metals that cannot be identified, provided the welder and procedure are qualified for the material’s presumed category. For pressure equipment, repairs frequently fall under the owner’s or jurisdiction’s requirements rather than a generic code clause.

Specialty repairs bring their own challenges. Aluminum wheel repair demands careful control of heat input and cleaning, which our alloy wheel welding guide details. Aluminum boat work adds corrosion and hull distortion concerns covered in aluminum boat welding. Even cleaning chemistry is a procedure variable in practice, since residual contaminants sabotage weld quality; see aluminum cleaner for welding for the prep side of that equation.

Whatever the application, the principle holds: the sample must reflect the real conditions of production. Safety requirements from OSHA’s General Industry standards and fume exposure guidance from NIOSH belong in the supporting documentation, not as an afterthought.

Modifications, Revisions, and Maintaining Compliance

A qualified welding procedure is never a “set it and forget it” document. Fabrication scopes shift, engineers approve new filler metals, clients change a material spec, and codes issue addenda. How you handle those changes determines whether your WPS stays valid or quietly becomes a compliance liability. This section covers the revision process, the triggers that force requalification, and the record-keeping discipline that keeps audits painless.

When a Change Is Just an Edit, and When It Triggers Requalification

Not every change carries equal weight. Codes classify variables into three buckets:

• Essential variables — changes that affect weld soundness or mechanical properties. Altering these on a qualified WPS invalidates it and requires requalification with a new test coupon.
• Supplementary essential variables — these apply only when impact testing is required. Under AWS D1.1, a change beyond the permitted range of a supplementary essential variable requires requalification only when CVN testing is part of qualification. Without an impact test requirement, the same change may need nothing more than a paperwork update.
• Non-essential variables — usually editable by the welder or supervisor within the WPS, such as changing electrode manufacturer or trade name within the same classification.

This distinction trips up a lot of shops. A supervisor swaps to a different brand of 7018 rod, sees the same AWS classification, and assumes nothing needs to happen. That is correct. The same supervisor bumps preheat by 50°F on a quenched-and-tempered alloy steel joint and edits the WPS in place, and the procedure is suddenly out of qualification. Reviewing Alloy Steel Welding Electrodes: Selection, Use & Safety is a useful reminder of how sensitive alloy systems are to thermal history, which is exactly why codes guard preheat and interpass temperature so tightly.

Revision Control Done Properly

A WPS without revision tracking is a trap. The fabricator on the floor may be welding to Rev 0 while the engineer of record approved Rev 2. Proper revision control includes:

• A unique revision number or letter in the WPS header, incremented on every issued change.
• An effective date and the name or signature of the approver.
• A short description of change — “Revised preheat range per EOR directive” is useful; “updated” is not.
• A cross-reference showing whether the change required a supporting PQR update.

Superseded revisions should be stamped obsolete and removed from the point of use, not left loose in a welder’s folder. If the revision changes an essential variable, the new WPS cannot be released until a matching PQR exists.

Understanding Your Range of Qualification

Every PQR supports a defined envelope: thickness range, consumable diameter range, position range, and process-specific ranges. A single qualification test on 3/8-inch plate may cover quarter-inch through unlimited thickness under AWS D1.1 rules, but that same test does not automatically cover 6G pipe positions or a different process. Before reusing a procedure on a new job, confirm the joint falls entirely inside the qualified ranges. Ranges are the most common reason a “technically qualified” procedure fails an audit — the WPS exists, it just does not cover that weld.

Position is a frequent surprise. A flat-position qualification says nothing about overhead work, which is why many shops separate structural plate procedures from pipe procedures. Shop guidance like the All Position Welding Rod Guide helps welders understand which consumables are even capable of running out of position before qualification is considered.

Record Keeping Requirements

Most codes require that qualification records be retained and available for inspection. In practice, that means maintaining the WPS, the supporting PQR, welder performance records, and any test reports as a linked package. Under OSHA’s General Industry standards, employers must document that welding, cutting, and brazing operations are performed safely and in accordance with recognized practices, and project owners frequently add contractual retention periods of seven years or more.

API 1104 goes further in pipeline work: when a contractor holds an approved procedure, the company may periodically review it to confirm the contractor is following the approved conditions. The API 1104 standard page publishes current addenda that can change qualification and requalification rules, so verify your edition annually.

Strategies for Staying Compliant Over Time

1. Schedule an annual WPS review. Compare each active procedure against the latest code edition, current filler classifications, and active project specifications.
2. Track code addenda. AWS D1.1, ASME Section IX, and API 1104 all receive revisions; the AWS standards and publications listing is the fastest way to see what changed.
3. Assign ownership. One named person should hold approval authority for procedure revisions.
4. Audit the floor, not just the binder. Confirm welders are actually using current parameters — an approved WPS that is ignored in practice still fails inspection.
5. Flag consumable changes early. Substituting electrodes, as covered in the alloy steel electrode selection guide, is non-essential only within the same classification.

Shops that pass audits without drama treat procedures as living documents with a clear chain of custody: every change numbered, dated, approved, and tied back to a PQR. That discipline costs a few hours a year and saves far more in rework and rejected welds.

Practical Tips for Using Welding Procedure Samples Effectively

While having a well-written welding procedure sample can save a massive amount of time, it is not something that can be blindly copied over to a new job. Each fabrication project comes with its own set of materials, conditions, and code requirements. With that being said, utilizing these samples effectively comes down to a proactive approach from contractors, inspectors, and welders alike. Here are some of the most impactful tips to ensure code-compliant implementation from start to finish.

For Contractors: Selecting and Customizing the Right Sample

As the driving force behind a project, contractors hold the responsibility of approving all documentation before any arc is struck. When selecting a sample to build from, there are a few key things to keep in mind:

• Verify your governing code first: Before utilizing any procedure, always verify the governing code for your scope of work. Different industries abide by different standards such as AWS D1.1 for structural steel, ASME Section IX for pressure vessels and piping, or API 1104 for pipeline work. Choosing a sample written to the wrong code is one of the quickest ways to receive a rejection.
• Match your application and materials: A sample must be qualified for your specific application and materials. For example, the parameters utilized for aluminum boat welding will drastically differ from those needed for structural carbon steel. This same principle applies to more niche jobs such as alloy wheel welding or alloy 20 welding due to their unique metallurgical properties.
• Don’t be afraid to consult the experts: Work with qualified welding engineers or code experts when needed. Certain projects, such as those seen in aerospace welding, have very tight tolerances. Having a professional review your customization prevents major non-conformance issues down the road.
• Account for your environment: Factors such as ambient temperature, field repairs, and joint accessibility can all require changes. Be sure to factor in these conditions when adjusting preheat, interpass temperatures, or travel speeds to fit your jobsite.

For Inspectors: Verifying Before, During, and After

Inspectors are the gatekeepers to compliance. When reviewing a procedure sample for approval, it’s crucial to be meticulous to uphold both quality and safety standards set forth by organizations such as OSHA and NFPA.

• Trace every variable: Ensure that the ranges listed on the WPS can be backed by its PQR. Pay extra attention to essential variables, as any change outside of qualified ranges will require requalification.
• Check material traceability: Verify that the base metals and filler metals listed on the procedure match what is being issued to the shop or field. This becomes increasingly important when working with dissimilar metals or exotic alloys.
• Validate safety considerations: Cross check that the procedure aligns with proper ventilation and PPE recommendations from NIOSH. This is especially crucial for processes that produce higher fume levels, like those taught in an aluminium welding course.
• Document revisions: Any approved changes to a procedure must be logged. Never allow an outdated hard copy of a WPS to be utilized on the production floor.

For Welders: Training and Proper Implementation

The most qualified procedure in the world means nothing without proper execution. For this reason, ensure welders are trained to the specific WPS they will use prior to starting production. This training should not be assumed, but practiced.

Training Focus	Practical Tip
Parameters	Practice with the exact amperage, voltage, and travel speed ranges listed prior to passing a test plate.
Equipment	Familiarize yourself with the machines being used. Different setups for aluminum MIG welding or aluminum flux welding can drastically affect arc behavior.
Joint Prep	Utilize the proper cleaning methods, such as those found with an aluminum cleaner for welding, to prevent porosity.
Safety	Adhere to all safety protocols and reference guidance from NIST and your company’s safety program for your process.

Most importantly, if a variable ever falls outside of the qualified range, welders must stop and notify their supervisor or inspector immediately. No in-the-moment adjustments that violate the WPS should ever be made.

Final Implementation Checklist

Before production begins, utilize this final checklist to solidify compliance:

• Qualified backing: Is the procedure backed by a valid, unexpired PQR that matches your code of construction?
• Welder qualification: Have all assigned welders passed their WPQ to the specific WPS, process, and position being utilized?
• Review consumables: Are the filler metals, shielding gases, and storage methods in alignment with what is specified?
• Verify calibration: Have all welding and measuring equipment been calibrated to the requirements of your quality program?

By implementing these tips, you can confidently take any welding procedure sample and transform it into an approved, safe, and productive welding practice for your specific job. This proactive mindset not only prevents rework, but most importantly, preserves the integrity of every weld that leaves your shop or jobsite.

Conclusion and Key Takeaways

A welding procedure sample only has value if it can be proven. For the welder, it’s a working guide. For the quality manager, it’s a required record. For the inspector, it’s proof that production matches a qualified test. These three perspectives must all align, and they can only do so when the procedure is backed by qualification under the correct code. Standards such as AWS D1.1 from the American Welding Society, ASME Boiler and Pressure Vessel Code Section IX, and API 1104 for pipeline welds all make this requirement clear. Qualification isn’t a formality, it’s proof that a set of parameters will produce sound welds for the materials and joint being used.

The Documentation Chain

Every compliant welding program relies on three interdependent records. Each one serves its own purpose, and none can replace the others:

• WPS (Welding Procedure Specification) – The instruction used in production, covering the process, base metal group, filler classification, positions, preheat, interpass temperature, heat input limits, and post-weld heat treatment.
• PQR (Procedure Qualification Record) – The test evidence that supports the WPS. It documents the coupon weld, all destructive and nondestructive test results, and every essential variable recorded during qualification.
• WPQ (Welder Performance Qualification) – The record proving a specific welder can produce sound welds using a qualified procedure, within its defined scope.

If any link is missing, the chain is broken. A qualified welder on an unqualified procedure, or a qualified procedure with an unqualified welder, is noncompliant. This also goes beyond code compliance. Structural, pressure, and pipeline welds carry weight in more ways than one, and qualified procedures help limit welding fume exposure by enforcing correct consumables, ventilation, and preheat methods. Oversight for welding in general industry falls under OSHA’s General Industry standards (29 CFR 1910), with exposure concerns tracked by NIOSH.

Essential Variables: Know When Requalification Is Required

The most practical way to avoid costly rework is to understand essential variables. Each code defines them, but the rule stays the same: changing an essential variable outside of its allowed range invalidates the qualification. Shifting processes, changing filler metal classifications, exceeding qualified thickness ranges, or dropping below the minimum preheat are all common examples. Checking these limits before making a change takes minutes, while requalifying a coupon can take days and come with significant lab costs. Some changes can be handled with an authorized WPS revision, but others require full requalification with no exceptions.

Implementation Takes a Team

No procedure stays correct without coordination. Welding coordinators and engineers select the code and authorize revisions. Welders follow the instructions in production and flag issues when written requirements aren’t practical for real conditions. Inspectors verify that the WPS in use is current, qualified, and applicable to the joint in front of them. When these roles work as a team rather than in silos, issues are caught before production welds are made. This mindset applies across all materials as well. For scopes involving nonferrous work, the same qualification discipline is critical, as shown in Aluminum MIG Welding: The Complete Practical Guide and Aerospace TIG Welding: Standards, Techniques, and Training.

Key Takeaways to Act On

1. Match to the code: Confirm the governing standard for your job, whether it’s structural, pressure, pipeline, or repair work.
2. Never split the WPS and PQR: The procedure is only valid with its supporting qualification record.
3. Qualify the welder: Procedure qualification and welder performance qualification are separate and both must be met.
4. Respect essential variables: Know them for your code to avoid unnecessary and avoidable requalification.
5. Revise deliberately: All changes must be authorized, traceable, and supported by records for the retention period required by your code.
6. Communicate: Keep engineers, welders, and inspectors aligned throughout the job.

In the end, the paperwork isn’t separate from good welding. It’s what makes skilled craftsmanship trustworthy, verifiable, and ready to stand behind for years to come.

Frequently Asked Questions

What is a welding procedure sample?

A welding procedure sample is a template or example document of a Welding Procedure Specification (WPS) that shows the required format and elements. However, it only becomes valid for use when properly qualified through a Procedure Qualification Record (PQR) per the applicable code.

What is the difference between WPS and PQR?

A WPS is a set of instructions telling the welder how to make the weld, including parameters and techniques. A PQR is the record of the actual test weld made to qualify that procedure, documenting the results of destructive testing and proving the procedure is sound.

Do I need a welding procedure for every job?

Not necessarily. Requirements depend on the governing code, project specifications, and application. Structural, pressure vessel, and pipeline work often require qualified procedures, while some minor repairs may have different requirements based on code jurisdiction.

When does a welding procedure need requalification?

Requalification is typically required when essential variables are changed beyond the ranges allowed by the code. Examples include changing base metal to a different group, significant changes in filler metal, or changes to preheat requirements depending on the governing standard.

Can I use a sample WPS from another company?

Generally no, unless it has been properly qualified for your specific materials, joint design, and application under the governing code. Even if the format is similar, the qualification is project and company specific in most cases.

Which code applies to my welding procedure?

The governing code depends on your application. AWS D1.1 is common for structural steel, ASME Section IX for pressure equipment, API 1104 for pipelines, and other codes may apply based on jurisdiction, contract requirements, or industry.

Who can qualify a welding procedure?

Qualification must be performed per code requirements, typically under the supervision of qualified personnel. Test coupons are welded and tested by qualified labs or under the direction of a Certified Welding Inspector or qualified welding engineer as specified by the governing code.

What tests are required for procedure qualification?

Required tests vary by code and thickness, but commonly include tensile tests, bend tests, and visual inspection. Some applications require impact testing or other specialized tests based on service conditions and code requirements.