AWS D1.1:2025 · Quick Reference Card

AWS D1.1:2025 Quick Reference

Q: What does AWS D1.1:2025 cover?

AWS D1.1:2025 Structural Welding Code — Steel covers the design, fabrication, and inspection requirements for welded structural steel construction. It applies to carbon and low-alloy steels with a minimum specified yield strength up to 100 ksi (690 MPa) and base metal thickness 1/8 inch (3 mm) or greater. The code is referenced by AISC 360 Specification for Structural Steel Buildings and by most state DOT bridge specifications for non-fracture-critical work. The code covers SMAW (stick), GMAW (MIG), FCAW (flux core), SAW (submerged arc), GTAW (TIG), and ESW/EGW (electroslag/electrogas) processes. It does not cover sheet steel under 1/8 inch (governed by D1.3), stainless steel (D1.6), aluminum (D1.2), reinforcing bar (D1.4), bridges with cyclic loading or fracture-critical members (D1.5), or tubular structures (Clause 9 of D1.1 with cross-references to D1.1 main body). The 11 clauses are organized by lifecycle: scope, normative references, terms, design (Clauses 4 and 9), prequalification (5), qualification (6), fabrication (7), inspection (8), and three specialty clauses (9 tubular, 10 strengthening/repair, 11 stud welding).

Q: What is the difference between Clause 5 and Clause 6 in D1.1?

Clause 5 of AWS D1.1:2025 covers prequalified Welding Procedure Specifications — joint configurations, materials, and parameters that the code accepts as qualified by reference, eliminating the need for procedure qualification testing. Clause 5 includes prequalified joint details (Figures 5.1 through 5.10), prequalified base metal groups (Table 5.6), prequalified filler metal classifications (Table 5.7), preheat requirements (Table 5.11), and essential variables for prequalified WPSs (Table 5.5). Clause 6 covers procedure qualification testing — when prequalification is not applicable (non-prequalified joint, non-prequalified material, or essential variable outside prequalified ranges), the contractor must perform a Procedure Qualification Record (PQR) per Clause 6.2.1 to qualify a WPS. Clause 6 includes test specimen requirements (Figures 6.1 through 6.18), WPS qualification test specimen requirements (Tables 6.2 through 6.5), and the essential variables that govern PQR scope (Tables 6.6 through 6.10 by process). The practical rule: if you can build to Clause 5 with prequalified WPS, do so — it eliminates testing cost. If your joint or material falls outside prequalification, you need a PQR per Clause 6.

Q: What is AWS D1.1 Table 5.11?

AWS D1.1:2025 Table 5.11 specifies minimum preheat and interpass temperatures for prequalified WPSs. The table is organized by Table 5.11 preheat category/process rows, welding process group, and base metal thickness range. Each row gives the minimum preheat in degrees Fahrenheit and Celsius. For example, Category B steel (most common A36, A572 Gr 50) welded with low-hydrogen process at thickness over 3/4 inch through 1-1/2 inch requires 50°F (10°C) minimum preheat. Footnotes A through E define exceptions including minimum preheat for restraint conditions, the relationship between preheat and interpass temperature (per Clause 7.6.5, minimum interpass equals minimum preheat), and the exception for bridges where supplementary requirements may apply. Per AWS D1.1:2025 §5.11, preheat is required for all welding when the values in Table 5.11 are above ambient temperature. Failure to maintain minimum preheat is the single most common cause of underbead cracking in carbon steel welds. Use the Clause5 preheat calculator at /welding/preheat-calculator/ for instant per-steel lookups.

Q: What is AWS D1.1 Table 7.7?

AWS D1.1:2025 Table 7.7 specifies minimum fillet weld sizes based on base metal thickness. The table has four rows: T less than or equal to 1/4 inch requires 1/8 inch minimum fillet leg; T greater than 1/4 inch and less than or equal to 1/2 inch requires 3/16 inch minimum; T greater than 1/2 inch and less than or equal to 3/4 inch requires 1/4 inch minimum; T greater than 3/4 inch requires 5/16 inch minimum. Per Footnote A, T equals the thicker part joined for non-low-hydrogen processes without preheat (single-pass required), but T equals the thinner part joined for low-hydrogen processes and non-low-hydrogen with cracking prevention per Clause 6.8.4. Per Footnote B, the minimum fillet size need not exceed the thinner part thickness. Per Footnote C, 3/16 inch [5 mm] is the minimum for cyclically loaded structures; it raises the first-row 1/8 inch value and does not cap thicker-material rows. These minimums exist to prevent underbead cracking caused by insufficient heat input into thick base metal — too small a fillet on thick plate cools too quickly, locking in residual stresses and hydrogen. For edges 1/4 inch or thicker, the maximum fillet size is material thickness minus 1/16 inch per Clause 4.5.2.9.

Q: What is AWS D1.1 Table 8.1?

AWS D1.1:2025 Table 8.1 specifies visual inspection acceptance criteria for fillet welds, complete joint penetration (CJP) groove welds, and partial joint penetration (PJP) groove welds, separated by statically loaded vs cyclically loaded structures. The table covers crack acceptance (cracks of any size are unacceptable for both static and cyclic), weld profile (acceptable convex profile per Figures 8.4 through 8.6), undersize tolerance (5% of weld length may be undersize per the diminished-thickness rule), undercut (1/32 inch maximum for static, 1/100 inch for cyclic per direction-of-stress rules), porosity (1/32 inch maximum diameter for individual pores, with frequency limits), and fusion (complete fusion required, no incomplete fusion at root or sidewall). Per AWS D1.1:2025 §8.9, all visual inspection shall be performed by personnel meeting the qualification requirements of Clause 8.1.4 — typically a Certified Welding Inspector (CWI) per AWS QC1 or an equivalent inspector qualification. Visual inspection is performed before any volumetric NDT (UT or RT) per Clause 8.13.

Q: What are the base metal groups in AWS D1.1?

AWS D1.1:2025 Table 5.6 lists approved prequalified base metals in Groups I through V by specification, grade, thickness limits, yield strength, and tensile range. Groups I through V include approved steels such as A36, A53 Gr B, A500 Gr B/C, A572 Gr 50/60/65, A588, A709 HPS70W, A913 Gr 60/65/70/80, A992, and A1066. Table 5.7 selects matching filler metals by base-metal group. Table 5.11 then sets preheat by its own process/category/thickness rows, so the practical lookup path is: identify the Table 5.6 group, choose a Table 5.7 filler metal, then apply Table 5.11 preheat.

Q: What is the difference between prequalified and qualified WPS?

A prequalified WPS per AWS D1.1:2025 Clause 5 uses a joint configuration, base metal, filler metal, and welding parameters that the code accepts as qualified by reference. The contractor writes the WPS document but does not perform qualification testing — the code's body of historical test data substitutes for project-specific qualification. To use a prequalified WPS, all of the following must hold: joint matches Figures 5.1 through 5.10, base metal is in Table 5.6, filler metal matches Table 5.7 for the base metal group, preheat meets Table 5.11, and all essential variables stay within Table 5.5 ranges. A qualified WPS per Clause 6 is required when any of the prequalified conditions cannot be met. The contractor must perform a Procedure Qualification Record (PQR) — weld a test coupon to the proposed parameters, then perform qualification testing per Tables 6.2 through 6.5, as applicable to the joint type. The PQR validates the specific parameter combination and the resulting WPS is qualified for production use within the essential variable ranges of Tables 6.6 through 6.10. Prequalified is faster and cheaper; qualified is more flexible.

Q: What welding processes does AWS D1.1 cover?

AWS D1.1:2025 covers six welding processes: Shielded Metal Arc Welding (SMAW, stick), Gas Metal Arc Welding (GMAW, MIG), Flux-Cored Arc Welding (FCAW, both gas-shielded FCAW-G and self-shielded FCAW-S), Submerged Arc Welding (SAW), Gas Tungsten Arc Welding (GTAW, TIG), and Electroslag and Electrogas Welding (ESW/EGW). Each process has its own essential variables in Tables 5.5 (prequalified) and 6.6 through 6.10 (qualified). SMAW and GMAW are the most common in structural fabrication. FCAW is dominant for in-position welding on heavy structural members. SAW is used for shop production of long welds (girders, beams). GTAW is used for root passes on critical CJP welds and for stainless overlay. ESW/EGW are specialty processes for very thick sections — note that ESW requires a project-specific qualification per §6.2.4 because of its high heat input characteristics. Note: Stud welding is covered separately in Clause 11. Resistance welding is not covered by D1.1; use AWS C1.1 for resistance spot welding of steel.

Q: Where do I find essential variables for D1.1 WPS?

Essential variables for AWS D1.1:2025 prequalified WPSs are in Table 5.5, organized by welding process. For example, SMAW has essential variables including electrode classification (A5.1 or A5.5), electrode diameter (which determines amperage range), polarity (DCEP for low-hydrogen E70xx series), preheat (Table 5.11), interpass temperature (≥ minimum preheat per §7.6.5), travel speed (within prequalified ranges by joint type), and welding position. Essential variables for qualified WPSs are in Tables 6.6 (SMAW), 6.7 (SAW), 6.8 (GMAW/FCAW), 6.9 (GTAW), and 6.10 (ESW/EGW). The qualified-WPS essential variables are stricter and define the range over which a single PQR qualifies a WPS — for example, base metal thickness range qualified by a single PQR is the test coupon thickness ±25% (most processes, see Tables 6.6 through 6.10). Changes to essential variables require either re-qualification or a separate PQR. Supplementary essential variables apply when notch toughness testing is specified.

Q: How do I cite AWS D1.1 in a procedure or report?

AWS D1.1 is cited as 'AWS D1.1/D1.1M:2025 Structural Welding Code — Steel, American Welding Society, Miami, FL' in formal references. Within procedures, WPS forms, and inspection reports, the short form 'AWS D1.1:2025' is acceptable along with the specific clause, table, or figure being referenced — for example, 'per AWS D1.1:2025 Table 5.11' or 'per AWS D1.1:2025 Clause 8.9'. The /M suffix indicates the metric companion document — for SI unit projects use 'D1.1M:2025'. The 2025 edition is the current edition as of April 2026 and supersedes D1.1:2020. Drawings and contracts that reference 'AWS D1.1' without an edition default to the latest edition unless explicitly fixed (which is uncommon and requires explicit owner agreement). When a project transitions from one edition to the next, all related WPSs, PQRs, and inspector qualifications should be reviewed for any code changes that affect the work — see the dedicated AWS D1.1:2025 changes guide at /welding/aws-d1-1-2025-changes/ for the most-impactful 2025 updates.

AWS D1.1:2025 covers welded structural steel up to 100 ksi yield strength and 1/8-inch minimum thickness. Its 11 clauses cover scope, references, terms, design, prequalification, qualification, fabrication, inspection, tubular work, repair, and stud welding. Most projects use Clause 5 prequalified WPSs; non-standard joints need Clause 6 PQR testing.

Decision path: Use this quick reference to choose the governing D1.1 lane, then jump to the exact field check.

Scope

What AWS D1.1:2025 Covers

AWS D1.1:2025 Structural Welding Code — Steel applies to the design, fabrication, and inspection of welded structural steel construction. The code's scope per Clause 1.1 covers carbon and low-alloy steels with a minimum specified yield strength up to 100 ksi (690 MPa) and base metal thickness 1/8 inch (3 mm) or greater.

Materials and structures NOT covered by D1.1: sheet steel under 1/8 inch (use D1.3), stainless steel (use D1.6), aluminum (use D1.2), reinforcing bar (use D1.4), bridges with cyclic loading or fracture-critical members (use D1.5). Tubular structures are covered in Clause 9 of D1.1 with cross-references to the main body. Stud welding is covered in Clause 11.

Calculate D1.5 Bridge Preheat →

Welding processes covered: Shielded Metal Arc (SMAW), Gas Metal Arc (GMAW), Flux-Cored Arc (FCAW gas-shielded and self-shielded), Submerged Arc (SAW), Gas Tungsten Arc (GTAW), and Electroslag/Electrogas (ESW/EGW). Each process has its own essential variables in Tables 5.5 (prequalified) and 6.6 through 6.10 (qualified).

Per AWS D1.1:2025 Clause 1.1.1: “This code contains the requirements for fabricating and erecting welded steel structures. When this code is stipulated in contract documents, conformance with all provisions of the code shall be required, except for those provisions that the Engineer or contract documents specifically modifies or exempts.”

— AWS D1.1/D1.1M:2025, Structural Welding Code — Steel

Structure

The 11 Clauses of AWS D1.1:2025

Clause	Title	Covers
Clause 1	General Requirements	Scope, applicability, units, base metals covered
Clause 2	Normative References	Referenced standards (AWS A2.4, A3.0, A5 series, ASTM)
Clause 3	Terms and Definitions	Welding terminology defined per AWS A3.0
Clause 4	Design	Allowable stresses, joint design, fillet/groove sizing, fatigue
Clause 5	Prequalification of WPSs	Joint details, materials, parameters accepted by reference (no testing)
Clause 6	Qualification	PQR procedure, qualification testing, welder/operator qualification
Clause 7	Fabrication	Cutting, fit-up, preheat application, welder workmanship
Clause 8	Inspection	Inspector qualifications (CWI per QC1), VT, NDT, acceptance criteria
Clause 9	Tubular Structures	Specific provisions for hollow section connections (HSS, pipe)
Clause 10	Strengthening and Repair	Existing structure modifications, weld repair procedures
Clause 11	Stud Welding	Drawn-arc and capacitor-discharge stud welding requirements

The lifecycle order — design (4), prequalification or qualification (5/6), fabrication (7), inspection (8) — reflects the order operations are typically performed on a project. Specialty clauses 9, 10, and 11 augment the main body for specific construction types.

Key Tables

Most-Cited Tables in D1.1:2025

Table 5.7 — Filler Metal Requirements (Prequalified)

Table 5.7 matches base metal groups from Table 5.6 to allowable filler metal classifications per AWS A5 specifications. For Category A and B steels, low-hydrogen E70xx series electrodes are typically required for SMAW. For Category C and D, supplementary low-hydrogen and chemistry restrictions apply. The filler metal must match or under-match the base metal per the strength compatibility rules in §5.7.1.

Table 5.11 — Minimum Preheat and Interpass Temperature (Prequalified)

Table 5.11 is the most-referenced table in D1.1 for shop floor work. It specifies minimum preheat in degrees Fahrenheit and Celsius, organized by base metal group, welding process group, and base metal thickness range. Per §5.11, preheat is required when the values in Table 5.11 are above ambient temperature. Failure to apply preheat is the single most common cause of underbead cracking in carbon steel welds. Use the preheat calculator for instant per-steel lookups.

Table 7.7 — Minimum Fillet Weld Size

Table 7.7 specifies minimum fillet weld leg size based on base metal thickness:

Find Minimum Fillet Weld Size →

Base Metal Thickness (T)	Minimum Fillet Leg
T ≤ 1/4 inch [T ≤ 6 mm]	1/8 inch (3 mm)
1/4 < T ≤ 1/2 inch [6 < T ≤ 12 mm]	3/16 inch (5 mm)
1/2 < T ≤ 3/4 inch [12 < T ≤ 20 mm]	1/4 inch (6 mm)
3/4 inch < T [20 mm < T]	5/16 inch (8 mm)

Per Footnote A, T is the thicker part for non-low-hydrogen single-pass; T is the thinner part for low-hydrogen processes. Per Footnote C, 3/16 inch [5 mm] is the minimum for cyclically loaded structures; it raises the first-row 1/8 inch value and does not cap thicker-material rows.

Table 8.1 — Visual Inspection Acceptance Criteria

Table 8.1 specifies visual acceptance criteria for fillet, CJP, and PJP welds, separated by static vs cyclic loading. Cracks of any size are unacceptable in both load conditions. Undercut limits are 1/32 inch maximum for static, 1/100 inch for cyclic per direction-of-stress rules. Porosity individual pore diameter limit is 1/32 inch with frequency limits per the table footnotes. Per §8.9, all visual inspection shall be performed by a qualified inspector per Clause 8.1.4 — typically a CWI per AWS QC1.

Steel Groups

Base Metal Groups (Table 5.6)

D1.1:2025 uses the steel Group I–V system in Table 5.6 (per § 5.3 Base Metal) for prequalified base metals. The groups are not the same as the Category A through G rows used inside Table 5.11 for preheat, and they are not the fatigue stress categories A through F in Table 4.5.

Group	Typical Yield Range	Examples
Group I	Mostly 30-50 ksi	A36 ≤ 3/4 in, A53 Gr B, A106 Gr B, A500 Gr B/C
Group II	Mostly 36-60 ksi	A36 all thicknesses, A572 Gr 50/55, A588, A992
Group III	Mostly 60-70 ksi	A572 Gr 60/65, A913 Gr 60/65, A1066 Gr 60/65
Group IV	70 ksi	A709 HPS70W, A913 Gr 70, A1066 Gr 70
Group V	80 ksi	A913 Gr 80

Each group has matching filler-metal options in Table 5.7; Table 5.11 then sets preheat by process/category/thickness. Knowing the Table 5.6 group is the first step in selecting a prequalified WPS — wrong group means wrong filler metal and can also drive wrong preheat selection.

WPS Selection

Prequalified vs Qualified WPS — Decision Logic

Per Clause 5, a prequalified WPS uses a joint, base metal, filler metal, and parameters that the code accepts as qualified by reference. To use a prequalified WPS, ALL of the following must hold:

Joint matches Figures 5.1 through 5.10 (over 100 prequalified joint details)
Base metal is in Table 5.6 (one of the approved Groups I-V)
Filler metal matches Table 5.7 for the base metal group
Preheat meets Table 5.11 minimum for category, process group, and thickness
All essential variables stay within Table 5.5 ranges per §5.5

If any prequalified condition cannot be met, a qualified WPS per Clause 6 is required. The contractor performs a Procedure Qualification Record (PQR) — weld a test coupon to the proposed parameters, then perform qualification testing per Tables 6.2 through 6.5, as applicable to the joint type. The PQR validates the specific parameter combination, and the resulting WPS is qualified for production use within the essential variable ranges of Tables 6.6 through 6.10.

Field tip: Always check prequalification first. PQR testing typically costs $2,000-$5,000 per procedure. If your joint is in Figure 5.1 to 5.10 and your steel is in Table 5.6, prequalification is the cheaper, faster path. Custom joints and high-strength steels (Group IV/V) almost always require Clause 6 qualification.

— CWI shop floor observation, structural fabricator, 2026

Inspection

Inspection Scope (Clause 8)

Per Clause 8, AWS D1.1:2025 inspection requirements cover three layers: visual inspection (VT), nondestructive testing (NDT), and inspector qualification.

Per §8.9, all welds shall be visually inspected. Visual inspection is performed by personnel meeting the qualification requirements of §8.1.4 — typically a Certified Welding Inspector (CWI) per AWS QC1, or an equivalent inspector qualification. VT is performed before any volumetric NDT per §8.13.

Per §8.13 and §8.14, NDT methods include radiographic testing (RT), ultrasonic testing (UT), magnetic particle testing (MT), and penetrant testing (PT). The contract documents specify which welds require NDT and which method. CJP welds in tension typically require either RT or UT per §8.14.5. Statically loaded structures may require less NDT than cyclically loaded.

Acceptance criteria per Table 8.1 for VT, Table 8.2 for tension-loaded welds (RT/UT), and Table 8.3 for compression-loaded welds. The CWI's authority and responsibilities are defined in §8.1 through §8.4 — the inspector verifies WPS, monitors fit-up and welding, performs VT, witnesses or reviews NDT, and signs off on weld acceptance.

Citation

How to Cite AWS D1.1 in Procedures and Reports

Formal references: AWS D1.1/D1.1M:2025 Structural Welding Code — Steel, American Welding Society, Miami, FL. The /D1.1M suffix indicates the metric companion document — for SI unit projects use D1.1M:2025.

Within procedures, WPS forms, and inspection reports, the short form AWS D1.1:2025 is acceptable along with the specific clause, table, or figure being referenced. Examples of acceptable inline citations:

per AWS D1.1:2025 Table 5.11 — preheat reference
per AWS D1.1:2025 §8.9 — inspection scope reference
per AWS D1.1:2025 Clause 6.2.1 — PQR testing reference
per AWS D1.1:2025 Figure 5.4 — prequalified joint reference

The 2025 edition is the current edition as of April 2026 and supersedes D1.1:2020. Drawings and contracts that reference “AWS D1.1” without an edition default to the latest edition unless explicitly fixed (uncommon and requires explicit owner agreement). When a project transitions from one edition to the next, all related WPSs, PQRs, and inspector qualifications should be reviewed for any code changes that affect the work — see the dedicated AWS D1.1:2025 changes guide for the most-impactful 2025 updates.

Frequently Asked

AWS D1.1:2025 — FAQ

What does AWS D1.1:2025 cover?

AWS D1.1:2025 Structural Welding Code — Steel covers the design, fabrication, and inspection requirements for welded structural steel construction. It applies to carbon and low-alloy steels with a minimum specified yield strength up to 100 ksi (690 MPa) and base metal thickness 1/8 inch (3 mm) or greater. The code is referenced by AISC 360 Specification for Structural Steel Buildings and by most state DOT bridge specifications for non-fracture-critical work. The code covers SMAW (stick), GMAW (MIG), FCAW (flux core), SAW (submerged arc), GTAW (TIG), and ESW/EGW (electroslag/electrogas) processes. It does not cover sheet steel under 1/8 inch (governed by D1.3), stainless steel (D1.6), aluminum (D1.2), reinforcing bar (D1.4), bridges with cyclic loading or fracture-critical members (D1.5), or tubular structures (Clause 9 of D1.1 with cross-references to D1.1 main body). The 11 clauses are organized by lifecycle: scope, normative references, terms, design (Clauses 4 and 9), prequalification (5), qualification (6), fabrication (7), inspection (8), and three specialty clauses (9 tubular, 10 strengthening/repair, 11 stud welding).

What is the difference between Clause 5 and Clause 6 in D1.1?

Clause 5 of AWS D1.1:2025 covers prequalified Welding Procedure Specifications — joint configurations, materials, and parameters that the code accepts as qualified by reference, eliminating the need for procedure qualification testing. Clause 5 includes prequalified joint details (Figures 5.1 through 5.10), prequalified base metal groups (Table 5.6), prequalified filler metal classifications (Table 5.7), preheat requirements (Table 5.11), and essential variables for prequalified WPSs (Table 5.5). Clause 6 covers procedure qualification testing — when prequalification is not applicable (non-prequalified joint, non-prequalified material, or essential variable outside prequalified ranges), the contractor must perform a Procedure Qualification Record (PQR) per Clause 6.2.1 to qualify a WPS. Clause 6 includes test specimen requirements (Figures 6.1 through 6.18), WPS qualification test specimen requirements (Tables 6.2 through 6.5), and the essential variables that govern PQR scope (Tables 6.6 through 6.10 by process). The practical rule: if you can build to Clause 5 with prequalified WPS, do so — it eliminates testing cost. If your joint or material falls outside prequalification, you need a PQR per Clause 6.

What is AWS D1.1 Table 5.11?

AWS D1.1:2025 Table 5.11 specifies minimum preheat and interpass temperatures for prequalified WPSs. The table is organized by Table 5.11 preheat category/process rows, welding process group, and base metal thickness range. Each row gives the minimum preheat in degrees Fahrenheit and Celsius. For example, Category B steel (most common A36, A572 Gr 50) welded with low-hydrogen process at thickness over 3/4 inch through 1-1/2 inch requires 50°F (10°C) minimum preheat. Footnotes A through E define exceptions including minimum preheat for restraint conditions, the relationship between preheat and interpass temperature (per Clause 7.6.5, minimum interpass equals minimum preheat), and the exception for bridges where supplementary requirements may apply. Per AWS D1.1:2025 §5.11, preheat is required for all welding when the values in Table 5.11 are above ambient temperature. Failure to maintain minimum preheat is the single most common cause of underbead cracking in carbon steel welds. Use the Clause5 preheat calculator at /welding/preheat-calculator/ for instant per-steel lookups.

What is AWS D1.1 Table 7.7?

AWS D1.1:2025 Table 7.7 specifies minimum fillet weld sizes based on base metal thickness. The table has four rows: T less than or equal to 1/4 inch requires 1/8 inch minimum fillet leg; T greater than 1/4 inch and less than or equal to 1/2 inch requires 3/16 inch minimum; T greater than 1/2 inch and less than or equal to 3/4 inch requires 1/4 inch minimum; T greater than 3/4 inch requires 5/16 inch minimum. Per Footnote A, T equals the thicker part joined for non-low-hydrogen processes without preheat (single-pass required), but T equals the thinner part joined for low-hydrogen processes and non-low-hydrogen with cracking prevention per Clause 6.8.4. Per Footnote B, the minimum fillet size need not exceed the thinner part thickness. Per Footnote C, 3/16 inch [5 mm] is the minimum for cyclically loaded structures; it raises the first-row 1/8 inch value and does not cap thicker-material rows. These minimums exist to prevent underbead cracking caused by insufficient heat input into thick base metal — too small a fillet on thick plate cools too quickly, locking in residual stresses and hydrogen. For edges 1/4 inch or thicker, the maximum fillet size is material thickness minus 1/16 inch per Clause 4.5.2.9.

What is AWS D1.1 Table 8.1?

AWS D1.1:2025 Table 8.1 specifies visual inspection acceptance criteria for fillet welds, complete joint penetration (CJP) groove welds, and partial joint penetration (PJP) groove welds, separated by statically loaded vs cyclically loaded structures. The table covers crack acceptance (cracks of any size are unacceptable for both static and cyclic), weld profile (acceptable convex profile per Figures 8.4 through 8.6), undersize tolerance (5% of weld length may be undersize per the diminished-thickness rule), undercut (1/32 inch maximum for static, 1/100 inch for cyclic per direction-of-stress rules), porosity (1/32 inch maximum diameter for individual pores, with frequency limits), and fusion (complete fusion required, no incomplete fusion at root or sidewall). Per AWS D1.1:2025 §8.9, all visual inspection shall be performed by personnel meeting the qualification requirements of Clause 8.1.4 — typically a Certified Welding Inspector (CWI) per AWS QC1 or an equivalent inspector qualification. Visual inspection is performed before any volumetric NDT (UT or RT) per Clause 8.13.

What are the base metal groups in AWS D1.1?

AWS D1.1:2025 Table 5.6 lists approved prequalified base metals in Groups I through V by specification, grade, thickness limits, yield strength, and tensile range. Groups I through V include approved steels such as A36, A53 Gr B, A500 Gr B/C, A572 Gr 50/60/65, A588, A709 HPS70W, A913 Gr 60/65/70/80, A992, and A1066. Table 5.7 selects matching filler metals by base-metal group. Table 5.11 then sets preheat by its own process/category/thickness rows, so the practical lookup path is: identify the Table 5.6 group, choose a Table 5.7 filler metal, then apply Table 5.11 preheat.

What is the difference between prequalified and qualified WPS?

A prequalified WPS per AWS D1.1:2025 Clause 5 uses a joint configuration, base metal, filler metal, and welding parameters that the code accepts as qualified by reference. The contractor writes the WPS document but does not perform qualification testing — the code's body of historical test data substitutes for project-specific qualification. To use a prequalified WPS, all of the following must hold: joint matches Figures 5.1 through 5.10, base metal is in Table 5.6, filler metal matches Table 5.7 for the base metal group, preheat meets Table 5.11, and all essential variables stay within Table 5.5 ranges. A qualified WPS per Clause 6 is required when any of the prequalified conditions cannot be met. The contractor must perform a Procedure Qualification Record (PQR) — weld a test coupon to the proposed parameters, then perform qualification testing per Tables 6.2 through 6.5, as applicable to the joint type. The PQR validates the specific parameter combination and the resulting WPS is qualified for production use within the essential variable ranges of Tables 6.6 through 6.10. Prequalified is faster and cheaper; qualified is more flexible.

What welding processes does AWS D1.1 cover?

AWS D1.1:2025 covers six welding processes: Shielded Metal Arc Welding (SMAW, stick), Gas Metal Arc Welding (GMAW, MIG), Flux-Cored Arc Welding (FCAW, both gas-shielded FCAW-G and self-shielded FCAW-S), Submerged Arc Welding (SAW), Gas Tungsten Arc Welding (GTAW, TIG), and Electroslag and Electrogas Welding (ESW/EGW). Each process has its own essential variables in Tables 5.5 (prequalified) and 6.6 through 6.10 (qualified). SMAW and GMAW are the most common in structural fabrication. FCAW is dominant for in-position welding on heavy structural members. SAW is used for shop production of long welds (girders, beams). GTAW is used for root passes on critical CJP welds and for stainless overlay. ESW/EGW are specialty processes for very thick sections — note that ESW requires a project-specific qualification per §6.2.4 because of its high heat input characteristics. Note: Stud welding is covered separately in Clause 11. Resistance welding is not covered by D1.1; use AWS C1.1 for resistance spot welding of steel.

Where do I find essential variables for D1.1 WPS?

Essential variables for AWS D1.1:2025 prequalified WPSs are in Table 5.5, organized by welding process. For example, SMAW has essential variables including electrode classification (A5.1 or A5.5), electrode diameter (which determines amperage range), polarity (DCEP for low-hydrogen E70xx series), preheat (Table 5.11), interpass temperature (≥ minimum preheat per §7.6.5), travel speed (within prequalified ranges by joint type), and welding position. Essential variables for qualified WPSs are in Tables 6.6 (SMAW), 6.7 (SAW), 6.8 (GMAW/FCAW), 6.9 (GTAW), and 6.10 (ESW/EGW). The qualified-WPS essential variables are stricter and define the range over which a single PQR qualifies a WPS — for example, base metal thickness range qualified by a single PQR is the test coupon thickness ±25% (most processes, see Tables 6.6 through 6.10). Changes to essential variables require either re-qualification or a separate PQR. Supplementary essential variables apply when notch toughness testing is specified.

How do I cite AWS D1.1 in a procedure or report?

AWS D1.1 is cited as 'AWS D1.1/D1.1M:2025 Structural Welding Code — Steel, American Welding Society, Miami, FL' in formal references. Within procedures, WPS forms, and inspection reports, the short form 'AWS D1.1:2025' is acceptable along with the specific clause, table, or figure being referenced — for example, 'per AWS D1.1:2025 Table 5.11' or 'per AWS D1.1:2025 Clause 8.9'. The /M suffix indicates the metric companion document — for SI unit projects use 'D1.1M:2025'. The 2025 edition is the current edition as of April 2026 and supersedes D1.1:2020. Drawings and contracts that reference 'AWS D1.1' without an edition default to the latest edition unless explicitly fixed (which is uncommon and requires explicit owner agreement). When a project transitions from one edition to the next, all related WPSs, PQRs, and inspector qualifications should be reviewed for any code changes that affect the work — see the dedicated AWS D1.1:2025 changes guide at /welding/aws-d1-1-2025-changes/ for the most-impactful 2025 updates.

AWS D1.1 Full Guide → Preheat Calculator

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