AWS D1.1:2025 Quick Reference
Single-page summary of AWS D1.1:2025 構造溶接コード — Steel. All 11 clauses, the most-cited tables (5.7, 5.11, 7.7, 8.1), 事前認定 vs qualified rules, steel categories, and 検査 scope. For fast lookups on the shop floor or in the 検査員 booth.
AWS D1.1:2025 covers welded 構造用鋼 up to 100 ksi yield 強度 and 1/8-inch 最小 板厚. The 11 clauses are organized by lifecycle: scope, references, terms, design, prequalification, qualification, 製作, inspection, plus three specialty clauses (tubular, strengthening/補修, stud 溶接). Most projects use prequalified WPSs per 条項 5; non-規格 joints require Clause 6 PQR 試験.
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 基準'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 母材 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), ステンレス鋼 (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.
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 要求事項 for fabricating and erecting welded steel structures. When this code is stipulated in 契約図書, 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 溶接コード — SteelThe 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, 継手設計, fillet/groove sizing, fatigue |
| Clause 5 | Prequalification of WPSs | Joint details, materials, parameters accepted by reference (no testing) |
| Clause 6 | Qualification | PQR procedure, 機械試験, 溶接士/operator qualification |
| Clause 7 | Fabrication | Cutting, fit-up, 予熱 application, welder workmanship |
| Clause 8 | Inspection | Inspector qualifications (CWI per QC1), VT, NDT, 合否基準 criteria |
| Clause 9 | Tubular Structures | Specific provisions for hollow section connections (HSS, pipe) |
| Clause 10 | Strengthening and Repair | Existing structure modifications, 溶接 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 種類.
Most-Cited Tables in D1.1:2025
Table 5.7 — 溶加材 Requirements (Prequalified)
Table 5.7 matches base metal categories from 表 5.3 to allowable filler metal classifications per AWS A5 specifications. For カテゴリー A and B steels, 低水素 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 パス間温度 (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 category, 溶接工程 group, and base metal 厚さ範囲. Per §5.11, preheat is required when the values in Table 5.11 are above ambient 温度. Failure to apply preheat is the single most common cause of underbead cracking in 炭素鋼 welds. Use the preheat calculator for instant per-steel lookups.
Table 7.7 — Minimum すみ肉溶接 Size
Table 7.7 specifies minimum すみ肉溶接の脚長 サイズ based on base metal thickness:
| Base Metal Thickness (T) | Minimum Fillet Leg |
|---|---|
| Up to 1/4 inch (6 mm) | 1/8 inch (3 mm) |
| Over 1/4 to 1/2 inch (6 to 13 mm) | 3/16 inch (5 mm) |
| Over 1/2 to 3/4 inch (13 to 19 mm) | 1/4 inch (6 mm) |
| Over 3/4 inch (19 mm) | 5/16 inch (8 mm) |
Per Footnote A, T is the thicker part for 非低水素 single-pass; T is the thinner part for low-hydrogen processes. Per Footnote C, a 3/16-inch cap applies for cyclically 読み込み済み structures regardless of thickness.
Table 8.1 — 外観検査 Acceptance Criteria
Table 8.1 specifies 目視 受入基準 for fillet, CJP, and PJP welds, separated by static vs cyclic loading. 割れ of any size are unacceptable in both load conditions. アンダカット 限界値 are 1/32 inch 最大 for static, 1/100 inch for cyclic per direction-of-stress rules. 気孔 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.
Base Metal Categories (Table 5.3)
AWS D1.1:2025 Table 5.3 groups prequalified base metals into four categories based on chemistry and yield strength.
| Category | Yield Range | Examples |
|---|---|---|
| Category A | Up to 50 ksi | A36, A53 Gr B, A106 Gr B, A500 Gr B, A572 Gr 50 |
| Category B | Up to 60 ksi | A572 Gr 60, A588, A992 |
| Category C | Up to 70 ksi | A572 Gr 65, A709 Gr 50W, A709 Gr 70W |
| Category D | Over 70 ksi | A514, A709 Gr HPS 70W, A913 Gr 65/70/80 |
Each category has its own preheat requirements in Table 5.11, filler metal restrictions in Table 5.7, and 重要変数 ranges in Table 5.5. Higher categories require higher preheat and stricter low-hydrogen practice. Knowing the category is the first step in selecting a 事前認定WPS — wrong category means wrong preheat and risk of cracking.
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 5.3 (one of the four categories above)
- Filler metal matches Table 5.7 for the base metal category
- 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 施工業者 performs a 溶接施工法確認試験記録 (PQR) — weld a 試験片 to the proposed parameters, then perform mechanical testing per Table 6.4 (tension, bend, optional CVN). 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 5.3, prequalification is the cheaper, faster path. Custom joints and high-strength steels (Category D) almost always require Clause 6 qualification.
— CWI shop floor observation, structural 製作者, 2026Inspection 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 認定溶接検査員 (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 放射線透過試験 (RT), 超音波探傷試験 (UT), 磁粉探傷試験 (MT), and 浸透探傷 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.
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 referenceper AWS D1.1:2025 §8.9— inspection scope referenceper AWS D1.1:2025 Clause 6.2.1— PQR testing referenceper 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.