TIN MINH
AWS D1.1 Welding Standard: A Quality Control Guide for Steel Structures
Comprehensive guide to AWS D1.1 structural welding code: WPS/PQR requirements, NDT inspection methods, acceptance criteria, and how Tin Minh implements these standards.
What is AWS D1.1?
AWS D1.1 (Structural Welding Code - Steel) is the most widely used welding standard worldwide, published by the American Welding Society. It governs the welding of steel structures including industrial buildings, bridges, and heavy equipment.
In Vietnam, AWS D1.1 is required by most FDI companies and international contractors for large-scale steel fabrication projects in industrial zones across Dong Nai, Binh Duong, and Ho Chi Minh City.
Key Requirements of AWS D1.1
Welding Procedure Specification (WPS)
A WPS documents the essential variables for each weld joint:
- Base metal: Steel grade, thickness range, strength class
- Filler metal: AWS classification (e.g., E7018, ER70S-6)
- Welding parameters: Amperage, voltage, travel speed, heat input
- Position: 1G through 6G
- Thermal treatment: Preheat temperature, PWHT requirements
Procedure Qualification Record (PQR)
The PQR validates the WPS through actual testing:
- Tensile testing to verify joint strength
- Face and root bend tests for ductility
- Macro examination for weld profile
- Charpy impact testing when required by design
Welder Performance Qualification (WPQ)
Every welder must pass qualification tests matching the WPS they will use. Qualifications cover specific positions, joint types, thickness ranges, and must be renewed every 6 months if the welder has not been welding continuously.
NDT Inspection Methods
AWS D1.1 specifies non-destructive testing requirements based on joint type and structural importance:
| Method | Code | Application |
|---|---|---|
| Visual Testing | VT | Mandatory 100% on all welds |
| Ultrasonic Testing | UT | CJP groove welds, dynamically loaded structures |
| Radiographic Testing | RT | Pipe welds, pressure vessels |
| Magnetic Particle | MT | Surface crack detection on ferromagnetic materials |
| Liquid Penetrant | PT | Surface defect detection on non-magnetic materials |
Acceptance Criteria
AWS D1.1 defines clear pass/fail criteria:
- Porosity: Total area must not exceed 1% of weld cross-section
- Cracks: Zero tolerance - any crack is rejectable
- Slag inclusions: Total length limited based on material thickness
- Incomplete fusion: Not acceptable under any condition
How Tin Minh Implements AWS D1.1
At Tin Minh Technical Service Company, we maintain strict compliance with AWS D1.1 across all steel fabrication projects:
Qualified Personnel:
- AWS CWI (Certified Welding Inspector) on staff
- Welders qualified for 3G, 4G, and 6G positions
- QC inspectors trained in NDT Level II
Quality Management:
- Project-specific WPS development for each joint type
- PQR testing and complete documentation
- Welder qualification testing every 6 months
- 100% VT plus UT/RT per drawing requirements
- Welding Map tracking for every project
With over 14 years of experience and 200+ completed projects, Tin Minh delivers internationally certified weld quality for every structure.
Contact us: +84 251 629 3939 | [email protected]