Overview
ISO 16338:2017 - "Welding for aerospace applications - Resistance spot and seam welding" - specifies requirements for resistance spot and seam welding used in aerospace structures and components. The standard sets out engineering, production and qualification requirements for processes, equipment, personnel and inspection where resistance welding affects the final product quality. It excludes resistance welding performed only as an intermediate operation (e.g., temporary tacking), resistance welding of dissimilar material group combinations, and does not address safety and health issues.
Key topics and technical requirements
ISO 16338:2017 covers the full lifecycle of resistance spot and seam welding activities relevant to aerospace manufacturing. Major technical topics include:
- Scope and exclusions - Clear limits on applicability (intermediate operations and dissimilar-material combinations are excluded).
- Terminology and symbols - Harmonized welding vocabulary referenced to ISO/TR 25901 and ISO 17677-1.
- Engineering and joint classification - Specific engineering requirements and classification of joints for spot and seam welds.
- Material groups and part preparation - Requirements for material grouping, cleaning, surface coatings and assembly prior to welding.
- Equipment and electrodes - Qualification and performance requirements for welding machines, electrodes, jigs and fixtures.
- Welding machine qualification - Methods, test pieces and reporting for machine qualification and periodic verification.
- Welding procedure (WPS) and WPQR - Determination of weld settings, WPS preparation, procedure qualification records (WPQR) and requalification rules.
- Personnel requirements - Competence, roles and responsibilities for welding coordination and operators.
- Production requirements and witness testing - Production controls, witness test specimens, parameter adjustment rules and alternate testing options.
- Inspection, testing and acceptance criteria - Visual, radiographic, metallographic and mechanical testing methods; criteria for nugget size, penetration, imperfections and electrode indentation.
- Test pieces and mechanical tests - Standard and special test-piece configurations and mechanical test methods for spot and seam welds.
Practical applications and who uses this standard
ISO 16338:2017 is intended for organizations involved in aerospace welding where resistance spot or seam welding directly affects product quality. Typical users include:
- Aerospace OEMs and tiered suppliers specifying welding requirements for airframe and subassembly production
- Welding engineers and process development teams establishing WPS/WPQR for resistance welding
- Quality managers and inspectors performing production witness testing, nondestructive testing (radiography) and acceptance assessments
- Manufacturing engineers responsible for machine qualification, fixtures and electrode selection
- Repair and overhaul facilities performing structural repairs when resistance welding is a final-process operation
Using ISO 16338 helps ensure consistent weld quality, traceability of qualifications, and alignment with aerospace procurement and certification expectations.
Related standards (examples)
- ISO 17677-1:2009 - Resistance welding vocabulary (spot, projection, seam)
- ISO/TR 25901 series - Welding vocabulary and processes
- ISO 6520-2 - Classification of geometric imperfections in welded metallic materials
- ISO 14731 - Welding coordination - Tasks and responsibilities
Keywords: ISO 16338, resistance spot welding, seam welding, aerospace welding standards, welding procedure specification (WPS), machine qualification, welding inspection, WPQR.