In the world of Non-Destructive Examination (NDE), complexity often grabs the headlines. Advanced methods like ultrasonic phased arrays or digital radiography dominate conference talks. However, the backbone of any quality assurance program—the method that finds the most surface defects for the least cost—is Visual Examination (VT) .
Within the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, the rules governing this critical process are found in ASME Section V, Article 9.
Whether you are a Level II examiner, a welding inspector, or a plant engineer, understanding the nuances of Article 9 is non-negotiable for Code compliance. This article provides a deep dive into the scope, acceptance criteria, examination requirements, and common pitfalls of ASME Section V Article 9. asme section v article 9
While acceptance criteria vary by Code Section, Article 9 directs you to identify specific discontinuities. The most common targets are:
Article 9 is famous for its quantifiable lighting requirements. "Looks bright enough" is not a legal defense. While acceptance criteria vary by Code Section, Article
Article 9 provides standard acceptance limits for visual examination, including:
| Discontinuity Type | Acceptance Limit (Illustrative) | |------------------|--------------------------------| | Cracks | Not allowed | | Incomplete fusion or penetration | Not allowed | | Undercut | ≤ 1/32 in. deep (except where larger is permitted by referencing code) | | Porosity | Size and distribution per code case | | Surface roughness | No sharp notches (smooth blend required) | Note: Always verify acceptance criteria with the governing
Note: Always verify acceptance criteria with the governing construction code (e.g., Section VIII, Div. 1). Article 9 may reference these or provide default values.