Q1: What NDT method detects internal flaws in high-pressure boiler tubes (ASTM A213 T22)?
A: Ultrasonic testing (UT) is commonly used to detect inclusions, laminations, or voids.
Q2: Why is hydrostatic testing mandatory for API 5L X65 gas pipelines?
A: It validates structural integrity at 1.25-1.5 times MAOP (Maximum Allowable Operating Pressure).
Q3: How is intergranular corrosion testing performed on 321 stainless tubes?
A: ASTM A262 Practice E (Streicher Test) or Practice C (Huey Test) evaluates sensitization.
Q4: What is the required Charpy impact value for Arctic-grade API 5L X70?
A: Minimum 40J at -60°C per supplementary requirement SRL (Low Temperature).
Q5: How is wall thickness variation controlled in precision tubing?
A: Automated ultrasonic gauging during drawing or pilgering ensures ±5% tolerance for grades like 4130.
