Testing

Module from the Pressure Vessel Engineering Curriculum curriculum.

Module 8 - Pressure Testing and NDE · Learning Objectives · 1. Apply UG-99 hydrostatic test: P_test = 1.3 * MAWP * (S_test/S_design) · 2. Use UG-100 pneumatic test only when hydro is impracticable: P_test = 1.1 * MAWP * (S_test/S_design) · 3. Plan safe pneumatic testing with energy analysis (TNT equivalent, exclusion zone) · 4. Select NDE methods by fluid service: VT, MT/PT, RT, UT/PAUT · 5. Document and maintain U-1A data report for life of vessel · Hydrostatic Test Procedure · Heat water to minimum MDMT + 30 F (brittle fracture margin per UG-99). Vent all high points. Fill slowly. Hold at test pressure for minimum 10 minutes, then reduce to inspection pressure (MAWP or slightly higher) for visual examination of welds and joints. Verify gauge calibration. Re-test if any leak detected and repaired. · NDE by Joint Category

Joint Cat	Full RT (E=1.0)	Spot RT (E=0.85)	No RT (E=0.7)	PT/MT	Notes
A	Per UW-11(a)	Per UW-11(b)	Per UW-12(d)	Often PT	Long seam
B	Per UW-11(a)	Per UW-11(b)	Per UW-12(d)	Often PT	Circ seam
C	Per UW-11(a)(5)	-	Per UW-12	Often	Flange
D nozzles	Per UW-11(a)(4)	Per UW-11(b)	Per UW-12	PT or MT	Per code

Source: Pressure_Vessel_Engineering_Curriculum_v1.xlsx · Sheet: Testing

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