Static Equipment Interview Questions Updated -

These questions test your basic understanding of design and components.

Q: Describe an RBI approach for static equipment.
A: Risk-Based Inspection (RBI) ranks equipment by likelihood and consequence of failure. Collect data (design, materials, process conditions, inspection history), assess degradation mechanisms, quantify risk, and define inspection intervals and techniques to reduce risk to acceptable levels. Update RBI based on inspection findings.

Key points: differentiation between prescriptive (code) and risk-based intervals, data quality, damage mechanisms (corrosion, creep, fatigue), documented follow-up actions.
Follow-up: What minimum data do you need to run an RBI assessment? static equipment interview questions updated

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This is a classic question to test code familiarity:

Q: Describe a time you identified a latent design issue in static equipment and how you resolved it.
A: Give a concise STAR answer: Situation (equipment X with thermal cycling), Task (reduce premature cracking), Action (ran FEA, identified nozzle fatigue, redesigned reinforcement and changed material, added supports), Result (reduced stress range by X%, extended inspection interval, no failures in Y years). These questions test your basic understanding of design

Key points: emphasize analysis, cross‑discipline communication, and measurable outcome.
Follow-up: Which FEA checks do you run for nozzle fatigue?

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Q: What is High-Temperature Hydrogen Attack (HTHA)? How do you detect it non-destructively?

Q: Explain "remaining life assessment" of a corroded vessel using API 579.

Q: For a fixed tubesheet heat exchanger (TEMA type AES), how do you prevent tube-to-tubesheet joint failure in thermal cycling?

Q: What is "sour service" and what are the latest NACE MR0175 limits for H₂S partial pressure?

Q: How do you perform a "pneumatic test" safely on a large column?

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Q: Given a cylindrical vessel: internal pressure 3.5 barg, design temp 60°C, internal diameter 1.2 m, using SA-516 Gr70 with allowable stress S=138 MPa, corrosion allowance 2 mm, joint efficiency E=0.85. Calculate required minimum shell thickness (ignore nozzle openings).
A: Use thin‑wall formula for cylindrical shell per ASME: t = (PR) / (SE - 0.6P) ; convert units: P = 3.5 bar = 0.35 MPa; R = 0.6 m.
Compute: numerator = 0.350.6 = 0.21 MPa·m; denominator = 1380.85 - 0.60.35 = 117.3 - 0.21 = 117.09 MPa. t = 0.21 / 117.09 = 0.001794 m = 1.79 mm. Add corrosion allowance 2 mm → 3.79 mm. Add minimum fabrication allowance/weld/rounding (use 6 mm minimum for practical manufacture per code) → use 6 mm shell thickness. This is a classic question to test code

Key points: show unit conversions, code minimums, practical fabrication minima.
Follow-up: How would the thickness change if pressure were doubled?

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