27 real Project & Commissioning questions from the Plant Operations bank, as asked in Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd — free to start.
1. What is Pre-commissioning?
Junior
A.low-pressure air or nitrogen test with soap solution or helium after reassembly to confirm joint tightness before hydrocarbon introduction
B.activities after mechanical completion such as flushing, cleaning, hydrotest, loop check and motor solo run, before process fluids are introduced
C.catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
D.run at design rate, typically 72 hours, proving capacity, product quality and specific consumption against licensor guarantees before final acceptance
2. Which term means: "activities after mechanical completion such as flushing, cleaning, hydrotest, loop check and motor solo run, before process fluids are introduced"?
A.Pre-commissioning — activities after mechanical completion such as flushing, cleaning, hydrotest, loop check and motor solo run, before process fluids are introduced
B.Pre-commissioning — low-pressure air or nitrogen test with soap solution or helium after reassembly to confirm joint tightness before hydrocarbon introduction
C.Pre-commissioning — catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
D.Pre-commissioning — dividing the plant into systems and sub-systems, utilities first and process last, so handover, testing and start-up are sequenced
A.end-to-end verification of each instrument loop from field device to DCS display and final element, with signal injection at 0, 50 and 100%
B.pressure test with water at 1.5 times design pressure for B31.3 piping or 1.3 times MAWP for ASME VIII vessels, held for a set time
C.catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
D.dividing the plant into systems and sub-systems, utilities first and process last, so handover, testing and start-up are sequenced
5. Which term means: "pressure test with water at 1.5 times design pressure for B31.3 piping or 1.3 times MAWP for ASME VIII vessels, held for a set time"?
A.Hydrotest — dividing the plant into systems and sub-systems, utilities first and process last, so handover, testing and start-up are sequenced
B.Hydrotest — pressure test with water at 1.5 times design pressure for B31.3 piping or 1.3 times MAWP for ASME VIII vessels, held for a set time
C.Hydrotest — low-pressure air or nitrogen test with soap solution or helium after reassembly to confirm joint tightness before hydrocarbon introduction
D.Hydrotest — run at design rate, typically 72 hours, proving capacity, product quality and specific consumption against licensor guarantees before final acceptance
A.high-velocity water or air blowing of lines and acid or alkali cleaning of boilers and compressor suction lines to remove mill scale and debris
B.end-to-end verification of each instrument loop from field device to DCS display and final element, with signal injection at 0, 50 and 100%
C.catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
D.register of incomplete or defective items at mechanical completion, categorised A (must fix before start-up) and B (can be done after)
8. Which term means: "end-to-end verification of each instrument loop from field device to DCS display and final element, with signal injection at 0, 50 and 100%"?
A.Loop check — end-to-end verification of each instrument loop from field device to DCS display and final element, with signal injection at 0, 50 and 100%
B.Loop check — high-velocity water or air blowing of lines and acid or alkali cleaning of boilers and compressor suction lines to remove mill scale and debris
C.Loop check — pressure test with water at 1.5 times design pressure for B31.3 piping or 1.3 times MAWP for ASME VIII vessels, held for a set time
D.Loop check — low-pressure air or nitrogen test with soap solution or helium after reassembly to confirm joint tightness before hydrocarbon introduction
11. Which term means: "register of incomplete or defective items at mechanical completion, categorised A (must fix before start-up) and B (can be done after)"?
A.Punch list — catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
B.Punch list — register of incomplete or defective items at mechanical completion, categorised A (must fix before start-up) and B (can be done after)
C.Punch list — pressure test with water at 1.5 times design pressure for B31.3 piping or 1.3 times MAWP for ASME VIII vessels, held for a set time
D.Punch list — low-pressure air or nitrogen test with soap solution or helium after reassembly to confirm joint tightness before hydrocarbon introduction
A.pressure test with water at 1.5 times design pressure for B31.3 piping or 1.3 times MAWP for ASME VIII vessels, held for a set time
B.catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
C.high-velocity water or air blowing of lines and acid or alkali cleaning of boilers and compressor suction lines to remove mill scale and debris
D.activities after mechanical completion such as flushing, cleaning, hydrotest, loop check and motor solo run, before process fluids are introduced
14. Which term means: "high-velocity water or air blowing of lines and acid or alkali cleaning of boilers and compressor suction lines to remove mill scale and debris"?
A.Flushing and chemical cleaning — end-to-end verification of each instrument loop from field device to DCS display and final element, with signal injection at 0, 50 and 100%
B.Flushing and chemical cleaning — run at design rate, typically 72 hours, proving capacity, product quality and specific consumption against licensor guarantees before final acceptance
C.Flushing and chemical cleaning — low-pressure air or nitrogen test with soap solution or helium after reassembly to confirm joint tightness before hydrocarbon introduction
D.Flushing and chemical cleaning — high-velocity water or air blowing of lines and acid or alkali cleaning of boilers and compressor suction lines to remove mill scale and debris
A.end-to-end verification of each instrument loop from field device to DCS display and final element, with signal injection at 0, 50 and 100%
B.catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
C.low-pressure air or nitrogen test with soap solution or helium after reassembly to confirm joint tightness before hydrocarbon introduction
D.dividing the plant into systems and sub-systems, utilities first and process last, so handover, testing and start-up are sequenced
17. Which term means: "low-pressure air or nitrogen test with soap solution or helium after reassembly to confirm joint tightness before hydrocarbon introduction"?
A.Leak test — run at design rate, typically 72 hours, proving capacity, product quality and specific consumption against licensor guarantees before final acceptance
B.Leak test — low-pressure air or nitrogen test with soap solution or helium after reassembly to confirm joint tightness before hydrocarbon introduction
C.Leak test — catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
D.Leak test — high-velocity water or air blowing of lines and acid or alkali cleaning of boilers and compressor suction lines to remove mill scale and debris
A.pressure test with water at 1.5 times design pressure for B31.3 piping or 1.3 times MAWP for ASME VIII vessels, held for a set time
B.end-to-end verification of each instrument loop from field device to DCS display and final element, with signal injection at 0, 50 and 100%
C.dividing the plant into systems and sub-systems, utilities first and process last, so handover, testing and start-up are sequenced
D.run at design rate, typically 72 hours, proving capacity, product quality and specific consumption against licensor guarantees before final acceptance
20. Which term means: "run at design rate, typically 72 hours, proving capacity, product quality and specific consumption against licensor guarantees before final acceptance"?
A.Performance guarantee test — activities after mechanical completion such as flushing, cleaning, hydrotest, loop check and motor solo run, before process fluids are introduced
B.Performance guarantee test — pressure test with water at 1.5 times design pressure for B31.3 piping or 1.3 times MAWP for ASME VIII vessels, held for a set time
C.Performance guarantee test — catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
D.Performance guarantee test — run at design rate, typically 72 hours, proving capacity, product quality and specific consumption against licensor guarantees before final acceptance
A.catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
B.end-to-end verification of each instrument loop from field device to DCS display and final element, with signal injection at 0, 50 and 100%
C.dividing the plant into systems and sub-systems, utilities first and process last, so handover, testing and start-up are sequenced
D.pressure test with water at 1.5 times design pressure for B31.3 piping or 1.3 times MAWP for ASME VIII vessels, held for a set time
23. Which term means: "dividing the plant into systems and sub-systems, utilities first and process last, so handover, testing and start-up are sequenced"?
A.System-wise commissioning — run at design rate, typically 72 hours, proving capacity, product quality and specific consumption against licensor guarantees before final acceptance
B.System-wise commissioning — high-velocity water or air blowing of lines and acid or alkali cleaning of boilers and compressor suction lines to remove mill scale and debris
C.System-wise commissioning — dividing the plant into systems and sub-systems, utilities first and process last, so handover, testing and start-up are sequenced
D.System-wise commissioning — register of incomplete or defective items at mechanical completion, categorised A (must fix before start-up) and B (can be done after)
A.catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
B.register of incomplete or defective items at mechanical completion, categorised A (must fix before start-up) and B (can be done after)
C.end-to-end verification of each instrument loop from field device to DCS display and final element, with signal injection at 0, 50 and 100%
D.pressure test with water at 1.5 times design pressure for B31.3 piping or 1.3 times MAWP for ASME VIII vessels, held for a set time
26. Which term means: "catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning"?
A.First fill and commissioning spares — run at design rate, typically 72 hours, proving capacity, product quality and specific consumption against licensor guarantees before final acceptance
B.First fill and commissioning spares — dividing the plant into systems and sub-systems, utilities first and process last, so handover, testing and start-up are sequenced
C.First fill and commissioning spares — low-pressure air or nitrogen test with soap solution or helium after reassembly to confirm joint tightness before hydrocarbon introduction
D.First fill and commissioning spares — catalyst, resins, lubricants, chemicals and start-up spares budgeted separately from operating spares and procured to arrive before pre-commissioning
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