Commissioning is the phase in an asset’s lifecycle, where its designed functions, guarantee-values and performances are being tested.
Formally, the commissioning phase starts after finalisation of the construction (or erection) phase, and is predecessor of the operations phase.
Practically, from experience, the commissioning preparation must start in the earliest phase: the ‘front-end loading (FEL)’ stages, to be able to already integrate relevant technical provisions in the early design stage, mandatory for a correct, safe and smooth commissioning.
Next to the determination of required technical provisions, also an adequate work breakdown structure shall be defined, as well as a chronological (or priority) finalisation order, to guide engineering, purchasing and construction to optimise the overall project time-schedule.
To enable the testing, the following typical activities take place throughout the commissioning phase:
- P&ID checks : constructed plant versus drawing check
- compliancy checks : installed material / temperature & pressure ratings
- instrument loop checking, from instrument to operator station
- electrical cable loop checking
- communication bus checking
- rotational equipment rotation-direction test
- pneumatic operated valves test & calibration
- motor operated valves test & end-limit / torque setting
- hydraulic operated valves test & calibration
- flushing / cleaning of systems, including chemical cleaning, steam blowing, mechanical cleaning
- first filling of systems with process media
- cold logic checks : programmed logical functions versus system descriptions checks
- hot logic checks : checking of logical functions with a running plant
- safeguarding tests : pressure relief valves lifting and re-seating setpoints, electrical protection relays, logical safety integrity level (SIL) tests
- Hazard and operability study : check on correct and complete implementation / integration of resolutions
- First test-runs, without and with process media as per design
- Verification of designed heat- and mass-balances
- Verification of operational procedures
- Training of operators & maintenance staff