The startup of a new installation, as well as the restarting of an existing one after significant modification works or complete revamping, is a delicate and complex matter. It entails extensive as well as systematic tests and verifications, following a precise sequence.
The number of essential tasks to be achieved between the end of construction and the actual start-up is defined as precommissioning and commissioning activities.
The TRA methodology precisely details and specifies all technical and organizational aspects of these activities, in order to guarantee that the facility is delivered safely and as per engineering requirements, in the shortest possible schedule.
The precommissioning phase, following the end of construction, include conformity checks and a complete set of static (de-energized) tests which aim to verify that every piece of equipment is built and installed as per design.
The commissioning phase is the next and last critical verification step before the introduction of hydrocarbon feedstock into a facility. It feature a series of functional testing (energized) and operational dynamic tests as well as running-in and on-line tests of all utilities prior to start-up.
The actual start-up corresponds to the introduction of hydrocarbons into the plant. This delicate mission is usually carried out by the operations team, assisted by the commissioning team.
TRA precommissoning and commissioning methodology is based on the "System Approach". It requires a careful and thorough partition of the facility into systems and subsystems during the preparation phase. This particular organization allows various tasks belonging to construction, precommissioning or commissioning activities to be undertaken and completed in parallel. While optimizing means and resources, the process is time-saving and practical.
Precommissioning activities include the checking and testing of each item of equipment or component, in all disciplines (electrical, instrumentation, telecom, mechanical, safety, HVAC, piping).
The Pre-Commissioning phase includes three main type of activities :
- Conformity checks: instrument calibration consistency to data sheets requirements, review of electrical devices certification for installation in hazardous area, comformity of cables connections in junctions boxes compared to engineering documents, verification that filters have been mounted in prior direction, etc...
- Static / de-energized tests: control of machinery alignment, cable electrical insulation and continuity, PSV setting check on calibration bench, etc...
- Piping tests (test Packs), including conformity to isometrics and PIDs, NDT review, pressure hydrotests, piping network gross air leak test, etc..
All defects and non conformities detected on site are assigned a critical code and priority level and recorded in a punch list data base. When cleared and after verification and validation, punch list point are closed
On completion of these checks and tests, a precommissioning dossier for each subsystem, containing all check and test sheets, marked up drawings, FAT and tests reports, and all certificates, is reviewed and approved, and an "RFC" (Ready For Commissioning) certificates is issued.
The Commissioning phase essentially comprises three type of tasks :
- Functional tests (dynamic and energized verifications), such as instrumented safety loop checks, PAGA coverage tests, electrical switchboards powering up, etc...
- Operational tests, either mechanical (run tests of motors) or related to packages or main equipments (OTP), such as the testing of a turbo-generator, air compressors and driers or that of a separator control using subtitute fluids, etc... These OTPs are the most critical tests and will ensure that a whole subsystem is ready for operation.
- Pre start up activities, or preparation of the piping and vessels for start-up, including nitrogen / helium leak tests, chemicals first filling, etc...
During the whole phase, defects and non conformities are also managed through the punch list data base.
On completion of these tests, a commissioning dossier for each subsystem, including all tests sheets and records, is checked and approved, and an "RFSU" (Ready For Start Up) certificate is issued. The subsystem may then be transferred from the commissioning entity to the operations entity