Effective Pre-Commissioning planning and initiation of PC. A Checklist for Pre-Commissioning of Offshore Facilities

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1 A Checklist for Pre-Commissioning of Offshore Facilities Effective Pre-Commissioning planning and initiation of PC activities provide a necessary bridge between earlier project execution phases, including Mechanical Completion, and the final commissioning and startup of the facility. PC can be an essential mark between the transition from a discipline-based approach to one that verifies the functionality of systems, regardless of their location on the facility. The planning required for an efficient Pre-Commissioning (PC) of an offshore facility is typically started during the early stages of detail design and commences immediately after Mechanical Completion (MC) has been achieved, which itself follows the engineering design and construction phases. Prior to initiating the PC actual work stage, the supervisor of the MC phase creates a formal document transferring the complete dossier of all activity of the system for handover to the Pre-Commissioning team, along with a register or punchlist that indicates any remaining MC work that still needs to be completed or closed out. Pre-Commissioning is Systems Driven Whereas Mechanical Completion includes the non-functional testing of equipment to confirm the integrity of its fabrication and installation to the intended design, Pre-Commissioning verifies the mechanical completion, the functionality of the system as well as calibration of the instrumentation to the facilities controls and control systems. While MC is completed by area or discipline, the Pre-Commissioning phase will be turned over to specialists who can address confirmation by system, ensuring that it is complete and ready for final Commissioning and startup. This phase can best commence efficiently after all of the components are in place so that systems, rather than individual pieces, can be verified. The PC contractor also engages the design engineering firm, vendors, manufacturers and operating personnel for support and their expertise. During the Pre-Commissioning effort, there can be many activities completed during the onshore phase and then moved offshore for completion of the system check-out. Where

2 Pre-commissioning addresses readiness by system rather than by individual pieces of equipment.

3 practical, piping should be power flushed and dried; communication systems tested to the fullest extent possible; instrument and electrical loops will be verified; instruments will undergo initial and final calibration; pumps can be operated where possible; motors verified for proper rotation and can be run and tested (burned in); and rotating equipment can receive initial (cold) alignments. The Pre-Commissioning phase is vital to schedule adherence of the project and a necessity in helping to minimize cost overruns. Ideally, PC activities should be planned as part of the construction and earlier project execution strategy so there can be a smooth transition from structural, mechanical, electrical, instrumentation and controls fabrication to systems checks where scheduled work is maximized. This time in the project is when potential flaws of construction, uncompleted tasks and system inadequacies can come to light and be addressed early enough to minimize schedule delays. Without a thorough Pre-Commissioning effort, potentially time-consuming and expensive modifications can go undone onshore, only to be addressed in a much more difficult offshore environment. Organization and Planning Are Key The selection of a Pre-Commissioning team is one of the most important milestones that will need to be addressed. The team will be responsible for planning and supplying the critical support and leadership during this project phase. The leadership as well as team members should, therefore, be experienced with the planning, tasks, schedule and project drivers regarding startup, as well as its complexities. After the project has determined the Scope of Work, the overall project schedule and startup drivers, an organization chart needs to be established, defining the overall hierarchy of how the PC team fits within the overall project management team. Additionally, a roles and responsibilities matrix required for the upcoming activities should be established. There will need to be separate designators in organizational charts created indicating location for the onshore and offshore PC work due to potential differences in contractual arrangements, transportation, personnel housing, parts availability and numerous other issues. Only after the scope of The pre-commissioning team is vital to maintaining project schedule

4 work and organizational plan is in place can the initial schedule be prepared, establishing the critical milestones for handing off systems to the commissioning and operations teams. These milestones are often how the PC team and their progress will be measured. The responsibility matrix is important to complement the organization definitions. The level of the matrices vary from broad to detailed, but its main use is to identify not only the scope of work and supply, but also the responsibility and Simultaneous Operations (SIMOPs) which may occur. For the purpose of this discussion, getting to the matrix level of PC and MC interface, along with the other SIMOPs is wise early enough to best identify any potential holes during the different phases of work. As discussed previously, identifying the location of the PC work plays an important role in the responsibility of certain activities and interfaces. For example, due to contractual limitations as well as schedule drivers, the onshore MC work will take priority and the facility where the work is being performed would be the driver. Whereas offshore the MC work may still be the priority, however the driver would be the Operator. The matrix, therefore, can identify not only the task but the responsibility of the work, whereas the details of the work are identified within the PC procedures and tracking database. In the initial planning of the PC stage, a critical path should be evaluated to establish the procedures that will be optimal to success. Although the best laid plans always have their obstacles, a plan must be established as a starting point. A detailed list of required activities would be created by the PC team and coupled with the data developed earlier in the project by engineering and managed through an electronic project information management system. The PC contractor is responsible for maintaining the data base, tracking progress critical for adhering to schedule and determining the status of the various activities. Reference data provided by engineering and the other delivery teams will need to be organized by the PC contractor according to the identified systems and should reside in a location accessible to all who will be utilizing it. Data includes, but is not limited to, PFDs, P&IDs, mechanical, electrical motor and ISA data sheets, instrument and electrical loop drawings, wiring plans and elevations for skids and modules, as well as the manufacturer s final data manuals for purchased equipment. A potential shortcoming is in not obtaining the interface data from outside of the topsides delivery team, e.g. subsea, export pipeline, communications, hull fabricators equipment. The key will be to provide a conscious effort to close these gaps early within the project so as not to impact the planned startup date. Successful PC work relies on detailed planning and defined responsibilities The PC work normally is broken down into discreet, manageable systems. The systems are separated according to the logical process flow, rather than by a package vendor. For example, a heat media system might include a fired unit, heat recovery unit, storage unit and pumps, along with interconnect piping, instrumentation, controls and electrical, all of which have likely been supplied by different vendors and reside on separate skids. This systems breakdown is the logical process to verify construction, confirm the integrity of the design, and prepare the system for handover to operations as the phase goes forward. The organization also allows for the commissioning of sub-systems within a system, without having to initiate work on the entire system. This avoids having to work around a finish to start on a system scenario, thus pushing the overall startup schedule past the desired outcome. The PC of utility systems is typically the first to be addressed and completed. This allows life support for the offshore personnel in addition to minimizing the need for additional components to PC the process systems later.

5 It is essential that good record keeping and a detailed preventative maintenance plan be initiated and carried out through handover to operations during the PC phase. A job or activity card system is an output of the existing database system, resulting as an archive to the work performed as an as built record. Task sheets record the subsystems and systems which have been completely pre- commissioned and ready for handover to be integrated into the facilities operating systems. In the overall PC work plan and prior to initiating the PC work, a meeting schedule should be established so that overall planning and progress can be regularly discussed and understood by all parties. Each of the participants should have a schedule that can be owned by them, reviewed intermittently by the team and adjusted accordingly, so that progress coincides among all team members. The critical path should be reviewed at a minimum weekly and recovery plans generated or updated as necessary. Deck space and personnel management are a critical part of offshore PC activities POB Management An important consideration in Pre-Commissioning is planning for the required number of personnel needed to undertake the offshore PC activities, the transportation requirements for the crews and their supplies, and the allocated personnel on board (POB) space to accommodate them. While working during the onshore phase space is somewhat unlimited with the exception of interfaces with Construction, offshore work presents a whole different set of challenges. Offshore, the PC team will have to work closely with all of the different work scopes onboard to understand each other s schedules and manpower requirements. These would include topsides Hookup and Commissioning (HUC), subsea flowline installation and testing contractors, and the export pipeline installation and testing contractors, as well as 3rd party vendors, communications personnel and Operations. During the offshore phase, depending upon timing and the hull type, a habitability inspection will be conducted by the U.S. Coast Guard or similar regulatory body. The work plan shall include in the overall schedule identifying work onshore, work offshore, work to achieve quarters habitation, Temporary Certificate of Inspection (TCOI), Final Certificate of Inspection (COI), and Handover to Operations. A variety of systems must be carefully planned for and put in place in order for approval of these various milestones. For TCOI these may include sufficient living quarters; temporary power generation; fire fighting, fire detection and suppression equipment; emergency evacuation equipment; potable water and sewage treatment provisions; and communications equipment. Planning for and precisely scheduling manpower is critical. If sufficient facilities are not available on the platform, floatels or other means for housing personnel might be required at a significant extra cost. The critical nature of the work being performed offshore compared with the other activities along with the schedule must be evaluated in depth to determine the cost/schedule benefit and work plan for utilizing a flotel. This also means weather limitations and transfer of personnel risks must be evaluated. Similarly, working space and delivery areas must be closely planned to accommodate the simultaneous operations (SIMOPS) being conducted during the pre-commissioning and subsequent commissioning operations. Conclusion In order for the PC segment to be successful, a good and detailed Pre-Commissioning/Commissioning plan should be developed, as early in the project as possible and good interface between all groups must be established. An experienced team, equipped with the necessary tools, data base, organizational structure, defined responsibilities and procedures, can assure that the Pre-Commissioning segment is efficient and can keep costs and schedule in-line with expectations. For more information concerning Mustang s capabilities in Mechanical Completion and Pre-Commissioning/Commissioning, contact Richard Shirley or Dan Vela at richard.shirley@ mustangeng.com or dan.vela@mustangeng.com.