Subsea and Topsides Facilities Installation

Table 14.8.2 below provides a summary of Contractor minimum work level in relation to Subsea and Topsides Facilities Installation.

Subsea Installation

• Laying shall be initiated from the Company approved starting locations, along the approved corridor or route and on to the intended termination points or target locations. Laying outside of the approved corridor or route is not permitted. Similarly subsea structures may only be positioned at the approved locations in an approved order.

• Pipeline and Flowline installation shall utilize the automatic method of welding pipe joints and AUT (Automatic Ultrasonic Testing) system on the lay barge. Installation tolerances, maximum tension and dead band setting shall be in accordance with Company specifications provided in Company Supplied Data and latest revision DNV OS F101.

• Stress in the pipeline and flowines shall be controlled during the

weakening of the lines.

• During laying, equipment which will ensure adequate line protection from external forces which might cause buckling, weakening or overstressing shall be provided as necessary.

• All equipment used in handling and cradling coated line pipe shall not damage the coating. Pipe shall be handled in a manner to prevent damage to the pipe walls and bevels. Damaged line pipe ends shall be re-beveled before welding.

• When laying is interrupted and abandonment of line is decided, the open end of the laid pipeline or flowline shall be securely closed and shall not be opened until laying is resumed. Any pipe end lowered in the water shall have watertight caps, installed with provisions for flooding and dewatering.

• In case of accidental water ingress any impacted sections shall be swabbed or pigged before that section is tied into the line, as per Company approved Contractor submitted procedure.

• A line pipe traceability management database, developed at the Engineering stage shall be further utilized during the laying sequence to record information such as joint number, mill/ heat number, joint details, anode details, and time and date of installation. At each welding station the key quality control details shall be recorded such as weld number, welder identification number, batch number of welding rods, weld procedure used, and final weld NDT results.

• Contractor shall be responsible for the loading of Subsea Umbilical as per defined in Exhibit J Company Furnished Material.

• Contractor shall perform all required offshore platform preparations prior to the J-tube pull of the umbilical. These preparations, shall include, but are not limited to:

• Installation and connection to utilities of umbilical pull-in winch

• Fitting of all sheaves and rigging

• Checking messenger lines and running pull-in cables

• Construction of all safety features, hand rails, scaffolding, work platforms etc necessary to perform the work.

• Installation of the umbilical shall be by a powered carousel and shall be initiated by means of a dead man anchor. The excess umbilical shall be deployed on the seabed as required to position the UTA suitable for pull in to the SDU/Tree or as per Subsea System Vendor guidance.

• Redundant safety features shall be integrated to prevent free

equipment shall be reversible and shall be able to pull the Umbilical back on board.

• During installation, the umbilical hoses and tubing shall be maintained with an internal pressure in accordance with the Umbilical Vendor’s installation guidelines. During the laying of the umbilical, the hydraulic tubes and electrical cables shall be continuously monitored. Contractor shall perform all the tests necessary at any stage of installation to demonstrate to Company’s satisfaction that the umbilical conforms to the specification requirements.

• Contractor shall provide umbilical jetting equipment for burial of the umbilical without impact to umbilical integrity. Equipment shall be suitable for the expected seabed conditions and soil bearing capacity. Jetting spread shall not sink during operation and shall bury the umbilical to a minimum depth of 0.5 m. Unburied umbilical/ Electrohydraulic flying leads shall be protected using bitumen mattresses.

• All equipment in contact with the Umbilical shall be selected and configured to prevent damage of the external sheath.

• During Umbilical pull in bellmouth entrance shall be continuously monitored by ROV. Only Chinese fingers and fit for purpose designed clamps shall be used to transfer the pulling loads to the Umbilical.

• Subsea equipment shall be free of projections, sharp edges or any structure that may pose a potential risk to ROV umbilical and/or tether.

• All rigging shall be certified and color coded in accordance with Contractor’s procedures.

Topsides Installation

• Contractor shall undertake lifting operations per the approved lifting procedures as listed in Exhibit G. Lifting Plans shall be submitted by Contractor for review and approval by Company.

• Storing inflammable and hazardous products, and the layout of construction equipment and its links (generator sets, compressors, welding sets) shall be defined so as not significantly to increase the level of risk to personnel and installations. They shall be marked on the project's installation drawing. Any equipment that is not essential to the work shall be returned or stowed away to keep the working areas clear.

• Contractor shall test, paint, install, passivate and clean all the interconnecting piping between equipment in accordance with the Project piping specifications.

Table 14.8.2: Subsea and Topsides Facilities Installation Basis