{"id":874,"date":"2014-01-01T10:33:06","date_gmt":"2014-01-01T02:33:06","guid":{"rendered":"http:\/\/alfanso10.esy.es\/?p=874"},"modified":"2017-04-24T18:27:12","modified_gmt":"2017-04-24T10:27:12","slug":"gaza-fso-slough-replacement","status":"publish","type":"post","link":"http:\/\/alfanso10.com\/?p=874","title":{"rendered":"GAZA FSO (Slough Replacement)"},"content":{"rendered":"<p>&nbsp;<\/p>\n<p><span style=\"color: #000000;\"><strong>COMPANY: EMAS-AMC<\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>PROJECT TITLE: GAZA FSO (Slough Replacement)<\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>CLIENT:\u00a0STX Offshore<\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>LOCATION:\u00a0Libya<\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>YEAR: 2014<\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>VESSEL: Subsea Construction Vessel Lewek Connector<\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>SCOPE OF WORK:<\/strong><\/span><\/p>\n<ul>\n<li><span style=\"color: #000000;\">Project Management and engineering<\/span><\/li>\n<li><span style=\"color: #000000;\">Procurement and fabrication of all temporary installation aids<\/span><\/li>\n<li><span style=\"color: #000000;\">All logistics, including receipt, storage and transport of permanent materials<\/span><\/li>\n<li><span style=\"color: #000000;\">Load-out, sea-fasten and transport all equipment to mobilisation location or to site<\/span><\/li>\n<li><span style=\"color: #000000;\">Perform all \u00a0survey \u00a0and \u00a0positioning, \u00a0including \u00a0pre-installation \u00a0and \u00a0post-installation \u00a0seabed surveys and associated works<\/span><\/li>\n<li><span style=\"color: #000000;\">Install nine (9) off 124mm diameter mooring anchor chains (3 x 3 cluster formation)<\/span><\/li>\n<li><span style=\"color: #000000;\">Install nine (9) off 84\u201d diameter anchor piles<\/span><\/li>\n<li><span style=\"color: #000000;\">Hook-up of all mooring chains to FSO turret and final tensioning of chains<\/span><\/li>\n<li><span style=\"color: #000000;\">Install one (1) Mid Water Arch (MWA) with gravity base \/ anchor piles<\/span><\/li>\n<li><span style=\"color: #000000;\">Install one (1) Pipeline End Manifold (PLEM)<\/span><\/li>\n<li><span style=\"color: #000000;\">Install one (1) J-tube for the Subsea Power \/ Optical Cable on DP4 Platform<\/span><\/li>\n<li><span style=\"color: #000000;\">Install one (1) I-tube for the Flexible Flowline on DP4 Platform<\/span><\/li>\n<li><span style=\"color: #000000;\">Install one (1) I\/J-Tube Protection Frame<\/span><\/li>\n<li><span style=\"color: #000000;\">Install two (2) 14.75\u201d ID and One (1) 10\u201d ID Dynamic risers from FSO turret to PLEM<\/span><\/li>\n<li><span style=\"color: #000000;\">Install one (1) Subsea Power \/ Optical Cable from DP4 Platform to FSO turret<\/span><\/li>\n<li><span style=\"color: #000000;\">Install one (1) 14.75\u201d ID Flexible Flowline from DP4 Platform to PLEM<\/span><\/li>\n<li><span style=\"color: #000000;\">Perform all subsea tie-ins for risers and flowline to PLEM<\/span><\/li>\n<li><span style=\"color: #000000;\">Perform all topside tie-ins for risers \/ flowline \/ power and optical cable at FSO turret and DP4 platform<\/span><\/li>\n<li><span style=\"color: #000000;\">Trenching for the Flexible Flowline<\/span><\/li>\n<li><span style=\"color: #000000;\">Install pipeline crossing supports and concrete mattresses at DP4 Platform location for Flexible Flowline and Power Cable<\/span><\/li>\n<li><span style=\"color: #000000;\">Perform all flowline and risers\u2019 pre-commissioning, including pigging\/flooding, back seal testing, and post installation leak test of all flowline\/risers<\/span><\/li>\n<li><span style=\"color: #000000;\">Perform Subsea Power \/ Optical Cable pre-commissioning post installation<\/span><\/li>\n<li><span style=\"color: #000000;\">Perform as-built ROV video surveys<\/span><\/li>\n<\/ul>\n<p><span style=\"color: #000000;\"><strong>MY INVOLVEMENT:<\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\">I was only involve at the initial stage for this project. Mt scope of work was to come up and write up the mehtodlogy for the FSO Slough Installation and also to assist in coming up with the Pre-com methodology<\/span><\/p>\n<p><span style=\"color: #000000;\">I only stayed 2 month for this project before being ask to<\/span><\/p>\n<p><span style=\"color: #000000;\">From last what I heard, the project was successfully executed. Well Done Guys.<\/span><\/p>\n<p><span style=\"color: #000000;\"><strong><span style=\"text-decoration: underline;\">INTRODUCTION<\/span><\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\">Mellitah Oil and Gas B.V. (hereafter referred to as COMPANY) has developed plans to replace the existing Floating Storage Offloading (FSO) \u201cSLOUG\u201d with a new built vessel at its offshore field \u201cBOURI\u201d. The field is located 120km North West of Tripoli, Libya and consist of a central processing platform DP4 and a satellite platform DP3 in water depths of 170m. STX Offshore &amp; Shipbuilding (hereafter referred to as CONTRACTOR) and EMAS AMC (hereafter referred to as SUB-CONTRACTOR) have been awarded a contract to provide Engineering, Procurement, Construction, Installation and Commissioning (EPCIC) of the new offshore facilities which consist of the following:-<\/span><\/p>\n<ul>\n<li><span style=\"color: #000000;\">A Single Point Mooring (SPM) system;<\/span><\/li>\n<li><span style=\"color: #000000;\">A Floating Storage and Offloading Vessel;<\/span><\/li>\n<li><span style=\"color: #000000;\">New subsea pipeline including tie-in to DP4 platform and new FSO.<\/span><\/li>\n<li><span style=\"color: #000000;\">A separate power cable from DP4 to the new FSO<\/span><\/li>\n<\/ul>\n<p><span style=\"color: #000000;\">The installation and hookup of the new FSO is scheduled to take place in the first quarter of 2015.<\/span><\/p>\n<p><span style=\"color: #000000;\"><b><u>Feasibility<\/u><\/b><strong><span style=\"text-decoration: underline;\">\u00a0Study FSO Slough Installation<\/span><\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>Mooring System Installation &amp; Pre-tensioning<\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\">This section presents the proposed installation methodology for the mooring system and includes pre-tensioning of the system prior to hook-up. The mooring chains and piles shall be installed by the Boa Sub C and pre-tensioning shall be done later by the Lewek Falcon.<\/span><\/p>\n<p><span style=\"color: #000000;\">The mooring chains and piles shall be installed in two trips, with an interim load-out after the 1st trip. Six (6) mooring chains and piles shall be installed in the 1st trip, after which the MIV shall load the remaining chain and piles from the barge on site.<\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>Vesse<\/strong><strong>l Preparations Works<\/strong><\/span><\/p>\n<ol>\n<li><span style=\"color: #000000;\">\u00a0Arrive in field. Perform field entry, DP trials and survey calibrations as required.<\/span><\/li>\n<li><span style=\"color: #000000;\">\u00a0Perform pre-lay survey of mooring chain corridors.<\/span><\/li>\n<li><span style=\"color: #000000;\">Perform pre-installation survey for PGF and pile positions.<\/span><\/li>\n<li><span style=\"color: #000000;\">All subsea assets, design locations and target boxes of the piles and chain corridors are displayed on the vessel survey navigation screens.<\/span><\/li>\n<li><span style=\"color: #000000;\">Position vessel in right location for overboarding the pile guide frame.<\/span><\/li>\n<\/ol>\n<p><span style=\"color: #000000;\"><strong>P<\/strong><strong>il<\/strong><strong>e Guide Frame (PGF) Over-boarding<\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\">Perform pre-deployment checks of the PGF:-<\/span><\/p>\n<ul>\n<li><span style=\"color: #000000;\">Ensure transponders are fitted to the PGF and fully charged.<\/span><\/li>\n<li><span style=\"color: #000000;\">Check the bullseye and confirm steel ball is visible<\/span><\/li>\n<li><span style=\"color: #000000;\">Ensure PGF lift rigging is connected and in good condition for lifting<\/span><\/li>\n<li><span style=\"color: #000000;\">Ensure ROV docking station is in place for orientation of PGF<\/span><\/li>\n<li><span style=\"color: #000000;\">Ensure tag lines in place for overboarding<\/span><\/li>\n<\/ul>\n<ol>\n<li><span style=\"color: #000000;\">Remove seafastening for the PGF.<\/span><\/li>\n<li><span style=\"color: #000000;\">Connect PGF lift rigging to MIV main crane block<\/span><\/li>\n<li><span style=\"color: #000000;\">Confirm vessel is in position for overboarding the PGF<\/span><\/li>\n<li><span style=\"color: #000000;\">Lift \u00a0PGF \u00a0off \u00a0the \u00a0deck \u00a0of \u00a0the \u00a0MIV \u00a0and \u00a0slew \u00a0crane \u00a0as \u00a0required \u00a0to overboard PGF.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lower PGF through splash zone up to 50m below surface.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lower the PGF to 20m off seabed and all stop on crane.<\/span><\/li>\n<li><span style=\"color: #000000;\">Activate heave compensation on crane.<\/span><\/li>\n<li><span style=\"color: #000000;\">Step vessel into PGF target box location with ROV monitoring.<\/span><\/li>\n<li><span style=\"color: #000000;\">Once PGF is in target box, ROV to dock into docking frame on the PGF and orientate the PGF as required to the right orientation.<\/span><\/li>\n<li><span style=\"color: #000000;\">Once the PGF is within the required target box and within the specified heading envelope, come down on the crane gradually and land the PGF on the seabed.<\/span><\/li>\n<li><span style=\"color: #000000;\">Survey to confirm the PGF installation position and orientation. ROV to check the bullseye on the PGF as a measure of verticality.<\/span><\/li>\n<li><span style=\"color: #000000;\">Record the position, orientation and verticality of the PGF.<\/span><\/li>\n<li><span style=\"color: #000000;\">Disconnect crane from PGF rigging and recover crane to surface.<\/span><\/li>\n<\/ol>\n<p><span style=\"color: #000000;\"><strong>Mooring Pile Overboarding and Installation<\/strong><\/span><\/p>\n<ol>\n<li><span style=\"color: #000000;\">Perform pre-deployment checks for the pile and chain:-<\/span><br \/>\n<span style=\"color: #000000;\"> \u00b7 Ensure mooring chain is connected to pile padeye via special anchor shackle.<\/span><br \/>\n<span style=\"color: #000000;\"> \u00b7 One side of alternate chain links have been painted white for twist monitoring during lay (This shall be completed during load out)<\/span><br \/>\n<span style=\"color: #000000;\"> \u00b7 Confirm right chain (correct length) to be laid at pile position<\/span><\/li>\n<li><span style=\"color: #000000;\">Record \u00a0mooring \u00a0components \u00a0identification \u00a0and \u00a0take \u00a0photos \u00a0prior deployment.<\/span><\/li>\n<li><span style=\"color: #000000;\">Assemble pile hang-off pennant rigging arrangement.<\/span><\/li>\n<li><span style=\"color: #000000;\">Install pile hang-off pennant onto hang-off platform on STBD side.<\/span><\/li>\n<li><span style=\"color: #000000;\">Recover 1st chain end from the chain locker compartment.<\/span><\/li>\n<li><span style=\"color: #000000;\">Engage chain in gypsy and ensure chain is correctly seated in gypsy chain pockets.<\/span><\/li>\n<li><span style=\"color: #000000;\">Pay \u00a0out \u00a0chain \u00a0using \u00a0the \u00a0gypsy \u00a0and \u00a0with \u00a0a \u00a0suitable \u00a0deck \u00a0sheaving arrangement, use a tugger winch to pull the chain from the chain locker exit to the main deck within the reach of the aft crane.<\/span><\/li>\n<li><span style=\"color: #000000;\">Connect suitable lift rigging attached to the end link of the chain to the aft crane.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lift the end of the chain with the aft crane, slew and overboard the chain over the stern roller and pay out the chain as necessary by the gypsy.<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue paying out on the chain gypsy and have the chain over the stern roller, creating a belly underneath the MIV.<\/span><\/li>\n<li><span style=\"color: #000000;\">Once \u00a0the \u00a0belly \u00a0is \u00a0~20m \u00a0below \u00a0water \u00a0surface, \u00a0slew \u00a0the \u00a0aft \u00a0crane outboard and towards the STBD side of the vessel.<\/span><\/li>\n<li><span style=\"color: #000000;\">Bring the end of the chain inboard and connect to the pile padeye of the pile to be overboarded.\u00a0<strong>No<\/strong><strong>te: Belly of chain is still intact.<\/strong><\/span><\/li>\n<li><span style=\"color: #000000;\">Remove seafastening for pile to be overboarded.<\/span><\/li>\n<li><span style=\"color: #000000;\">Stab\u00a0 \u00a0ILT\/PUT\u00a0 \u00a0and\u00a0 \u00a0rig\u00a0 \u00a0up\u00a0 \u00a0pile\u00a0 \u00a0for\u00a0 \u00a0overboarding\u00a0 \u00a0as\u00a0 \u00a0per\u00a0 \u00a0lifting arrangement.<\/span><\/li>\n<li><span style=\"color: #000000;\">Ensure tag lines are attached to the piles for overboarding.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lift \u00a0pile \u00a0using \u00a0main \u00a0crane, \u00a0slew \u00a0outboard \u00a0towards \u00a0STBD \u00a0side \u00a0and deploy pile through splash zone.\u00a0<strong>No<\/strong><strong>te: Ensure sufficient clearance for pile overboarding between main crane and aft crane during slewing and overboarding operation. Ensure vessel position \/ pile does not induce a twist in the chain.<\/strong><\/span><\/li>\n<li><span style=\"color: #000000;\">Lower pile to approximately 25m water depth.<\/span><\/li>\n<li><span style=\"color: #000000;\">Deploy ROV to pile location.<\/span><\/li>\n<li><span style=\"color: #000000;\">Orientate pile such that up-ending sling is adjacent to the pile hang-off pennant ROV hook previously deployed.<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to connect up-ending sling into ROV hook attached to end of hang-off pennant<\/span><\/li>\n<li><span style=\"color: #000000;\">Commence lowering main crane. Such that up-ending sling starts to take weight and pile starts to upend. ROV to monitor up-ending operation.<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue lowering main crane until pile is fully upended and crane lift rigging is slack.<\/span><\/li>\n<li><span style=\"color: #000000;\">Disconnect pile overboarding rigging by ROV and recover crane to surface.<\/span><\/li>\n<li><span style=\"color: #000000;\">Install pile installation rigging onto main crane and re-deploy crane to hang-off position.<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to connect pile lift rigging to 2nd \u00a0transfer sling at pile and take up weight on crane.<\/span><\/li>\n<li><span style=\"color: #000000;\">Come \u00a0up \u00a0on \u00a0crane to take \u00a0weight \u00a0of \u00a0pile \u00a0and \u00a0disconnect \u00a0hang-off pennant by ROV.<\/span><\/li>\n<li><span style=\"color: #000000;\">Start \u00a0lowering \u00a0pile \u00a0towards \u00a0the \u00a0seabed \u00a0while \u00a0stepping \u00a0the \u00a0vessel towards the PGF position.<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue lowering until pile is approximately 5m above top of PGF.<\/span><\/li>\n<li><span style=\"color: #000000;\">Activate AHC on main crane.<\/span><\/li>\n<li><span style=\"color: #000000;\">Complete final vessel positioning above PGF and continue lowering pile towards PGF.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lower pile until the tip engages with the guide frame, continue lowering until pile guide aides engage with pile guide vanes to finally orientate pile, maintain verticality with fine positioning of crane\/vessel as required.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lower pile into seabed until full self-penetration is achieved. Estimated self-penetration of pile is 7 m.<\/span><\/li>\n<li><span style=\"color: #000000;\">Confirm pile is within installation critieria. Check bullseye reading on PGF to confirm pile landing has not upset level of PGF.<\/span><\/li>\n<li><span style=\"color: #000000;\">Disconnect ILT\/PUT from top of tile and recover back to surface.<\/span><\/li>\n<\/ol>\n<p><span style=\"color: #000000;\"><strong>P<\/strong><strong>il<\/strong><strong>e Hammer Deployment and Piling operations<\/strong><\/span><\/p>\n<ol>\n<li><span style=\"color: #000000;\">Hammer technicians to perform all pre-deployment checks according to vendor\u2019s operation manual.<\/span><\/li>\n<li><span style=\"color: #000000;\">Connect hammer lift rigging to main crane block and ensure tag lines are attached to hammer.<\/span><\/li>\n<li><span style=\"color: #000000;\">Remove all seafastenings.<\/span><\/li>\n<li><span style=\"color: #000000;\">Upend hammer with sleeve on its storage frame.\u00a0<strong>No<\/strong><strong>te: Ensure there is sufficient slack on hammer umbilical and control lines during upending.<\/strong><\/span><\/li>\n<li><span style=\"color: #000000;\">Lift hammer out of the upending frame, and slew hammer over the STBD side of the vessel. Payout umbilical and control cable as required to maintain slack.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lower hammer through the splash zone, stop lowering and function test the water level sensors.<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue lowering the hammer through the water column towards the PGF.<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to monitor catenary of hammer umbilical and control cable during deployment.<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue lowering until hammer is approximately 5m above pile.<\/span><\/li>\n<li><span style=\"color: #000000;\">Activate AHC for crane.<\/span><\/li>\n<li><span style=\"color: #000000;\">Stab pile hammer sleeve over the top of the pile.<\/span><\/li>\n<li><span style=\"color: #000000;\">Adjust \u00a0hammer \u00a0umbilical \u00a0and \u00a0control \u00a0cable \u00a0catenaries \u00a0to \u00a0provide sufficient slack during driving.<\/span><\/li>\n<li><span style=\"color: #000000;\">Position ROV to monitor pile penetration.<\/span><\/li>\n<li><span style=\"color: #000000;\">Start \u00a0pile \u00a0driving \u00a0with \u00a0a \u00a0low \u00a0blow \u00a0rate \u00a0and \u00a0energy \u00a0level; \u00a0continue monitoring pile verticality while gradually increasing the blow rate and energy level until hammer and pile are stable.<\/span><\/li>\n<li><span style=\"color: #000000;\">Set energy level according to driving conditions and continue driving in automatic position.<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to maintain visual at all times to estimate pile verticality.<\/span><\/li>\n<li><span style=\"color: #000000;\">Record a running log of all pile driving operations.<\/span><\/li>\n<li><span style=\"color: #000000;\">Slow down the driving speed as the release ring approaches 2m from top of frame sleeve.<\/span><\/li>\n<li><span style=\"color: #000000;\">When the release ring reaches 2m, stop driving and disengage the frame safety lock bars by ROV.<\/span><\/li>\n<li><span style=\"color: #000000;\">Re-start driving steadily.\u00a0<strong>No<\/strong><strong>te: Once the release ring passes the latch kick plates in the sleeve, the PGF will open up clear from pile \u2013 ROV to remain clear.<\/strong><\/span><\/li>\n<li><span style=\"color: #000000;\">Record new penetration depth for pile once PGF has opened.<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue driving operations at normal speed until target penetration depth is reached.<\/span><\/li>\n<li><span style=\"color: #000000;\">Record final penetration depth on chart and complete pile driving log.<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to carry out survey and record as-installed position of pile.<\/span><\/li>\n<li><span style=\"color: #000000;\">Come up on crane to lift hammer clear of pile top.<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue lifting hammer while paying in umbilical hoses, control cable until 50m water depth.<\/span><\/li>\n<li><span style=\"color: #000000;\">Recover hammer back on deck.<\/span><\/li>\n<\/ol>\n<p><span style=\"color: #000000;\"><strong>Mooring Leg Installation<\/strong><\/span><\/p>\n<ol>\n<li><span style=\"color: #000000;\">On completion of pile installation activities, the mooring chain can be laid along the mooring route corridor.<\/span><\/li>\n<li><span style=\"color: #000000;\">Set-up vessel on best heading for laying the mooring leg.<\/span><\/li>\n<li><span style=\"color: #000000;\">Commence paying out the chain gypsy while stepping the vessel along the lay corridor.<\/span><\/li>\n<li><span style=\"color: #000000;\">Maintain the minimum layback distance as per the chain lay tables.<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to monitor the TDP during lay and record any twists visible in the mooring chain.<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue laying the remainder of the chain along the corridor.<\/span><\/li>\n<li><span style=\"color: #000000;\">Once the end link of the chain exits the chain locker, suspend all lay operations.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lock off chain using hang-off plate below gypsy.<\/span><\/li>\n<li><span style=\"color: #000000;\">Connect chain A&amp;R rigging to the 6th link from the end of the chain.<\/span><\/li>\n<li><span style=\"color: #000000;\">Connect work winch wire to chain using suitable rigging.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lift chain end, take catenary weight with winch and withdraw chain gypsy hang-off plate.<\/span><\/li>\n<li><span style=\"color: #000000;\">Abandon chain towards seabed while stepping vessel along mooring corridor. ROV to monitor whole operation.\u00a0<strong>No<\/strong><strong>te: End of chain to be attached with subsea recovery rigging \/ Clearly mark subsea buoy with the current chain leg.<\/strong><\/span><\/li>\n<li><span style=\"color: #000000;\">Once the chain end lands on seabed, ROV to disconnect work wire from A&amp;R rigging.<\/span><\/li>\n<li><span style=\"color: #000000;\">Recover work wire back to surface.<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to take a fix at the A&amp;R connection chain link and mark chain position on the survey screen.<\/span><\/li>\n<\/ol>\n<p><span style=\"color: #000000;\"><strong>P<\/strong><strong>G<\/strong><strong>F relocation<\/strong>\u00a0<\/span><\/p>\n<ol>\n<li><span style=\"color: #000000;\">Set-up \u00a0vessel \u00a0on \u00a0best \u00a0heading \u00a0for \u00a0lifting \u00a0operations \u00a0above \u00a0PGF position.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Deploy ROV to PGF.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Deploy main crane with stinger rigging with ROV hook on the end.<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to connect PGF lift rigging to ROV hook.\u00a0<strong>No<\/strong><strong>te: The PGF will be in its \u201copen\u201d configuration, and will self-\u00a0<\/strong><strong>c<\/strong><strong>l<\/strong><strong>os<\/strong><strong>e as the lift progresses.<\/strong><\/span><\/li>\n<li><span style=\"color: #000000;\">Take \u00a0tension \u00a0in \u00a0the \u00a0PGF \u00a0lift \u00a0rigging, \u00a0maintain \u00a0tension \u00a0and \u00a0use vessel\/crane motion to break seabed suction until frame lifts off seabed.\u00a0<strong>No<\/strong><strong>te: Monitor crane hook load at all times during breakout of PGF.<\/strong><\/span><\/li>\n<li><span style=\"color: #000000;\">Continue lifting PGF until sufficient clearance off seabed is achieved (minimum 25m).\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to check PGF is fully closed and all safety lock bars are engaged.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Step vessel to next pile location at low speed and ensure clear of any\u00a0subsea assets.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to monitor PGF during vessel move.<\/span><\/li>\n<li><span style=\"color: #000000;\">Repeat the above steps until all chains 1-9 are installed and abandoned on the seabed. This includes the interim mobilization of the remaining chains and piles after the 1st trip.<\/span><\/li>\n<li><span style=\"color: #000000;\">Recover the PGF back to deck of the MIV\/barge.\u00a0<\/span><\/li>\n<\/ol>\n<p><span style=\"color: #000000;\"><strong>P<\/strong><strong>re-tensioning of Mooring Chains<\/strong>\u00a0<\/span><\/p>\n<ol>\n<li><span style=\"color: #000000;\">Prepare chain tensioning rigging on deck of Lewek Falcon. \u00a0 <\/span><\/li>\n<li><span style=\"color: #000000;\">Based \u00a0on \u00a0the \u00a0survey \u00a0system \u00a0which \u00a0indicates \u00a0the \u00a0location \u00a0of \u00a0each subsea buoy, Lewek Falcon shall approach subsea buoy for first chain to be recovered.<\/span><\/li>\n<li><span style=\"color: #000000;\">Deploy work wire with ROV hook to buoy location and ROV to connect ROV hook to recovery rigging.<\/span><\/li>\n<li><span style=\"color: #000000;\">Recover subsea buoy to deck of Lewek Falcon and continue recovering until the chain can be locked off in the karm forks.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lock the chain link using the karm forks.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Release tension on the work wire and disconnect subsea buoy rigging from chain.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue paying in on the work wire and recovering the chain once buoy rigging is disconnected.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Recover the end of the chain across the main deck to entrance of the chain locker.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Using the chain gypsy, start recovering the chain and storing them into the chain locker<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue \u00a0doing \u00a0this \u00a0until \u00a0approximately \u00a0500m \u00a0of \u00a0chain \u00a0have \u00a0been recovered on board the vessel.\u00a0<strong>No<\/strong><strong>te: The length of chain to be recovered shall depend on the\u00a0<\/strong><strong>cha<\/strong><strong>i<\/strong><strong>n\u00a0 \u00a0catenary\u00a0 \u00a0length\u00a0 \u00a0on\u00a0 \u00a0seabed\u00a0 \u00a0required\u00a0 \u00a0to\u00a0 \u00a0achieve\u00a0 \u00a0the pretension value.<\/strong><\/span><\/li>\n<li><span style=\"color: #000000;\">Lock chain link in karm fork. <\/span><\/li>\n<li><span style=\"color: #000000;\">Connect chain pre-tensioning rigging with one end to chain link after the karm fork and the other end to the work wire.<\/span><\/li>\n<li><span style=\"color: #000000;\">Check and confirm load cell is working condition.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Position vessel for chain tensioning operations.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Take up tension \u00a0on the \u00a0work \u00a0wire \u00a0and \u00a0transfer\u00a0 full \u00a0chain \u00a0catenary weight on karm fork to work wire.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Release and lower down karm fork. <\/span><\/li>\n<li><span style=\"color: #000000;\">Start pre-tensioning of the mooring chain, gradually increasing vessel thrust until the required pre-tension value is achieved. (Current estimate is <strong>275te<\/strong>)<\/span><\/li>\n<li><span style=\"color: #000000;\">Hold the intended tension value for 15 minutes.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Obtain approval and sign-off from the Client\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Gradually reduce the vessel thrust and step the vessel back to slack off the chain catenary.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lock chain link off in karm fork and disconnect chain tensioning rigging from work wire.\u00a0\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Take up tension with the chain gypsy and lower karm fork.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Relay chain along mooring corridor towards turret center. <\/span><\/li>\n<li><span style=\"color: #000000;\">Once the end link of the chain exits the chain locker, suspend all lay operations.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lock off chain using hang-off plate below gypsy.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Connect chain A&amp;R rigging to the 6th link from the end of the chain.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Connect work winch wire to chain using suitable rigging.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Lift chain end, take catenary weight with winch and withdraw chain gypsy hang-off plate.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Abandon chain towards seabed while stepping vessel along mooring corridor. ROV to monitor whole operation.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Once the chain end lands on seabed, ROV to disconnect work wire from A&amp;R rigging.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Recover work wire back to surface. <\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to take a fix at the A&amp;R connection chain link and mark chain position on the survey screen.\u00a0<strong>No<\/strong><strong>te: Chain should be peeled back and end of chain attached with\u00a0<\/strong><strong>recovery rigging for hook-up to FSO.<\/strong><\/span><\/li>\n<\/ol>\n<p><span style=\"color: #000000;\"><strong>Mooring System Hook-up to FSO and Final tensioning<\/strong><\/span><\/p>\n<p><span style=\"color: #000000;\">This section presents the method statement for hooking up the mooring chains to the FSO and performing the final tension required for the mooring chains. This activity shall only be performed upon the arrival of the FSO in field.<\/span><\/p>\n<p><span style=\"color: #000000;\"><strong>Vesse<\/strong><strong>l Preparations<\/strong>\u00a0<\/span><\/p>\n<ol>\n<li><span style=\"color: #000000;\">Ensure all preparatory works on FSO for chain pull-in performed:<\/span><br \/>\n<span style=\"color: #000000;\">\u00b7 Survey system on FSO tested and functional<\/span><br \/>\n<span style=\"color: #000000;\">\u00b7 Pull-in routing arrangement from pull-in winch down to chain stopper in order<\/span><br \/>\n<span style=\"color: #000000;\">\u00b7 Verify chain stopper\/chain table orientation for first chain hook-up based on FSO heading<\/span><br \/>\n<span style=\"color: #000000;\">\u00b7 Pull-in winch function tested<\/span><br \/>\n<span style=\"color: #000000;\">\u00b7 Inspect messenger lines moused through chain stopper<\/span><\/li>\n<li><span style=\"color: #000000;\">FSO to arrive in field. Three (3) heading control and positioning tugs shall be connected to the FSO for heading control of the FSO during the mooring hook-up.<\/span><\/li>\n<\/ol>\n<p><span style=\"color: #000000;\"><strong>Reco<\/strong><strong>v<\/strong><strong>e<\/strong><strong>r<\/strong><strong>y of Mooring Chain<\/strong>\u00a0<\/span><\/p>\n<ol>\n<li><span style=\"color: #000000;\">Lewek Falcon to position over the end of the first mooring chain to be recovered as indicated on survey navigation screen.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Deploy ROV and locate subsea recovery rigging attached to end of chain.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Deploy crane whip line with ROV hook attached to end of crane\u00a0stinger.<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to connect ROV hook to subsea recovery rigging.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Recover chain end over stern roller of Lewek Falcon, stepping vessel back along lay path during recovery.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Lock off chain link in karm fork and disconnect crane wire and recovery rigging.\u00a0<\/span><\/li>\n<\/ol>\n<p><span style=\"color: #000000;\"><strong>I<\/strong><strong>n<\/strong><strong>i<\/strong><strong>tial Pull-in of Mooring Chain<\/strong>\u00a0<\/span><\/p>\n<ol>\n<li><span style=\"color: #000000;\">Stabilise FSO with the assistance of the heading control tugs and survey.<\/span><\/li>\n<li><span style=\"color: #000000;\">Step Lewek Falcon to within 20m of turret centre. <\/span><\/li>\n<li><span style=\"color: #000000;\">Pay out and deploy FSO pull-in winch wire and messenger line until end is ~ 50m below water line.\u00a0<strong>No<\/strong><strong>te: FSO winch wire has been previously routed from pull- in winch through chain stoppers.<\/strong><\/span><\/li>\n<li><span style=\"color: #000000;\">Recover messenger line and pull-in winch wire to deck of Lewek Falcon with the assistance of crane and ROV.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Attach and connect end of pull-in wire to mooring chain end link. <\/span><\/li>\n<li><span style=\"color: #000000;\">Connect crane\/work winch to sacrificial sling connected to chain link 5m away from end link and take up tension on crane.<\/span><\/li>\n<li><span style=\"color: #000000;\">Lower\u00a0 karm fork\u00a0 and overboard chain over\u00a0 stern roller\u00a0 using main crane.<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue lowering chain with crane and slowly cross haul to FSO with ROV monitoring chain catenary.<\/span><\/li>\n<li><span style=\"color: #000000;\">Commence hauling in on FSO pull-in winch wire and \u201csucking\u201d in excess chain length while Falcon\u2019s crane is still taking on the chain catenary\u2019s weight.<\/span><\/li>\n<li><span style=\"color: #000000;\">ROV to cut sacrificial sling at chain link once chain is almost directly below FSO chain table. Recover work wire to deck.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Continue \u00a0pulling \u00a0in \u00a0chain \u00a0until \u00a02nd\u00a0 \u00a0link \u00a0of \u00a0mooring \u00a0chain \u00a0is engaged in chain stopper.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Deploy air divers to disconnect pull-in winch wire from chain at chain table. <\/span><\/li>\n<li><span style=\"color: #000000;\">Reposition FSO and Lewek Falcon as required and re-configure chain pull-in arrangement for subsequent chain pull-in for remaining chains.\u00a0<strong>No<\/strong><strong>te: Centre chain for each cluster to be pull-in first. Once the 3 chains have been pulled in, the two bow tugs can be disconnected and the FSO heading maintained by the stern tug<\/strong>.<\/span><br \/>\n<span style=\"color: #000000;\">\u00b7 Scuba Replacement needs to be evaluated to complete this activity.<\/span><\/li>\n<li><span style=\"color: #000000;\">Repeat Steps 1-13 for remaining chain legs in sequence.\u00a0<\/span><\/li>\n<\/ol>\n<p><span style=\"color: #000000;\"><strong>Cha<\/strong><strong>i<\/strong><strong>n Tensioning<\/strong>\u00a0<\/span><\/p>\n<ol>\n<li><span style=\"color: #000000;\">Once \u00a0all \u00a09 \u00a0chains \u00a0have \u00a0been \u00a0pulled \u00a0in \u00a0and \u00a0locked \u00a0in \u00a0chain\u00a0stoppers, system is ready for final tensioning.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Route pull-in winch wire through upper cantilever penetration and lower to chain table through the mooring wheel.<\/span><\/li>\n<li><span style=\"color: #000000;\">Deploy air divers to work on chain table top.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Connect pull-in winch wire to chain end link.<\/span><\/li>\n<li><span style=\"color: #000000;\">Commence hauling in on winch and hoist chain out of chain stopper allowing chain clacker to open.<\/span><\/li>\n<li><span style=\"color: #000000;\">\u00a0Continue hauling in on winch and pulling in chain until maximum stroke is achieved or target link is reached.\u00a0<strong>No<\/strong><strong>te: This operation may be performed over several strokes of pull-in. Final link shall be identified and confirmed by attending engineer from LMC.<\/strong><\/span><\/li>\n<li><span style=\"color: #000000;\">Once target link is pulled through and locked in chain stopper, slack pull-in winch wire and lower chain onto chain table.\u00a0<\/span><\/li>\n<li><span style=\"color: #000000;\">Air divers to cut link above locking link using broco torch. <\/span><\/li>\n<li><span style=\"color: #000000;\">Once the chain link is cut, the cut length of chain shall be cross hauled to Lewek Falcon for disposal.<\/span><\/li>\n<li><span style=\"color: #000000;\">Repeat Steps 2-9 for remaining chain legs until all 9 chains have been tensioned to desired value.<\/span><\/li>\n<li><span style=\"color: #000000;\">The position of the turret shall be checked and compared with predicted values using transponder\/transducer references. Angles of each chain shall also be checked against design values. In addition, diver to check using chain angle measurement tool.<\/span><\/li>\n<\/ol>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>&nbsp; COMPANY: EMAS-AMC PROJECT TITLE: GAZA FSO (Slough Replacement) CLIENT:\u00a0STX Offshore LOCATION:\u00a0Libya YEAR: 2014 VESSEL: Subsea Construction Vessel Lewek Connector SCOPE OF WORK: Project Management and engineering Procurement and fabrication &hellip; <a class=\"readmore\" href=\"http:\/\/alfanso10.com\/?p=874\">Continue Reading \u2192<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[25],"tags":[],"_links":{"self":[{"href":"http:\/\/alfanso10.com\/index.php?rest_route=\/wp\/v2\/posts\/874"}],"collection":[{"href":"http:\/\/alfanso10.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/alfanso10.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/alfanso10.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/alfanso10.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=874"}],"version-history":[{"count":8,"href":"http:\/\/alfanso10.com\/index.php?rest_route=\/wp\/v2\/posts\/874\/revisions"}],"predecessor-version":[{"id":1452,"href":"http:\/\/alfanso10.com\/index.php?rest_route=\/wp\/v2\/posts\/874\/revisions\/1452"}],"wp:attachment":[{"href":"http:\/\/alfanso10.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=874"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/alfanso10.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=874"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/alfanso10.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=874"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}