The shore pull method will be performed to initiate pipelaying. The shore approach procedure for PL1 &
PL3 is described in BRZ-GX-O-PL-0522. In short, HD-423 stern will be located at KP 87.030 for PL1 and KP 79.598 for PL3, approximately 1,700m from the LTE, and start welding the pipe. The welded pipeline will be pulled by two linear winches located in onshore. When the pulling head of 32” pipeline arrives at LTE, the pulling head will be hold by onshore padeye. After confirmation of securing the pulling head, the normal laying will be started along the designed route. (Please refer BRZ-GX-O-PL-0522 Shore Approach Procedure )
5.2 PIPELAYING
HD-423 will initiate PL3 shore pulling and proceed about 3km laying and down it on the seabed. And HD-423 will return to the initiation point of PL1. After PL1 initiation, HD-423 will lay the all PL1 line section. PL-3 will be laid after PL1.
5.2.1 Laying Sequence (Only for Information)
Seq. Operation KP WD (m) Description
1 PL3 Laying start 79.597 8 Shore Pull Operation, Laying Start with 4.5”
MEG PB Line
2 PL3 Laydown 76.597 13 Temporary laydown for PL1 shore pull operation
Return to Shore pull location
3 PL1 Laying start 88.734 8 Shore Pull Operation
Return to PL3 laydown location
7 PL3 Recovery 76.597 13 Recovery PL3 and Laying
DOCUMENT TITLE
PL1 & PL3 PIPELINE INSTALLATION PROCEDURE
HHI STD FORMAT: BRZ-GX-P-O-PL-0503 PL1 & PL3 PIPELINE INSTALLATION PROCEDURE 5.2.2 The approved route centreline
During normal pipeline laying operations the actual pipeline position shall be within ±10m of the approved route centreline.
BRZ-PL1
Refer to Pipeline Alignment Drawing for 32” BRZ-PL1 Pipeline from WHP-1 to LTE BRZ-W1XP-D-PL-0501 ( Total 36 sheets)
BRZ-PL3
Refer to Pipeline Alignment Drawing for 32” BRZ-PL1 Pipeline from WHP-3 to LTE BRZ-W3XP-D-PL-0501 ( Total 33 sheets)
5.2.3 Tension Scheme Table
The Tensioner- tension shall be controlled the below table as per the WD and CC th’k.
Refer to the BRZ-GX-O-PL-0507 PL1 & PL3 Pipeline Field Data Book.
5.2.4 Pipelaying at Pipeline/Cable Crossing location
The crossing supports shall be installed before laying start as per BRZ-GX-O-PL-0523, Pipeline support installation procedure. When HD-423 approaches to the pre-installed support location, ROV will be deployed from ROV vessel to check the support location and condition. After confirming the locations, HD-423 will keep the heading of the barge and ROV will keep monitoring the pipeline until the Pipeline touches on the supports.
5.2.5 Pipeline Laydown and Termination
As HD-423 approaches to the pipe laydown/termination area, the surveyors and onboard personnel will begin to monitor and calculate the remained length of pipe, considering the gain length of Pipeline.
Laydown/Termination Sequence
1. Termination case: confirm the remaining length of pipeline for the termination point by surveyor.
2. Remove buckle detector and other equipment from pipeline 3. Weld Termination Head on pipeline
4. Connect intermediate Termination Wire to Termination Head
5. Connect A&R cable to intermediate Termination Wire and transfer load to A&R"
Once all the tension in the A&R winch wire is 0, diver will disconnect the A&R wire from the intermediate wire, and then connect marker buoy. Diver(or ROV) will checks to confirm position of termination head by using USBL beacon.
HHI STD FORMAT: BRZ-GX-P-O-PL-0503 PL1 & PL3 PIPELINE INSTALLATION PROCEDURE
5.3 PIGGYBACK PIPELINE INSTALLATION PROCEDURE
5.3.1 Deck Preparation Works
Prior to commencement of pipe laying, deck area of pipe laying barge should be prepared for the safe and appropriate installation of 4” MEG pipelines.
1) The required preparation work at the deck area is as follows 2) Arrange pipe storage racks and pipe preparation work area 3) Install pipeline guide rollers and supports
4) Install welding / NDT station
5) This station will be installed near the X-ray cabin.
6) Install field joint coating and repair station
7) Install clamping station and electrical connection station
5.3.2 Piggyback Pipeline Initiation
1) The end of the piggyback pipe will be welded to the pulling head.
2) The pulling head will be connected to the 1/2” wire. And 1/2” wire will be connected to the padeye on the mainline pulling head to be secured.
From BAZ-Q5B0-PL-1331, 32” details of pulling head
3) Piggyback pipeline will be bundled with main pipeline by using spacer block.
4) Piggyback pipelines will be installed with main pipelines during normal laying. The spacer block will be installed as per the designed spacing and near of the piggyback pulling head.
5) Anodes for piggyback pipeline will be Thermit welded to the piggyback pipeline.
5.3.3 Installation Procedure
Duplicated parts with main pipeline installation procedure are not described in this procedure. Following step by step description concerns the general procedure for installation of 4” MEG pipeline.
HG-228 (19.1mm) SPACER BLOCK
DOCUMENT TITLE
PL1 & PL3 PIPELINE INSTALLATION PROCEDURE
HHI STD FORMAT: BRZ-GX-P-O-PL-0503 PL1 & PL3 PIPELINE INSTALLATION PROCEDURE Transportation & Handling of 3.5 & 4.5” MEG pipes
On arrival of the pipe transportation barge in the field, a deck crane will begin offloading the pipe in the order as required for normal laying. The pipe will be handled with wire slings wrapped around by rubber.
The pipe will be stored in the laybarge storage racks until needed. After storage of pipes, all pipes will be
1) Material inspection and Documentation including MPI 2) Bevels and cleaning pipes
3) Pipeline alignment and fit-up
4) Pipes are transferred to simple supports guide rollers to fit-up the pipes.
5) Field Welding
6) Welding of pipe joints shall be in accordance with client specification and company approved WPS.
In addition, pipe joint numbers will be painted onto the outside surface.
7) Field joints shall be tested in accordance with company approved NDT procedure.
8) Field joints shall be coated in accordance with company approved field joint coating procedure.
9) Clamp pipe and electrical connection.
10) In this stage, 3.5 & 4.5” lines will be clamped to 32” main line according to the company approved clamping system.
5.3.4 Piggyback Pipeline Termination
1) When the pipeline termination area is approached, the piggyback pipeline termination operation is also prepared.
2) Once the main pipeline pulling head is attached to the end of pipeline and A&R winch wire is connected to the pulling head, the termination operation will be commenced.
3) The piggyback pipeline termination head will be connected to the main pipeline termination head by using 1/2” wire and turn buckle. And the spacer block will be installed as per the designed spacing and near of the piggyback pulling head.
4) Piggyback pipeline termination operation will be done with main pipeline termination operation.
HHI STD FORMAT: BRZ-GX-P-O-PL-0503 PL1 & PL3 PIPELINE INSTALLATION PROCEDURE
5.4 LAYING WITH BAR- TEE OR FLANGE JOINT
Bar-tee to connect to 24” lines and the flange joints of the Dummy spools shall be laid with the pipeline.
HD-423 has 3 tensioners (3 x 150 Kips).
For the layout details, refer to drawing No. BRZ-GX-D-PL-0551, 0555&0557 and BRZ-W21IP-D-PL-0510 andBRZ-W23IP-D-PL-BRZ-W21IP-D-PL-0510 .
2) Pipeline Reference Point
Location Easting (m) Northing (m) KP WD, LAT (m) TEE TIE-IN(BRZ-PL12) 589,379.18 2,925,453.18 16.671 48.0 SPOOL TIE-IN(BRZ-PL12) 589,382.28 2,925,454.03 16.677 48.0 TEE TIE-IN(BRZ-PL32 589,222.60 2,924,755.05 9.394 47.0 SPOOL TIE-IN(BRZ-PL32 589,225.13 2,924,753.07 9.390 47.0
BRZ-WYE1 (Dummy) Refer to Drawing BRZ-GX-O-PL-0555 Rev.1 BRZ-WYE3
(Dummy Spool) Refer to Drawing BRZ-GX-O-PL-0557 Rev.1
LTE at BRZ-PL1 551,567.74 2,869,713.13 88.734 +2.0 LTE at BRZ-PL3 551,571.27 2,869,711.25 81.309 +2.0
Bar-tee/ flange will be welded in the welding stations and the tensioner will be opened when the bar-tee or flange joint arrive at the tensioner. During passing the tensioner, the others (2 tensioners) will maintain the below required tension. And the flanges to be connected to 24” intrafield pipeline will be blinded by a temporary blind flange. The detail operation scheme refer to the drawing No. BRZ-Q5B0-PL-1542 &3 and the operation tensions in PL1&PL3 Pipeline Field Data Book (BRZ-GX-O-PL-0507) are simplified for the easy operation.
The piggyback line to be connected with interfiled line will be terminated as BAZ-Q5B0-PL-1331 in section 7.2.2.
DOCUMENT TITLE
PL1 & PL3 PIPELINE INSTALLATION PROCEDURE
HHI STD FORMAT: BRZ-GX-P-O-PL-0503 PL1 & PL3 PIPELINE INSTALLATION PROCEDURE
6.0 CONTINGENCY PROCEDURE
This section details the various contingency and emergency response procedures.
6.1 ABANDONMENT
Temporary abandonment of pipelay operations may occur for a number of reasons; however equipment failure and weather are the two most likely reasons to force a temporary abandonment. HD-423 Superintendent will assess the situation and determine if abandonment is needed. If conditions or the situation allow, slow lay of the pipe will continue as long as viewed prudent by the HD-423 superintendent to do so. Company representative will be notified of any changes in the pipeline production or pipeline.
When weather conditions are such that the barge or support vessels must cease operation, the pipeline will be temporarily capped and placed on the seabed. This also applies when the weather forecast indicates extreme weather conditions which would require the lay spread to depart location or otherwise abandon normal operations.
In this case, the barge will lay out from under the pipeline by attaching an abandonment head to the pipeline. All internal equipment including the buckle detector will be removed from the pipeline and the head will be welded to the pipeline in the bead stall. The termination head will then be shackled to the A&R winch wire.
Excess slack will be taken out of the A&R winch wire. The barge will then begin moving forward as the tension is gradually transferred from the tensioner to the A&R winch wire. Lay tension will be maintained throughout the procedure. The pipe-support of stinger will remain at the required depth until the abandonment head has passed.
The length of wire paid out will be monitored and checked against the engineering calculations. The barge will continue to move forward until the recommended length of wire has been paid out. The barge will then remain stationary while excess wire is spooled off of the A&R winch. The survey team will record the coordinates of the end of the pipeline for future recovery.
If the barge is to remain on location, the wire will remain connected to the abandonment head and to the barge. The excess slack will be required to ensure that the movement of the barge due to sea state is not transferred to the pipeline on bottom via the wire.
If the barge will be required to abandon the location, the A/R winch wire will be paid off from the drum. A marker buoy will be attached to the end of the A/R winch wire for retrieval by the barge at a later time.
As an alternate, the pipeline may be laid on seabed and left without a buoy for recovery by the barge using divers or ROV at a later date.
Step By Step Procedure for Abandonment
If, for weather forecast reasons, the decision to abandon the pipe is taken by the superintendent of the barge, steps are as follows;
1) Check and if necessary re-position anchor pattern for barge moving without anchor handling during
HHI STD FORMAT: BRZ-GX-P-O-PL-0503 PL1 & PL3 PIPELINE INSTALLATION PROCEDURE abandonment steps.
2) Finish all welds.
3) Recover line-up internal clamp and Buckle detector.
4) Weld the abandonment head, and NDT will be carried out. And the piggyback pipeline will be cut off and supported to keep the gap for pulling head welding operation.(If required, the piggyback spacer block behind the pulling head location will be installed after welding of pulling head to keep the space for welding of piggyback pipe pulling head.)
5) Connect the A/R winch wire and spool the slack.
6) Transfer the tension from tensioner to A/R winch.
7) Once tension is transferred, fully open the tracks of tensioner to pass abandonment head.
8) Move the barge ahead until the abandonment head is reached to the last station of the barge.
9) The piggyback pipeline will be cut off and supported to keep the gap for pulling head welding operation.(If required, the piggyback spacer block behind the pulling head location will be installed after welding of pulling head to keep the space for welding of piggyback pipe pulling head)
10) It is recommended to keep the stinger in a median position while the abandonment head moves from the laying ramp to the last roller of the stinger.
11) When the abandonment head leaves the barge, a pendant rope with a marked buoy is attached to the abandonment head, and a mark is painted on the A/R winch wire at a distance equal to stinger length.
12) As soon as the abandonment head leaves the stern of barge, start to adjust the stinger in a proper position according to the results of stress analysis.
13) As soon as the abandonment head has left the stinger, stop the stinger operation and move the barge ahead a predetermined distance as per the calculation for abandonment.
14) Pay out A/R winch wire by decreasing the tension of A&R winch until the pipe touches down on the seabed. Then the wire is slacked and kept on board or released. If released, the wire is lifted with a pendant buoy.
15) In all cases, the plotting of the barge route will be precisely made, in particular when the head comes at the stern of barge.
16) If abandonment is required, according to the decision of the Barge superintendent, the stinger will be disconnected or not.
6.2 RECOVERY
When weather or other conditions are better, the barge will prepare to recover the pipeline from the seabed. For this procedure, the barge will be positioned over the abandonment location in the correct lay orientation. The marker buoy on the A/R winch wire will be recovered to the barge.
Step By Step Procedure for Recovery
1) The A/R winch wire will be passed through the stinger, up the pipe alley and connected to the A/R
DOCUMENT TITLE
PL1 & PL3 PIPELINE INSTALLATION PROCEDURE
HHI STD FORMAT: BRZ-GX-P-O-PL-0503 PL1 & PL3 PIPELINE INSTALLATION PROCEDURE winch. The barge will now be moved ahead the minimum distance.
2) The barge will remain stationary and begin spooling in the A/R winch wire. As the wire tension is set up the required lay tension, the barge will begin slowly back under the end of the pipeline while maintaining this required tension.
3) The barge will continue back under the pipeline until the end of the pipeline is past the tensioners.
4) At this point, the tension will be transferred from the A&R winch to the tensioners. Once all the tension is transferred from A&R winch to tensioners. When all the tension in A&R winch is transferred to Tensioner, A&R winch wire will be disconnected from A/R head and A/R head will be cut from main pipeline. The next joint of pipe will be ready to be welded.
5) If there is any piggyback pipeline, the A/R head of piggyback pipeline will be disconnected from A/R head of main pipeline. And then the A/R head will be removed from pipeline.
6) Normal operations will commence at this time.
Dry Buckle
The location of the buckle and the extent of damage will be determined. The buckle will be surveyed by ROV or Diver and a conclusion will be made as to whether the buckled area can be recovered to the barge.
If the buckle will pass through the pipe-support and onto the barge, the barge will begin back under the pipeline in the reverse process of laying pipe.
As the pipe joints come into the bead stall, they will be cut from the pipeline and set aside for re-bevelling. As the buckled pipeline arrives in the line-up station of lay ramp, it will be cut out. The barge will then begin stalking on the pipe joints and normal lay will resume.
If the buckle could not be passed through the pipe-support or recovered to the barge, the abandonment head will be welded on the end of the pipeline. The pipeline will be laid down to the seabed as per the termination procedures.
The barge will lift the pipeline alongside the port side by using the davits or by using a single point pickup if possible. The buckle will be cut out and the recovery head will be welded on the pipeline. And then the pipeline will then be placed on seabed and recovered as per the recovery procedures. Once on the barge, normal pipelay will resume.
Wet Buckle
The location of the buckle and the extent of damage will be determined. In case, the buckle or damage has allowed water to enter the pipeline, the pipeline will be laid on the seabed as per the abandonment procedures. The buckle will be surveyed by ROV until it is determined that pipeline is fully flooded. Only then can divers begin to work near the pipeline.
Divers will cut the pipeline at the damaged area. Divers will then insert pig stopper bars in the cut end of the pipeline. Pipeline shall be air pumped in the end of the pipeline (shore side or start pulling head location) so as to dewatering pig inserted in initiation head can dewater from start point to the damaged
HHI STD FORMAT: BRZ-GX-P-O-PL-0503 PL1 & PL3 PIPELINE INSTALLATION PROCEDURE area.
The pipeline will then be recovered to the barge as per the recovery procedure while pressurizing until the buckled joint comes up to the surface.
Failure of Tensioner System
The tensioner will be checked and monitored regularly. However, tensioners have their own shut down system for emergency case. Therefore if there is any unexpected situation occurred, tension will can be kept until the tensioner is fixed.
If the situation requires that the tension on the tensioner needs to be released from the pipe, the A/R head will be attached and connected to the A/R winch wire.
The tension will be transferred to the A/R winch and then the tensioner release the tension and then to be fixed.
Failure of Anchors and Anchor Lines
HD-423 has 10 anchoring system, and for pipelaying operation only 8 anchor systems will be used.
Therefore if there is any failure of anchor lines and mooring winch, other mooring winch will be used.
However, once if any failure of anchoring system is found, the pipelaying operation will be stopped.
The detail procedure for anchor winch trouble and anchor line failure will be described in the Anchor Handling Procedure.
Breakdown of positioning system
Once the positioning system is broken down, the laying operation will be stopped and then be waited until it is fixed.
Piggyback Pipeline and Cable Contingency Procedure Piggyback Pipeline Contingency Procedure
In case temporary abandonment is required during pipelaying operation piggyback pipeline will be also abandoned with following sequence.
While the A/R head is welded in the line-up station, the piggyback pipeline will be cut, and temporary A/R head will be welded and bundled as the Tee joint case in BAZ-Q5B0-PL-1331 in section 7.2.2.
While the A/R head is welded in the line-up station, the piggyback pipeline will be cut, and temporary A/R head will be welded and bundled as the Tee joint case in BAZ-Q5B0-PL-1331 in section 7.2.2.