Offshore platform slot recovery process
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Transcript of Offshore platform slot recovery process
Asset Life Extension Process Platform Slot Recovery
GULF OF SUEZ PETROLEUM Co. GUPCO
D R I L L I N G E N G I N E E R
KAMEL ELSAYED
Slot recovery on J58-82 Site preparation for SB293-4 ERD WELL
ST BAHARI-1 TEAM
As operators cope with
maturing fields and
challenging market
conditions, it has become
increasingly important to
manage and extend the life
of assets
CONTENTS
STAGE I : SECURING THE STRING FOR CUTTING
STAGE II : MULTI STRING CUTTER
STAGE III : PULL THE CUT-OFF STRING
STAGE IV : CUTTING STRING INTO PIECES
STAGE V : P/U DCS
Before start cutting the multi-string conductor,
we had to apply tension on the string so it
would come out easily when cutting is finished.
Applying tension would also make cutting faster.
We did that using CTU, C-plate and a spider
elevator
1 1
• A conductor tensioner unit is installed on an offshore jackup rig to apply upward tension on the conductor.
• A Conductor Tensioning System consists of an elevated tensioning ring pinned to and supported by hydraulic tensioning cylinders, each of which are interconnected to a compensated hydraulic circuit employing bladder type accumulators.
• When the cylinders are hydraulically extended to their mid-stroke, the tensioning ring exerts a balanced upward pressure against a collar fitted around the conductor, thereby imposing vertical tension on the conductor string.
FIRST … WHAT IS A CTU ?!
CONDUCTOR TENSIONER UNIT
TYPICAL SPECIFICATION Tensioning capacity: 400 TON Max. conductor diameter: 36” (Adaptors available for smaller conductor diameters) Hydraulic cylinders: 8-Off (4-Off per half) Cylinder stroke: 610mm Accumulators: Up to 11-Off bladder type Nitrogen filled Mode of travel: Slot and claw type Skidding mechanism for travel across CTP structure
LARGE SKID-MOUNTED SPLIT CTU
CTU, inside
Cantilever
Conductor Tensioning Unit
WHAT IS A CTU ?!
STAGE #1: SECURING THE STRING FOR CUTTING
Removed the THS, then install 13-3/8” pulling tool onto the Braden head
CTU
C-Plate
Spider
Elevator
13-3/8” CSG
Pulling tool
STAGE #1: SECURING THE STRING FOR CUTTING
The C-plate supports the Spider elevator, which clamps on the pulling tool. Then the CTU pistons can be extended to apply the desired amount of pulling force.
CTU Hydraulic
Pistons
Now that we have the enough tension on the
string to be cut, cutting operation can
commence.
2 2
STAGE #2: MULTI STRING CUTTER
STAGE #2: MULTI STRING CUTTER
MSC knives protruding from the 24” conductor due to eccentricity of casing strings
MSC got stuck while trying to cut the rest of the 24” Conductor (due to eccentricity)
After many trials of rotating and applying overpull, we were successful to pull the
MSC out with all knives recovered
Multi-String Cutter Note
STAGE #2: MULTI STRING CUTTER
Damaged knives after POH … and knives were stuck in place and back-loaded as it is .
We think that knives got bent laterally due to high torque applied to them … not because of the over pull or slack
As a result we couldn’t get the knives back in place and that why we had to put
extra pull to retract them.
The sides of the knives had peeled off while trying to retract knives into place.
Multi-String Cutter Note
STAGE #2: MULTI STRING CUTTER
The sides of the knives had peeled off while trying to retract knives into place.
STAGE #2: MULTI STRING CUTTER
We ran in hole again with new set of knives and could successfully cut thru.
CSG Stump Eccentricity of CSG strings is very clear
Cut-off string
Now we can recover the cut-off string to the
surface, but first we have to secure it.
3
STAGE #3: Pull the cut-off string
1- On the Production deck, Below the braden head, Cut window thru the 3 CSG strings and install a pin as a securing pin (not to allow any string to slip off) and as a lifting pin as well.
STAGE #3: PULL THE CUT-OFF STRING
2- Remove the Spider Elevator and C-plate 3- Pull the string till the Braden head is above the rig floor
4
Now we have to cut the string into smaller
pieces that can be handled and transported
We’re going do that using:
1- BORAIS Dual pin drill
&
2- BORAIS Guillotine pipe saw
• Dual Pin Drill with hydraulically-powered twin opposed drills are used to prepare cut sections of casing for securing and rigging.
• Dual Pin Drill incorporates two opposed drills on a mounting frame for drilling precisely aligned holes through which bolts or pins can be inserted to secure multiple-layered casings. Holes up to 4” can be drilled.
DUAL PIN DRILL Quick Note
BORAIS DUAL HOLE DRILLING MACHINE
BORAIS DUAL HOLE DRILLING MACHINE IN ACTION
STAGE #4: CUTTING STRING INTO PIECES
Carbide inserts
Cut-off pieces due to hole drilling
24” 13-3/8” 9-5/8”
• Designed to cold cut 16” to 32” pipe of all materials, as well as solids , and multi-stranded casing strings, can work in sub-sea conditions.
• It has Auto-clamp & Auto-feed features.
• A 16” diameter 3/4” wall steel pipe is cut in only 24 minutes. • A 32” diameter multi-stranded casing string is cut in about 48 minutes.
GUILLOTINE PIPE SAW Quick Note
BORAIS GUILLOTINE PIPE SAW
STAGE #4: CUTTING STRING INTO PIECES
Cut-off the first joint by BORAIS Guillotine pipe saw, and L/D on cantilever
STAGE #4: CUTTING STRING INTO PIECES
Securing Pins … is inserted into the drilled hole to prevent any of the casing string of slipping off. It’s also secured by welding and wedges preparing for backload
5
P/U DCS parts and weld it on rig floor
BLIND BTM WITH SPIKES
DCS PART #1
DCS PART #2
XLF BOX THREAD
2 x 30” XLF CONDUCTOR JOINTS
XO 30” XLF PIN x 4-1/2” IF BOX
XO 4-1/2” IF PIN x 5-7/8” VX-57 BOX
5-7/8” VX-57 DRILL PIPES
ALL WELDED
STAGE #5: P/U DCS
DCS ASSEMBLY
STAGE #5: STAGE #5: P/U DCS
DCS part #1
STAGE #5: P/U DCS
Blind end with spikes that will grip into sea bed and prevent DCS movement with sea current
6
WAIT ON WEATHER TO RUN WITH ROV TO
ENSURE AREA AROUND OLD CASING STUMP
IS CLEAR FROM ANY DEBRIS
WAIT ON WEATHER TO RUN WITH DCS
Production deck
Cellar deck
After Running with the DCS, orienting it in the new well direction, it
should be secured to the platform by clamps to the
cellar deck and the production deck, then cold-cut the DCS just above the production
deck
Later after the rig leaves the platform, other
clamps can be installed on the subsea bracings.
Forward Plan
KAMEL ELSAYED DRILLING ENGINEER
BAHARI-1 RIG TEAM
0122 910 2341
THANKS FOR YOUR TIME