Upload
trie-mardianto
View
12
Download
2
Embed Size (px)
DESCRIPTION
ITS Paper 31206 4306100087 Presentation
Citation preview
ANALISA TEGANGAN DINAMIS FLEXIBLE RISER AKIBATMOTION FPSO SAAT KONDISI FULLY LOADED DAN
BALLAST
Oleh :Moh. Sufyan Hadi Wijaya
(4306.100.087)
Dosen Pembimbing :Ir. Imam Rochani, M.Sc.
nip. 195610051984031004Ir. Handayanu, M.Sc., Ph.D.Nip. 196307281988031001
JURUSAN TEKNIK KELAUTANFAKULTAS TEKNOLOGI KELAUTAN
INSTITUT TEKNOLOGI SEPULUH NOPEMBERSURABAYA
LATAR BELAKANG
Metode produksi menggunakan bangunan terpancang mulaidigantikan dengan bangunan terapung (floating).
Flexible riser menjadi salah satu solusi nyata untukmengahadapi tantangan semakin dalamnya daerah operasi.
Flexible riser merupakan salah satu komponen strukturbangunan lepas pantai.
flexible riser didesign dengansedemikian rupa agar mampubertahan pada kondisi bebanlingkungan yang mengenainya.
PERUMUSAN MASALAH
Berapa besar maksimum tegangan akibat beban dinamis dan minimum bending radius yang dialami oleh flexible riser saat ballast dan fully loaded ?
Jarak yang diijinkan antara flexible riser dan seabed, jarak antara flexible riser dan mooring line.
TUJUAN
Mengetahui besar maksimum tegangan akibat beban dinamis dan minimum bending radius yang terjadi pada flexible riser saat ballast dan fully loaded.
Mengetahui jarak yang diijinkan antara flexible riser dan seabed, dan jarak antara flexible riser dan mooring line.
BATASAN MASALAH
Struktur terapung yang akan dianalisa adalah FPSO Brotojoyo.
Semua peralatan dan perlengkapan di atas FPSO tidak dimodelkan.
Tidak membahas riser akibat beban internal. Pemodelan mooring hanya untuk mengetahui maximum
offset FPSO yang terjadi. Analisa perhitungan dalam tugas akhir ini menggunakan
software ORCAFLEX untuk mendapatkan tegangan akibat beban dinamis dan dibantu dengan softwareMOSES untuk mendapatkan nilai RAO dan wave drift.
Analisa motion kapal akibat sloshing diabaikan. Seabed dianggap datar.
METODOLOGI PENELITIAN 1
METODOLOGI PENELITIAN 2
DATA LINGKUNGAN
Parameter Units Value
Tinggi Gelombang (Hs) m 6.2
Periode Gelombang s 8.9
Kedalaman m 90
Kecepatan Arus m/s 0.98
Kecepatan Angin m/s 19.8
DATA FPSO
Spesifikasi FPSO
Parameter Units ValueLength over all (LOA) m 202.517Depth Moulded @ m 18.68Breadth Moulded m 38.4Vessel Draft Fully Loaded m 11.899Vessel Draft Ballasted m 4.96Displacement (Ballast) te 27,914.10Displacement (fully loaded) te 72,082.90
DATA FLEXIBLE RISER
Parameter Unit Value
Pipe OD mm 211.0
Pipe ID mm 152.4
Axial stiffness te 50
Horizontal Length from WHP to Vessel m 140
Length from WHP to attached Riser point on Vessel
m 200
Minimum bend radius m 1.82
Hang-off angle deg 15
DATA MOORING
Parameter Unit Value Type - ChainChain Size mm 87 (3.425)Chain Break Load te 616.199Chain Weight InWater
te/m 0.131
Weight in Air te/m 0.151Anchor Type - Stevpris 8 x 14 tonnes
PEMODELAN FPSO DENGAN MOSESFPSO dimodelkan secara sederhana dimana yang dimodelkan hanya hull-nya saja.
PEMODELAN DENGAN ORCAFLEX
GAMBAR MODEL FPSO
Saat kondisi Ballast dan Fully Loaded
Fully loaded dengan panjang riser 180 m
Ballast dengan panjang riser 180 m
VALIDASI MODEL
ITEM DATA MODEL VALIDASI
Displacement 50626.47 T 50184.71 T 0.87%
VCB 4.32 m 4.34 m 0.28%
LCB 90.11 m 89.99 m 0.13%
LCF 92.63 m 92.71 m 0.09%
KML 444.79 m 445.10 m 0.07%
RAO FPSO
Kondisi Fully Loaded
-0.2
0
0.2
0.4
0.6
0.8
1
1.2
0 0.5 1 1.5 2 2.5
Am
plit
udo(
m/m
)
Frekuensi Encounter (rad/sec)
Brotojoyo AnalysisVessel Motion
surgeswayheaverollpitchyaw
LANJUTAN.
00.5
11.5
22.5
0 1 2 3
Am
plit
udo(
m/m
)
Frekuensi Encounter (rad/sec)
Brotojoyo AnalysisVessel Motion
surgeswayheaverollpitchyaw
0123
0 1 2 3
Am
plit
udo(
m/m
)
Frekuensi Encounter (rad/sec)
Brotojoyo AnalysisVessel Motion 45
surgeswayheaverollpitch
00.5
11.5
22.5
0 1 2 3
Am
plit
udo(
m/m
)
Frekuensi Encounter (rad/sec)
Brotojoyo AnalysisVessel Motion 45
surgeswayheaverollpitchyaw
00.5
11.5
22.5
0 1 2 3
Am
plit
udo(
m/m
)
Frekuensi Encounter (rad/sec)
Brotojoyo AnalysisVessel Motion 45
surgeswayheaverollpitchyaw
NILAI TERTINGGI GERAKAN FPSO KONDISI FULLYLOADED
Heading Surge Sway Heave Roll Pitch Yaw
0 0.916 0.005 0.956 0.442 0.973 0.005
45 0.662 0.654 0.98 2.296 1.206 0.447
90 0.068 0.947 1.523 3.763 0.518 0.052
135 0.662 0.654 0.98 2.438 0.972 0.477
180 0.915 0.002 0.956 0.451 0.786 0.006
KONDISI BALLAST
2.0944, 02.0944, 0.0032.0944, 0.0012.0944, 0.0022.0944, 0.0022.0944, 0.0020
0.2
0.4
0.6
0.8
1
1.2
0 0.5 1 1.5 2 2.5
Am
plit
udo(
m/m
)
Frekuensi (rad/sec)
Brotojoyo AnalysisVessel Motion 0
surgeswayheaverollpitchyaw
LANJUTAN.
0
0.5
1
1.5
2
0 0.5 1 1.5 2 2.5
Am
plit
udo(
m/m
)
Frekuensi (rad/sec)
Brotojoyo AnalysisVessel Motion 45
SurgeSwayHeaveRollPitchYaw
012345
0 0.5 1 1.5 2 2.5Am
plit
udo(
m/m
)
Frekuensi (rad/sec)
Brotojoyo AnalysisVessel Motion 90
SurgeSwayHeaveRollPitchYaw
00.5
11.5
22.5
0 0.5 1 1.5 2 2.5
Am
plit
udo(
m/m
)
Frekuensi (rad/sec)
Brotojoyo AnalysisVessel Motion 135
SurgeSwayHeaveRoll
00.20.40.60.8
11.2
0 0.5 1 1.5 2 2.5
Am
plit
udo(
m/m
)
Frekuensi (rad/sec)
Brotojoyo AnalysisVessel Motion 180
SurgeSwayHeaveRollPitchYaw
NILAI TERTINGGI GERAKAN FPSO KONDISI FULLYLOADED
Heading Surge Sway Heave Roll Pitch Yaw
0 0.938 0.029 0.958 0.857 1.02 0.031
45 0.678 0.666 0.978 1.639 1.094 0.394
90 0.052 0.963 1.283 4.644 0.427 0.057
135 0.077 0.665 0.978 1.28 1.083 0.406
180 0.938 0.028 0.958 0.479 1.017 0.025
ANALISA TEGANGAN
SAAT KONDISI BALLAST (180 m)Heading
PembebananAttachmen
t PointEffective Tension (kN) Max. Tension (kN) Criteria(kN)Riser 1 Riser 2 Riser 1 Riser 2 Riser Remark
0 FPSO 45,185 42,717 60,702 53,981 < 167,9 ok
WHP 26,340 27,743 34,496 35,019 < 167,9 ok
45 FPSO 45,017 44,737 59,643 58,140 < 167,9 ok
WHP 25,008 26,560 35,319 38,209 < 167,9 ok
90 FPSO 43,941 45,732 71,956 74,851 < 167,9 ok
WHP 23,896 25,470 41,386 43,208 < 167,9 ok
135 FPSO 41,620 46,575 52,416 53,116 < 167,9 ok
WHP 24,580 26,279 33,574 34,079 < 167,9 ok
180 FPSO 40,076 47,636 46,469 59,422 < 167,9 ok
WHP 26,216 28,289 36,623 38,628 < 167,9 ok
Heading Pembebanan
Bending Radius (m) Criteria (m)
Riser 1 Riser 2 Riser Remark
0 6,590 6,606
> 2,75 ok
45 6,643 6,725
> 2,75 ok
90 7,701 7,755
> 2,75 ok
135 8,610 8,439
> 2,75 ok
180 7,179 6,937
> 2,75 ok
SAAT KONDISI BALLAST (200 m)Heading
PembebananAttachmen
t PointEffective Tension(kN) Max. Tension(kN)
Criteria (kN)Riser 1 Riser 2 Riser 1 Riser 2 Riser Remark
0 FPSO 46,213 42,870 60,542 53,445 < 167,9 ok
WHP 27,793 29,614 33,828 35,214 < 167,9 ok
45 FPSO 46,369 45,975 61,144 59,267 < 167,9 ok
WHP 26,797 28,559 33,930 35,976 < 167,9 ok
90 FPSO 45,692 47,606 73,032 75,391 < 167,9 ok
WHP 25,627 27,351 40,921 42,699 < 167,9 ok
135 FPSO 42,828 48,153 54,637 56,511 < 167,9 ok
WHP 26,492 28,235 32,945 33,948 < 167,9 ok
180 FPSO 39,963 48,706 46,974 58,232 < 167,9 ok
WHP 27,921 29,830 35,736 37,706 < 167,9 ok
Heading PembebananBending Radius (m) Criteria (m)
Riser 1 Riser 2 Riser Remark
0 8,217 8,138 > 2,75 ok
45 7,568 7,544 > 2,75 ok
90 8,006 8,048 > 2,75 ok
135 9,172 9,237 > 2,75 ok
180 8,821 8,516 > 2,75 ok
SAAT KONDISI BALLAST (220 m)Heading
PembebananAttachmen
t Point
Effective Tension (kN) Max. Tension (kN) Criteria (kN)
Riser 1 Riser 2 Riser 1 Riser 2 Riser Remark
0 FPSO 47,831 44,336 61,916 55,276 < 167,9 ok
WHP 31,600 33,703 36,494 38,564 < 167,9 ok
45 FPSO 48,052 47,742 62,617 61,034 < 167,9 ok
WHP 30,595 32,562 36,279 38,306 < 167,9 ok
90 FPSO 47,583 49,648 76,164 79,447 < 167,9 ok
WHP 29,348 31,219 45,387 46,750 < 167,9 ok
135 FPSO 44,577 50,047 58,573 60,477 < 167,9 ok
WHP 30,421 32,268 35,901 36,844 < 167,9 ok
180 FPSO 41,334 50,219 49,121 57,917 < 167,9 ok
WHP 31,753 33,679 37,752 39,544 < 167,9 ok
Heading Pembebanan Bending Radius (m) Criteria (m)
Riser 1 Riser 2 Riser Remark
0 8,606 8,480 > 2,75 ok
45 7,583 7,525 > 2,75 ok
90 7,362 7,416 > 2,75 ok
135 8,932 8,958 > 2,75 ok
180 9,393 9,015 > 2,75 ok
SAAT KONDISI FULLY LOADED (180 m)Heading
Pembebanan
Attachment Point
Effective Tension (kN) Max. Tension (kN) Criteria(kN)Riser 1 Riser 2 Riser 1 Riser 2 Riser Remark
0 FPSO 37,472 36,123 50,488 43,480 < 167,9 ok
WHP 26,868 28,479 36,530 39,083 < 167,9 ok
45 FPSO 37,188 37,690 48,461 47,210 < 167,9 ok
WHP 25,058 26,776 37,899 39,292 < 167,9 ok
90 FPSO 36,493 38,275 47,868 49,637 < 167,9 ok
WHP 24,972 26,662 32,261 33,800 < 167,9 ok
135 FPSO 35,208 39,085 42,853 47,170 < 167,9 ok
WHP 25,524 27,257 31,073 33,109 < 167,9 ok
180 FPSO 34,889 39,601 39,357 45,841 < 167,9 ok
WHP 27,148 29,096 34,780 36,273 < 167,9 ok
Heading PembebananBending Radius (m) Criteria (m)
Riser 1 Riser 2 Riser Remark
0 4,869 7,596 > 2,75 ok
45 4,580 4,714 > 2,75 ok
90 4,945 4,914 > 2,75 ok
135 6,315 5,993 > 2,75 ok
180 7,505 7,499 > 2,75 ok
SAAT KONDISI FULLY LOADED (200 m)Heading
PembebananAttachmen
t PointEffective Tension (KN) Max. Tension (KN) Criteria (kN)
Riser 1 Riser 2 Riser 1 Riser 2 Riser Remark
0 FPSO 39,366 35,446 59,880 53,499 < 167,9 ok
WHP 28,137 29,937 37,350 40,414 < 167,9 ok
45 FPSO 38,807 24,043 55,163 60,349 < 167,9 ok
WHP 28,664 19,808 39,916 50,056 < 167,9 ok
90 FPSO 36,661 38,434 58,599 60,289 < 167,9 ok
WHP 26,447 28,257 37,829 39,596 < 167,9 ok
135 FPSO 41,879 33,922 57,982 62,674 < 167,9 ok
WHP 28,613 21,239 37,896 57,751 < 167,9 ok
180 FPSO 41,598 30,068 53,023 63,825 < 167,9 ok
WHP 30,292 17,735 41,559 51,567 < 167,9 ok
Heading PembebananBending Radius (m) Criteria (m)
Riser 1 Riser 2 Riser Remark
0 5,288 6,588 > 2,75 ok
45 5,412 6,152 > 2,75 ok
90 3,230 3,231 > 2,75 ok
135 5,550 5,487 > 2,75 ok
180 5,195 5,348 > 2,75 ok
Heading Pembebana
nAttachment Point
Effective Tension(kN) Max. Tension (kN) Criteria (kN)
Riser 1 Riser 2 Riser 1 Riser 2 Riser Remark
0 FPSO 41,176 37,121 60,949 55,463 < 167,9 okWHP 31,695 33,827 40,118 43,277 < 167,9 ok
45 FPSO 40,877 24,450 55,190 54,901 < 167,9 okWHP 32,608 17,288 38,591 34,783 < 167,9 ok
90 FPSO 40,510 52,253 63,433 69,528 < 167,9 okWHP 32,194 18,412 40,023 30,748 < 167,9 ok
135 FPSO 38,116 43,921 56,507 61,925 < 167,9 okWHP 30,669 32,486 40,743 40,490 < 167,9 ok
180 FPSO 35,990 43,341 43,760 52,212 < 167,9 okWHP 32,004 33,944 40,165 41,901 < 167,9 ok
Heading PembebananBending Radius (m) Criteria (m)
Riser 1 Riser 2 Riser Remark
0 5,314 6,861 > 2,75 ok
45 5,509 6,103 > 2,75 ok
90 3,277 3,279 > 2,75 ok
135 5,552 5,545 > 2,75 ok
180 5,498 5,675 > 2,75 ok
SAAT KONDISI FULLY LOADED (220 m)
KESIMPULAN
Panjang riser (m)
Max. Tension (kN) Criteria (kN)
riser 1 riser 2 riser remark
180 71,956 74,851 < 167,9 OK
200 73,032 75,391 < 167,9 OK
220 76,164 79,447 < 167,9 OK
1. Tegangan Maksimum dan Bending RadiusBallast Fully Loaded
Panjang riser (m)Bending Radius (m) Criteria (m)
riser 1 riser 2 riser remark
180 8,61 8,439 > 2,75 OK
200 9,172 9,237 > 2,75 OK
220 9,393 9,515 > 2,75 OK
Panjang riser (m)Max. Tension (kN) Criteria (kN)
riser 1 riser 2 riser remark
180 50,488 49,637 < 167,9 OK
200 59,880 63,825 < 167,9 OK
220 63,433 69,528 < 167,9 OK
Panjang riser (m)Bending Radius (m) Criteria (m)
riser 1 riser 2 riser remark
180 7,505 7,596 > 2,75 OK
200 5,550 6,588 > 2,75 OK
220 5,552 6,681 > 2,75 OK
2. Jarak yang diijinkan antara flexible riserdan seabed berdasarkan (API 17B, hal :62) adalah 10 m, dengan panjangmasing-masing flexible Riser 180 m, 200m,220 m saat kondisi ballast maupun fullyloaded memenuhi.
RENCANA KEGIATAN TUGAS AKHIR
No. KEGIATANBULAN KE-
1 2 3 4 5 6
1 Pencarian studi literatur.
2 Pengumpulan data.
3 Permodelan FPSO
4 Analisa RAO motion.
5Pemodelan FPSO kondisi Ballast Dan Fully
Loaded, Mooring dan Riser.
6Analisa tegangan dinamis pada Riser dan
minimum bending radius.
7 Pembuatan laporan tugas akhir
Analisa Tegangan Dinamis Flexible Riser Akibat Motion FPSO Saat Kondisi Fully Loaded Dan BallastLatar BelakangPerumusan MasalahTujuan Batasan MasalahMetodologi Penelitian 1Metodologi Penelitian 2Data Lingkungan Data FPSOData Flexible RiserData mooringPemodelan FPSO Dengan MOSESPemodelan dengan orcaflexSaat kondisi Ballast dan Fully LoadedValidasi ModelRAO FPSOLanjutan.Nilai tertinggi gerakan FPSO kondisi fully LoadedKondisi BallastLanjutan.Nilai tertinggi gerakan FPSO kondisi fully LoadedANALISA TEGANGANSlide Number 23Slide Number 24Slide Number 25Slide Number 26Slide Number 27kesimpulanSlide Number 29Rencana Kegiatan tugas akhirGambarSlide Number 32