This is my portofolio about static analysis xyz wellhead platform

1. STATIC ANALYSIS OF XYZ
WELLHEAD PLATFORM
BASED ON API RP2A WSD
Kristoforus Satya Anggara
Depok, 2021

2. Introducing
XYZ
WELLHEAD
PLATFORM

5. MAIN DATA
General Criteria Description
Recommended practice API RP2A WSD, AISC ASD
Material structure ASTM
Platform type Wellhead
Platform type 4
Water depth (LWS) - feet 115
Platform orientation +32,50
Deck Design Criteria Description
Number of deck 2
Cellar deck area 1400 ft2
Main deck area 1200 ft2
Cellar deck live load operating condition 100 psf
Main deck live load operating condition 100 psf

6. MAIN DATA (cont.)
Deck Design Criteria Description
Cellar deck live load operating condition 75 psf
Main deck live load operating condition 75 psf
Crane vertical load operating condition 155 kips
Crane moment load operating condition 220 kips.in
Crane vertical load storm condition 72,5 kips
Crane moment load storm condition 0 kips.in
Wind load operating condition 40 mph
Wind load storm condition 120 mph
Pipe load main deck 35 psf
Pipe load cellar deck 35 psf
Helicopter Boeing Boeing BO-105C
Helideck codes API RP2L

7. MAIN DATA (cont.)
Wind & Current Operating Condition
Significant wave height 8 ft
Wave period 9,5 s
Tide 4,8ft
Current speed (surface) 2 ft/s
Current speed (seabed) 0 ft/s
Wind & Current Storm Condition
Significant wave height 24 ft
Wave period 9,5 s
Tide 4,8 ft
Current speed (surface) 3 ft/s
Current speed (seabed) 0,8 ft/s
Storm surge 0,5 ft

8. MAIN DATA (cont.)
Jacket Design Criteria Description
Marine growth 2 inch
Scouring effect tolerance 3 feet
Number of conductor 6
Conductor OD 24 inch
Conductor thickness 0,625 inch
Soil type A
Batter 1/8

9. CELLAR DECK EQUIPMENT
No. Description Number
Weight
(kip)
SIZE
Length Width Height
ft inch ft inch ft inch
1 Emergency generator 1 20,16 22 9 10 11
2 Maintenance building 1 44,80 12 3 6 4 8
3 Switch gear 1 7,84 5 2 2 8 10
4 Switch gear building 1 6,72 7 18 13 6
5 Diesel fuel tank 1 58,24 10 10 10
6 Transformer-2 1 12,00 9 5 6 9

10. No. Description Number
Weight
(Kip)
SIZE
Length Width Height
ft inch ft inch ft inch
1 Instrument storage 1 5,60 8 6 8 6 6
2 Fresh water tank 1 7,09 11 6 8 10
3 Mechanical storage 1 7,84 8 2 8 1 8 9
4 Communication tower 1 17,92 10 5 10 5 100
5 Power instrument storage 1 4,44 8 2 8 2 9
6 Toilet 1 2,24 5 4 8
MAIN DECK EQUIPMENT

11. DECK SIZE
The size of the cellar and main deck is the same.
Length = 40 ft
Width = 40 ft
Area = 1600 ft2

12. ELEVATION
No. Name Descriptions
Value Elevation (ft) Elevation (ft)
(ft) (from Seabed) (from MSL)
1
Cellar Deck
(Top of Steel
Plate)
Water Depth
(LWL)
115
142 27
Tide at Storm 4,8
Storm Surge 0,5
Storm Wave
Amplitude
12
Air Gap
(Chakrabarti)
5
Plate Thickness 0,38
Main Girder
Depth
3,43
27
2
Main Deck
(Top of Steel
Plate)
Highest
Equipment on
Cellar
13,50
164 49
Clearance 5
Plate Thickness 0,38
Main Girder
Depth
3,43
Cellar Deck
Elevation
141,10
23

13. ELEVATION
(cont.)
23
3
Heli Deck
(Top of Steel
Plate)
Power instrument
storage
9
183 68
Clearance 6
Plate Thickness 1
Main Girder
Depth
3,04
Main Deck
Elevation
163,40
20
4
Jacket Elevation
(1st Level)
Water Depth 115
121 6
Tide at Storm 4,8
Strom Surge 0,5
10% Pasang
Surut
0,48
5
Working Point
Elevation
1st Level 121
124 9
Clearance (3 ft) 3
6 Pile Connection
Work point
Elevation
9 124 8
7 (2nd Level)
1st Level 121
91 -24,3
Span 30
8 (3rd Level)
2nd Level 90,8
61 -54,5
Span 30

14. ELEVATION
(cont.)
4
Jacket Elevation
(1st Level)
Water Depth 115
121 6
Tide at Storm 4,8
Strom Surge 0,5
10% Pasang
Surut
0,48
5
Working Point
Elevation
1st Level 121
124 9
Clearance (3 ft) 3
6 Pile Connection
Work point
Elevation
9 124 8
7 (2nd Level)
1st Level 121
91 -24,3
Span 30
8 (3rd Level)
2nd Level 90,8
61 -54,5
Span 30
9 (4th Level)
3rd Level 60,5
30 -84,8
Span 30
10
Mudline
Elevation
Water Depth 115 0 -115
11 Leg Extension
Water Depth 115
-3 -118
Scouring 3
12 Pile Stub 175,00

15. PRELIMINARY DESIGN SUMMARY
Deck
Profil Girder
Main Girder Secondary Girder
Cellar Deck W 24 x 68 W 33 x 130
Main Deck W 24 x 68 W 33 x 130
Heli Deck W 8 x 40 W 36 x 194
Tubular Member
Diameter
(in)
Ketebalan
(in)
Heli Deck Leg 21 0,5
Main Deck Leg 24 0,875
Cellar Deck Leg 35 0,875
Jacket Leg 45 0,875
Jacket Brace 15 0,625
Pile 35 0,625
Conductor 24 0,625
Conductor
Support Top
15 0,625
Conductor
Support Bottom
21 0,875

16. REDESIGN
There are several members which must be redesigned because it has UC > 1 when running by SACS
Name Descriptions OD (in) t (in) Di (in)
CDL Cellar deck leg 35 1 33
MDL Main deck leg 35 1 33
HDL Heli deck leg 35 1 33
CSU Conductor support 15 0,625 13,75
BRC Jacket brace 21 0,875 19,3
PLE Pile 38 0,875 36,3
MGH Main girder heli deck W 24 x 68

17. REDESIGN (cont.)
On the cellar deck and main deck, need to be added 2 main girders for support conductor because at
preliminary design, conductor does not count.

18. LOADING
• Because of the four legs, it is used 8 directions of enviromental attack for simulating the most critical
condition.
• That is 0o, 45o, 90o, 135o , 180o, 225o, 270o, 315o.
Load Case WSD
Operating Condition 0,6R = D + L +W
Normalized Value R = 1,67D + 1,67L + 1,67W
Storm Condition 0,8R = D + L +W
Normalized Value R = 1,25D +1,25L + 1,25W

19. GRAVITY LOAD ID
Load Condition Load ID Description
SW SW Self weight structure
EQMD EQMD Equipment main deck
EQCD EQCD Equipment cellar deck
BP
BPMD Pipe main deck
BPCD Pipe cellar deck
BCKO BCKO Crane at operating condition
BCKB BCKB Crane at the storm condition
BHKO
BHOMD Main deck life load at operating condition
BHOCD Cellar deck life load at operating condition
BHKB
BHBMD Main deck life load at storm condition
BHBCD Cellar deck life load at storm condition
BHLI
BHHD Heli deck life load
HELIWGHT Heli weigth

20. ENVIRONTMENT LOAD ID
Load Condition Load ID Description
ENO1 ENO1 Environmental load direction 0o at operating condition
ENO2 ENO2 Environmental load direction 45o at operating condition
ENO3 ENO3 Environmental load direction 90o at operating condition
ENO4 ENO4 Environmental load direction 135o at operating condition
ENO5 ENO5 Environmental load direction 180o at operating condition
ENO6 ENO6 Environmental load direction 225o at operating condition
ENO7 ENO7 Environmental load direction 270o at operating condition
ENO8 ENO8 Environmental load direction 315o at operating condition
ENB1 ENB1 Environmental load direction 0o at storm condition
ENB2 ENB2 Environmental load direction 45o at storm condition
ENB3 ENB3 Environmental load direction 90o at storm condition
ENB4 ENB4 Environmental load direction 135o at storm condition
ENB5 ENB5 Environmental load direction 180o at storm condition
ENB6 ENB6 Environmental load direction 225o at storm condition
ENB7 ENB7 Environmental load direction 270o at storm condition
ENB8 ENB8 Environmental load direction 315o at storm condition

21. OPERATING CONDITION
LOAD COMBINATION
Degre 0 45 90 135 180 225 270 315
Load Combination CO01 CO02 CO03 CO04 CO05 CO06 CO07 CO08
L
O
A
D
C
O
N
D
I
T
I
O
N
SW 1,67 1,67 1,67 1,67 1,67 1,67 1,67 1,67
EQMD 1,67 1,67 1,67 1,67 1,67 1,67 1,67 1,67
EQCD 1,67 1,67 1,67 1,67 1,67 1,67 1,67 1,67
BP 1,67 1,67 1,67 1,67 1,67 1,67 1,67 1,67
BCKO 1,67 1,67 1,67 1,67 1,67 1,67 1,67 1,67
BHKO 1,67 1,67 1,67 1,67 1,67 1,67 1,67 1,67
BHLI 1,67 1,67 1,67 1,67 1,67 1,67 1,67 1,67
ENO1 1,67
ENO2 1,67
ENO3 1,67
ENO4 1,67
ENO5 1,67
ENO6 1,67
ENO7 1,67
ENO8 1,67

22. STORM CONDITION
LOAD COMBINATION
Degre 0 45 90 135 180 225 270 315
Load Combination CB01 CB02 CB03 CB04 CB05 CB06 CB07 CB08
L
O
A
D
C
O
N
D
I
T
I
O
N
SW 1,25 1,25 1,25 1,25 1,25 1,25 1,25 1,25
EQMD 1,25 1,25 1,25 1,25 1,25 1,25 1,25 1,25
EQCD 1,25 1,25 1,25 1,25 1,25 1,25 1,25 1,25
BP 1,25 1,25 1,25 1,25 1,25 1,25 1,25 1,25
BCKB 1,25 1,25 1,25 1,25 1,25 1,25 1,25 1,25
BHKB 1,25 1,25 1,25 1,25 1,25 1,25 1,25 1,25
BHLI 1,25 1,25 1,25 1,25 1,25 1,25 1,25 1,25
ENB1 1,25
ENB2 1,25
ENB3 1,25
ENB4 1,25
ENB5 1,25
ENB6 1,25
ENB7 1,25
ENB8 1,25

23. RESULTS

24. MEMBER STRESS UC
Group ID Description
Maximum UC
Operating Storm
MGM Main deck main girder 0,466 0,782
MGC Cellar deck main girder 0,435 0,388
MGH Heli deck main girder 0,481 0,168
SGM Main deck secondary girder 0,334 0,417
SGC Cellar deck secondary girder 0,254 0,363
SGH Heli deck secondary girder 1,042 0,271
DLC Main deck leg - 0,402
DLH Cellar deck leg 0,151 -
DLM Heli deck leg 0,416 0,298

25. MEMBER STRESS UC (cont.)
Group ID Description
Nilai UC Maksimum
Operating Storm
L1A, L2A, L1B, L2B Jacket leg 0,428 0,433
BR 1-4 & XB A,B,1,2 Jacket brace 0,487 0,239
P1A, P2A, P1B, P2B Pile 0,274 0,477
CON Conductor 0,391 1,136
CST Conductor support top 0,4 0,412
CSU Conductor support bottom 1,054 0,289

26. Operating
Condition

27. Storm
Condition

28. MORE INFORMATION
+You can access my paper in
https://its.academia.edu/KristoforusSatyaAnggara
+You can also email me in kristoforussatya1997@gmail.com