UNIVERSITI TEKNOLOGI PETRONAS WELL DESIGN AND COMPLETION QUIZ 1
January 18, 2009 Ref: SH/D52/18/1/09
M/s. Cumberland Subject
: Acid Wash Tank – Design Calculations
Size
:
1250mm x 2050mm (Total height)
Design Standard – BS 4994, ASTM D 3299
Design Conditions: Design Pressure : Hydrostatic + 25000 Pa Design Vacuum – Directly vented. o Design Temperature – 55 C Specific Gravity – 1.24 Diameter – 1250mm Shell height – 2050mm Contents – Hydrochloric Acid Configuration – Vertical, Flat Bottom, Flanged Flat top Wind Loading – 160 Km/hr Design Factor (K)
K = 3 x K1 x K2 x K3 x K4 x K5 Where K1 = 1.5 for filament winding & hand lay up process. K2 = 1.2 K3 = 1.22 K4 = 1.1 K5 = 1.1 K = 7.97 = 8 Pressure = P = 1.24 x 1000 x 9.81 x 2.05m + 25000 = 0.5 bar Q
= 0.05 N/mm
2
= Circumferential unit load
= PD i 2
= 0.05 x 1250 = 31.25 N/mm. 2 1
Maximum allowable strain
CSM strain
= UL x 100% where UL = U XZ K =
Filaments strain
2000 x 100% 8 x 14000
= 0.17%
=
= 0.22%
Design strain d
500 x 100% 8 x 28000 = 0.17%
Allowable loads
1) CSM 600 g/m
2
U = 14000 x 0.0017 x 0.6 = 14.3 N/mm 2
2) Unidirectional filaments per Kg/m for 89 U
o
= 26000 x 0.0017 x 1 = 44.2 N/mm =0
UX
Proposed Construction 2
Two layers of 600g/m CSM – 2
o
6.5 Kg/m of 89 filaments Thickness
10 nos. of Radial – 2400 Tex.
= 3mm + 10 x 0.5 = 8 mm
ULam = 2 x 14.3 + 6.5 x 44.2
=
316 N/mm Q
ULamx = 2 x 14.3 +
=
28.6 N/mm QX (See page 4)
OK. Wind Load
Reference : BS CP3 Chapter V, Part 2. 2
VS = V S1 S2 S3 Where VS = Design wind speed V = Basic wind speed =160 Km/hr = 45m/s S1 = Topography factor S2 = Ground roughness & height factor S3 = Statistical factor
=1
=1
VS = 45 m/s 2
q = 0.603 x 45
= 1221 N/m
2
Cf shell
= 0.7 Pshell = 855 N/m
Cp top
= 0.8
2
Ptop = 977 N/m
2
Wind shear force = 855 x 1.25 x 2.1
= 2245 N
Wind overturning moment
Moment of Inertia
=I
= 2245 x 1.05 = 2360 Nm 4 = (D0 – D1 ) 64 4
4
4
= (1266 - 1250 ) 64 9
4
= 6.25 x 10 mm
QX1 QX2
= My x t = 2 N/mm = longitudinal loading due to bending under wind pressure I = longitudinal loading due to shelf weight of shell + Top cover 2
4
= (3.14 x 1.25 x 8 x 2.2 x 2.1 + 3.14 x 1.45 / 4 x 15 x 1.5 x 1.1) x 1.2 x 9.8) 3.14 x 1250 = 0.7 N/mm QX
= 2.7 N/mm Ulamx (See page 3)
OK. 3
Flat Top Head Design 2
Consider external load of 200 Kg/m = 2500 N/m
2
In addition to the wind load of P total = 1962 + 977 = 2940 N/m
2
Refer to equation BS 4994 eqn. (52) P45 2
MCSM =
P Db 5.33 tg UCSM
Where: 2
MCSM
= Total mass of glass per unit area (in Kg/m )
P
= Pressure = 6221 N/m
Db
= Bolt Circle diameter
tg
= Thickness per unit mass of glass = 2.125 mm per Kg/m
UCSM
2
= 0.00294 N/mm
2
= 1390mm
2
= Design unit loading = 14000 x 0.0017 x 0.45 = 10.7 N/mm
Mcs
= 6.845 Kg/m
t
= Mcsm 0.45
= 15mm. 2
Hence 15 layers of CSM 450g/m is sufficient for Top head cover. Flat bottom design
Since bottom fully supported on concrete, choose same thickness of shell, t = 8mm Bund Design
2400mm x 800mm height P
= 1.24 x 1000 x 9.81 x 0.8 + 25000 4
= 34, 732 N/mm Q
2
= 0.035 N/mm
2
= PDi = 0.035 x 2400 = 42 N/mm 2 2
Proposed Construction
2
2
o
2 CSM 600 g/m + 65 Kg/m of 89 filaments which will give U lam = 316>Q
t = 8mm OK. Bund flat bottom thickness
= 8mm
For bund top flange design refer to table 2 page 6 of ASTM D 3299 Flange dimension required width = 51mm x 8mm thick, instead use 100mm wide x 8mm thick.