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Monster Media 1996 #14
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Monster Media No. 14 (April 1996) (Monster Media, Inc.).ISO
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VESSEL.TXT
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1991-08-02
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METHODOLOGY
VESSEL DESIGN
The vessel volume and surface calculations are performed
using four types of heads. You may select Flat Heads, ASME
F&D,2-1 elliptical,or HemiSpherical Heads. The flexibility
to use different heads for the top and bottom was not
included. Designs with Hemi heads should be used with
caution, since it is unusual for them to be selected except
for very high pressure designs. Special design techniques
are often used for very high pressure applications that go
beyond the capabilites of this program.
Cylinder Volumes The volume of the vessel cylinder between
the seam to seam dimensions is base upon the internal
diameter in inches specified and the height given. The
formula for the volume is :
V = 3.1416/4 * (D/12)^2 * H/12 ft^3
The surface of the Cylinder is calculated by the formula
A = 3.14.6*D/12*H/12 ft^2
The thickness of the cylinder is calculated by the ASME
formulas
If P > 0.385 * S * E then the thick wall equation is used
T = R * ((S*E + P ) / (S*E - P))^0.5 - 1 + CA
ELSE The thin wall equation is used {this is the usual case}
T = (P*R / (S*E - 0.6*P) + CA
IF the calculated thickness is less then 0.25 inches then a
default thickness of 0.25 inches is used.
The weight of the cylinder is calculated by
W = A * T * METAL WEIGHT
with units corrected
The metal density used is 0.283 lb/ in^3 for steel
It can be changed as well as the values used for S, and E and
CA in the screen called up by pressing W from the command
line.
HEAD DATA
The data for the various heads is calculated as follows for
the head volume, surface areas, shell thickness and weight.
FLAT HEADS ( no design pressure calculation is made )
A = Pi/4*(D/12)^2
V = 0
DEPTH = 0
T = 0.25 in
ASME F&D
A = Pi*(D/24)^2 * ( 1 + X^2*(2 - X)
Where X = 0.3334
V = 2*0.1667*0.667*Pi*(D/24)^3*7.47
DEPTH = X * D/2
T = T by thin wall eq * 10.6 / 6 + CA
2-1 Elliptical
A = (Pi * (D/24)^2)*(1 + X^2*(2-X)
Where X = 0.5
V = 0.0005667*(D)^3
DEPTH = X * D/2
T = P*D / (2*(S*E - 0.1*P)) +CA
HEMISPHERICAL
A = 1.5708*(D/12)^2
V = 0.0011335 * (D^3)
DEPTH = D/2
T = (P*D/2) / (2*(S*E - 0.1*P)) +CA
UNITS
A = AREA FT^2
V = VOLUME IN GALLONS
DEPTH = INCH
D = INTERNAL DIAMETER INCH
T = THICKNESS INCH
CA = CORROSION ALLOWANCE INCH
P = DESIGN PRESSURE PSI
E = WELD EFFICIENCY 0.75 TO 1
R = RADIUS INCH
S = ALLOWABLE STRESS
LIQUID HEIGHT
The height of the liquid in the vessel is calcuated from the
bottom tangent or seam dimension. It is calculated from the
volume of the liquid inputted in the Liquid input section by
subtracting the volume of the bottom head and determining the
straight side volume of liquid.
The baffle width is calculated by
BW = D/12
The baffle offset from the wall is calculated by
BO = D/72
STRESS VALUES TO USE
Stress values vary with the type of metallurgy
typical values are as follows:
Metal Allowable Stress (psi)
SA515-55, SA516-55, SA285C 13700
SA515-60, SA516-60, SA-53B 15000
SA515-65, SA516-65 16200
SA515-70, SA516-70 17500
SA240, 304LSS, 316LSS 17500
SA240, 304SS, 316SS 18750
SA240, 321SS, 347SS 18750
SA240, 410SS 16250
MONEL 400 21000-30000
INCOLOY 600 26000-37000
TITANIUM 8700-16300
SA285C 20% 304 OR 316 CLAD 14700
HASTELLOY G 25100
CARPENTER 20 20000
ZIRCONIUM SB551 13050
TANTALUM 11250
ALUMINUM 5456 10200-11500
NICKEL SB-162 10000-13300
NICKEL SB-127 17500-18700
NICKEL SB-168 20000-21200
WELD EFFICIENCY VALUES
The value of weld efficiency to use in the thickness
calculation are determined by the weld procedures as follows:
TYPE OF JOINT FULL X RAY SPOT X RAY VISUAL
double butt weld 1.0 0.85 0.70
single butt weld 0.90 0.80 0.65
with backing strip
single butt weld
W/O backing strip --- --- 0.60
double full fillet
lap joint --- --- 0.55
single full fillet lj
with plug welds --- --- 0.50
single lap without
plug welds --- --- 0.45
METAL DENSITY
METAL DENSITY
LB/IN^3
CARBON STEEL 0.283
304 SS 0.301
316 SS 0.301
MONEL 400 0.324
ALUMINUM 0.0994
INCONEL 600 0.326
NICKEL 0.326
TITANIUM 0.1669
ZIRCONIUM 0.240
HASTELLOY G 0.3056
HASTELLOY C 0.327
HASTELLOY B 0.339
CARPENTER 20 0.330
TANTALUM 0.6079