Example No. 1.1: Thick unwelded flat end
1. Material: P280GH according to EN 10222-2
The relevant heat treatment dimension is specified as 101.6 mm (in deviation from EN 10222-1).
2. Actions: Pressure PS = PSmaxDBF =17 MPa
x)
Temperature Tc =20°C
3. Operational cycles: T =const, p varying from 0 to Pop,sup =0.9⋅PS 4. Geometry: See Fig. 5.1
Fig. 5.1
x) A not very reasonable result: The end thickness is large and the ratio of admissible pressure to nominal design stress is outside the graphs and the scope of DBF. Extrapolation was necessary.
Specification of Examples
Design by Analysis 5.5
Example No. 1.2: Thin unwelded flat end
1. Material: P280GH according to EN 10222-2
The relevant heat treatment thickness is specified as 101.6 mm (in deviation from EN 10222-2).
2. Actions: Pressure PS =PSmaxDBF =4.2MPa Temperature Tc =20°C
3. Operational cycles: T =const, p varying from 0 to Pop,sup =0.9⋅PS
4. Geometry: See Fig. 5.2
Example No. 1.3: Welded-in flat end without nozzle
1. Material: P265GH according to EN 10028-2
2. Actions: Pressure PS = PSmaxDBF =12.7MPa Temperature Tc =20°C
3. Operational cycles: T =const, p varying from 0 to Pop,sup =0.9⋅PS 4. Geometry: See Fig. 5.3 and 5.4
Specification of Examples
Design by Analysis 5.7
Fig. 5.4
Example No. 1.4: Welded-in flat end with nozzle
1. Material: Plate and Shell: P265GH according to EN 10028-2 Nozzle: P265 according to prEN 10216-2
2. Actions: Pressure PS = PSmaxDBF =7.9MPa Temperature Tc =20°C
3. Operational cycles: T =const, p varying from 0 to Pop,sup =0.9⋅PS
Fig. 5.5
Specification of Examples
Design by Analysis 5.9
Example No. 2: Storage tank (cone-cylinder junctions)
1. Material: Shell: X6CrNiTi 18-10 (1.4541) according to prEN 10028-7 Reinforcing ring, foot ring: P235GH according to EN 10028-2; Note: the different thermal expansion coefficients shall be
considered.
2. Actions: Hydrostatic pressure p , medium density H ρM =1000kg m3 minimum medium level hMIN and maximum medium level
hMAX see Fig. 5.8. Note:
no longitudinal stress in the main cylindrical shell caused by hydrostatic pressure.
Temperature in service Tc =60°C; Temperature before complete filling of the vessel 20°C.
Internal pressure during draining (see also Fig. 5.9) MPa
PS =0.06 ;
Note: longitudinal stress in the main cylindrical shell caused by internal pressure acting on the upper end of the vessel. Dead load (self weight and insulation): Insulation:
2
220 N m
qd = (weight force / surface of the vessel), insulation thickness 200 mm; dead weight of roof including insulation and reinforcing ring 26,15 kN.
Wind load (limit value): stagnation pressure qW depending on
height h: 0m≤h≤6m: 2 / 81 . 0 kN m qW = : 10 6m<h≤ m qW =0.88kN/m2 : 15 10m<h≤ m 2 / 94 . 0 kN m qW = : 25 15m< h≤ m qW =1.02kN/m2 Wind force: Wi =c⋅qW,i⋅Ai
where c=0.44 and A = projection of the surface ofi the vessel in wind direction.
3. Detail to be investigated: wide and narrow ends of cone 4. Operational cycles: See Figure 5.9.
Note: It is ascertained that internal pressure can be increased only if the medium height is below hMIN. The
internal pressure increases slowly; for safety reasons both
extremes shall be considered, the very slow (dotted line) and very fast (full line) pressure increases.
Specification of Examples
Design by Analysis 5.11
Fig. 5.9
Example No. 3.1: Thin-walled cylinder-cylinder intersection
1. Material: P295GH according to EN 10028-2 2. Actions: Pressure PS = PSmaxDBF =0.28MPa
Nozzle longitudinal moment Mc =15644.4 Nm
(moment vector normal to plane through both cylinder axes).
Temperature Tc =50°C
3. Operational cycles: A) T =const, p varying from 0 to Pop,sup =0.9⋅PS, Mc =const
and
B) T =const, M varying from 0 to 26400 Nm, MPa
const p = =1.28
(for comparison with experimental results). Crotch corner surface machined: Rz =50µm
Note: Checks against GPD and PD, or SD, to be performed for constant longitudinal moment only.
Specification of Examples
Design by Analysis 5.13
Example No. 3.2: Thick-walled cylinder-cylinder intersection
1. Material: Shell: P265GH according to EN 10028-2
Nozzle: 11CrMo9-10 according to prEN 10216-2 2. Actions: Pressure PS = PSmaxDBF =14.09 MPa
Nozzle longitudinal momentMc =711.1Nm
(moment vector normal to plane through both cylinder axes).
Temperature Tc =50°C
3. Operational cycles: A)T =const, p varying from 0 to Pop,sup =0.9⋅PS, Mc =const and
B)T =const, M varying from 0 to1200 Nm, p=const =24MPa
(for comparison with experimental results). Crotch corner surface machined: Rz =50µm
4. Geometry: See Fig 5.11.
Note: See note in Example No. 3.1.
Fig. 5.11
1. Material: X6CrNiMoTi 17-12-2 (1.4571) according to prEN 10028-7 2. Actions: Pressure PS = PSmaxDBF =0.583MPa
Temperature Tc =180°C
3. Operational cycles: T =const, p varying from 0 to Pop,sup =0.9⋅PS 4. Geometry: See Fig. 5.12 and 5.13.
Fig. 5.12
Specification of Examples
Design by Analysis 5.15
Example No. 5: Nozzle in spherical end with cold medium injection
1. Material: Shell: 11CrMo9-10 according to EN 10028-2
Nozzle reinforcement: 11CrMo9-10+QT according to prEN 10216-2
Nozzle: P265 according to prEN 10216-2
2. Actions: Pressure PS =0.9⋅PSmaxDBF =0.9⋅13.01=11.71MPa
Temperature of medium inside the vessel TS =325°C (constant in operation).
Temperature of injected cold medium TN =80°C.
Location of different heat transfer coefficient for cold medium injection see Fig. 5.15. The outer surface of the vessel is insulated ideally.
Heat transfer coefficients:
-) medium to vessel wall, and to nozzle if there is no injection: hS =1.16kW m2K
-) cold (injection) medium to nozzle wall during injection: hN =10.8kW m2K .
3. Operational cycles: See Fig. E 5.15.
Cold medium injection takes place for 10 minutes. The time between the injection cycles is long enough such that temperature reaches , stationarity. After 500 injection cycles one shutdown (and startup) should be considered. At shutdown and startup, pressure and temperature are decreased or increased in phase, respectively. Temperature changes during shutdown and
startup are slow, and therefore thermal stresses can be neglected. 4. Geometry: See Fig. 5.14
Fig. 5.14
Specification of Examples
Design by Analysis 5.17
Example No. 6: Jacketed vessel with jacket on cylindrical shell only, and flat annular end plates
1. Material: X6CrNiTi 18-10 (1.4541) according to prEN 10028-7 2. Actions: Inner space: Pressure PS =−0.1/+1.3MPa
Temperature Tc =TS =160°C Outer space: Pressure PS =0/+0.5MPa
Temperature Tc =TS =160°C 3. Operational cycles: See Fig. 5.18.
Inner space: Pop,sup =1.1MPa Pop,inf =0MPa
TS
Top,sup = Top,inf =20°C .
Outer space: Pop,sup =0.45MPa Pop,inf =0MPa
TS
Top,sup = Top,inf =10°C
A pressure in the inner space below atmospheric can occur independently and repeatedly in operation, and an underpressure will occur concurrently with an outer space temperature of 10°C (whereby an inner space temperature value of 160°C shall be used). This case shall be included as a normal operating condition in the check against GPD, I, PD, or SD, but not in the fatigue check. A pressure in the outer space below atmospheric cannot occur, but a minimum pressure of 0 bar cannot be excluded. This case shall also be included as a normal operating condition in the check against GPD, I, PD, or SD (with temperatures in the inner and outer space of 160°C). Note: Top,sup and Top,inf are medium temperatures. The wall temperatures shall be determined using heat transfer coefficients of hi =1.16kW m2Kon inside of inner vessel wall and
K m kW h o 2 4 . 14
= on all surfaces of the inside of the jacket. Jacket and main vessel outside of jacket are insulated ideally.
Note: checks against GPD, I, PD or SD shall be performed usingthe PS values.
Note: only steady state thermal stresses shall be considered.
The maximum allowable out-of-roundness of the inner cylindrical shell is specified in prEN13445-3 as (D+1250) / 200 = (2780 + 1250) / 200 = 20,15 mm, where D is the mean shell diameter.
4. Details to be investigated: Jacket and jacketed part of inner vessel 5. Geometry: See Fig. 5.16 and 5.17.
Fig. 5.16
Specification of Examples
Design by Analysis 5.19
Fig. 5.18
160°C
P 235 GH
Specification of Examples
Design by Analysis 5.21
P 295 GH
1.4541