Engineers' Guide to Pressure Equipment - Index of

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Engineers’ Guide to Pressure Equipment
Fig. 3.12 Vessel weld types
For torispherical ends and ellipsoidal ends the method is to use ‘design
curves for dished ends’, which are a graphical representation of the above
formulae, modified slightly for ellipsoidal and torispherical ends. The steps
are outlined below.
• First, the code limits for dished ends should be satisfied. These are:
a) hemispherical ends : 0.002 D o ≤ t ≤ 0.16 D o
b) ellipsoidal ends : 0.002 D o ≤ t ≤ 0.08 D o
h e ≥ 0.18 D o
c) torispherical ends : 0.002 D o ≤ t ≤ 0.08 D o
r ≥ 0.06 D o
r ≥ 3t
R ≤ D o
where R = crown radius and r = knuckle radius (see Fig. 3.6).
• Next the value h e is determined (see the standard EN 286 for definitions).
h e is the smallest of the following: