PD 6497:1982

Foreword
Cooperating organizations
0 Introduction
1 Scope
2 Reference
3 Notation
4 Longitudinal bending moments
5 Longitudinal bending stresses due to the bending
    moments
6 Shearing stresses
7 Circumferential stresses
8 Stiffening rings in the region of the saddle
9 Forces on the saddle
10 Ring supports for horizontal vessels
11 Concluding comments
Appendix
A Bibliography
Tables
1 Values of K1 and K2
2 Values of K3 for unstiffened shell
3 Values of K3 relevant to the end stiffened vessel
4 Values of K4 for dished end
5 Values of K5 for maximum circumferential stress at
    phi = pi
6 Values of moments at A, the turning value and the
    value at horn B
7 Values of Pt, MA, Mbeta and Pbeta in ring in the
    plane of the saddle
8 Moment values in the rings adjacent to the saddle
9 Values of the direct force at phi = rho
10 Values of K9 for various saddle angles
11 Moment values for ring supports
12 Maximum moment values for ring supports
Figures
1 Cylindrical vessel on saddles
2 Hydrostatic pressure
3 The vessel as a beam
4 Effective shell at the saddles
5 Angles on the vessel profile
6 Shear stress on the vessel
7 Distribution of shear force
8 Effective section for shear (alpha < phi < pi)
9 Distribution of shear force
10 Shear force near the end closure
11 Distribution of shear stress near end
12 Distribution of shear stress
13 Shell as an arch cut at the top dead centre A and
    supported at B
14 Unit moment diagram
15 Unit force diagram
16 Distribution of circumferential moment
17 Diagrammatic representation of width of shell
    resisting Mbeta
18 Circumferential bending moment constant, K6
19 Internal ring stiffener with part of shell carrying
    the moment
20 Forces on the ring
21 External ring stiffeners
22 Ring tangentially supported at B
23 Unit moment diagram
24 Unit force diagram
25 Variation of circumferential moment with phi (for
    saddle angle theta = 120 degrees)
26 Internal rings adjacent to saddle
27 Forces on the ring
28 Forces in the saddle
29 Radial forces on the vessel at saddle/vessel
    interface
30 Ring supported vessel
31 Ring supported vertically at B
32 Variation of circumferential moment with phi
    (support phi1 = 60 degrees)

Gives a commentary on the background of requirements of G.3.3 of BS 5500 and derives the associated equations from first principles with reference to papers by L P Zick and other authors.

This Published Document gives a derivation, from first principles, of the equations used in G.3.3 of BS 5500:1982 describing the stresses in horizontal pressure vessels supported on twin saddles.

It does not comment on the design aspects of the requirements of G.3.3, since these are considered to need no further clarification.