PD 6550-2:1989

Foreword
Committees responsible
1. Introduction
2. Branch compensation design
2.1 Stress distribution at nozzles
2.2 The main components of the method in 3.5.4 of
     BS 5500
2.3 The calculation stages
3. Flush branches in spheres and cones
3.1 Derivation of BS 5500, figure 3.5.4 (2)
3.2 Other aspects of the Leckie and Penny analysis
4. Shakedown applied to branch design
4.1 Fundamentals
4.2 Shakedown of a branch in a cylindrical shell
5. Protruding nozzles: derivation of BS 5500, figure
     3.5.4(1)
6. Flush branches in cylinders where 0 < d/D < 0.3:
     derivation of BS 5500, figure 3.5.4(3)
7. Flush branches in cylinders: where 0.2 < d/D      the equation for BS 5500, figure 3.5.4(4)
8. Other features of the method
8.1 Thick nozzles
8.2 Creep
8.3 Oblique nozzles
8.4 Limits of reinforcement
8.5 Reinforcing pads
9. BS 5500, appendix F
10. Multiple nozzles
11. BS 5500, appendix A
12. References
Table
1. The main components in BS 5500, figures 3.5.4(1)
     to (4)
Figures
1. Maximum principle stress contours for a nozzle in
     a sphere
2. Maximum principle stress contours for a nozzle in
     a cylinder
3. Stress distribution in the longitudinal plane along
     the inside surface of a cylinder and nozzle
4. Notation (for spheres)
5. Design curves for flush nozzles
6. Typical post-yield behaviour
7. Typical pressure-strain relationship at a
     discontinuity in a pressure vessel
8. Graphical derivation of the formula for a shakedown
     factor
9. Uniaxial stress state at a flush nozzle
10. Design curves for protruding nozzles
11. The cylinder-sphere approximation
12. C.R.I.F. fatigue test data
13. Area replacement method

Deals with the method for the design of branch connections given in clause 3.5.4 of BS 5500 being based on analysis rather than empirical rules which had shown itself to be safe and economic in the use of material. Also assesses the service performance of the most highly stressed region at the nozzle penetration.