The engineering task
Connected piping applies three forces and three moments to a nozzle in a cylindrical shell. Acceptable piping stress does not automatically imply an acceptable vessel nozzle. Internal pressure, local shell effects and multiple operating states require a separate vessel-side combination.
Thin shells, large nozzle diameters, short necks and nearby discontinuities are particularly critical. Loads from different coordinate systems must be transformed unambiguously; signs and simultaneity must not be distorted by indiscriminate absolute-value addition.
Required design data
- Nozzle, reinforcement and shell geometry
- Piping loads for operating, test and upset cases
- Global and local coordinate systems
- Pressure, materials and allowable stresses
Technical solution approach
Clean up the load interface
Fix coordinates, signs, application point and simultaneity of piping loads.
Verify pressure reinforcement
Check the nozzle's required reinforcement area independently of external loads.
Calculate local shell effects
Convert forces and moments into membrane and bending stress in the cylindrical shell.
Combine load cases
Combine internal pressure and external load components according to their actual simultaneous occurrence.
Release interface loads
Document utilisation and return allowable loads or reinforcement requirements to the piping engineer where necessary.
Expected deliverables
Suitable SOL ALPHA modules
The modules form a technically plausible toolchain. Their final selection and sequence will be confirmed during the later calculation against the applicable code and project conditions.