scope:

This AD 2000-Merkblatt applies to the calculation of local static or quasi-static stresses in pressure vessel walls in the vicinity of nozzle-to-shell-junction due to pressure loading and additional external forces and moments. The position of the nozzles is generally assumed to be vertical to the basic shell (radial nozzle). For nozzles located in the area of spherical part or knuckle of domed ends, the axis of the nozzle may be parallel to the axis of the vessel. If nozzles on vessels have a supporting function for the vessel, more detailed considerations may be necessary.

A verification is not required if each of the following conditions is complied with:

- The nozzle is a attached to the basic shell by a through-penetration weld.

- The minimum nozzle wall thickness complies with DIN 28115 for ferrous materials and with DIN 28025 Part 1 or 2 for austentic materials.

- The support intervals and flexural behavior of the connected piping shall comply with the support interval table or the flexibility nomogram of series HP 100 R of AD 2000-Merkblatter.

- The diameter d_i of the support shall not exceed 0,3 times D_i.

- The design to withstand internal pressure in accordance with AD 2000-Merkblatter B 3, D 9 and B 1 shall be based on a 10% increase in internal pressure in which case the basic shell and/or nozzle is to be reinforced, if required.

- The design does not include a verification against failure due to excess of creep rupture strength