Design Responsibilities - ASME/NB & Industry Practice

[vehazle]

With respect to VIII, Div. 1, who has design responsibility for a vessel? Is it generally the U stamp holder whether they design the vessel themselves or contract the service?

Is there a clear position from the National Board?

The way I view it is that I am hiring the U stamp holder to supply a vessel compliant with the specifications (VIII-1 being one) I give him. My responsibility is to ensure I communicate the design requirements (diameter, length, nozzle sizes/locations/loads, specific material requirements, seismic/wind loading, etc)clearly. The U stamp holder is responsible for ensuring the resulting design takes these requirements into account and complies with both the design and manufacturing requirements of the Code.

Am I completely off base on my view of the design responsibility?

I am interested in what is common experience of other ASME vessel users/specifiers/U stamp holders.

Thank you for any input.

 

[vesselfab]

The ASME code requires the fabricator to be responsible for the mechanical design of the vessel.

Pressure/Temperature internal & external
Wind load
Seismic load
Direct loads on shell if given data
Nozzle loadings if given data

support design skirts, saddles, anchor bolts, Zick on saddles

the fabricator may hire a contractor to furnish the information but the assigned chief engineer must approve the design so fabricator is ultimately responsible

 

[metengr]

Is there a clear position from the National Board?

See the NBIC, design defaults back to the code of construction.