Hi Aslam,
Thank you very much for your reply.

Incidentally: spring tables give theoretical installed loads and actual installed loads for variable springs, and hot load for constant springs. In the trials I did when compared spring table with the restraint summary, the theoretical installed as well as the actual installed loads are either very close to the sustained load or these loads are in between the values of operating and sustained loads. It seems that the WNC case will be the same. So once the nozzle load is checked for the operating and sustained loads it should be safe for WNC condition also.
For further discussion.