Nozzle reinforcement at head
Nozzle reinforcement at head
(OP)
Has anyone ever used head nominal thickness instead of "minimum thickness after forming" for nozzle reinforcement calculation? Assuming the nozzle size is less than 30% of the head diameter so it won't fall in the knuckle area.
This "minimum" thickness is not " code minimum thickness". It is thin out after forming, normally happens in the knuckle area, which is approximate 1/8" less than the nominal thickness.
This "minimum" thickness is not " code minimum thickness". It is thin out after forming, normally happens in the knuckle area, which is approximate 1/8" less than the nominal thickness.





RE: Nozzle reinforcement at head
It is always best to error on the side of conservatism.
RE: Nozzle reinforcement at head
A thickness measurement might help, but you need to test several areas to have a trustworthy knowledge of the actual thickness in the nozzle area.
RE: Nozzle reinforcement at head
However, I have typically used the plate nominal thickness for the nozzles located in the centre of head, when I have had the confidence the thickness will not be altered. For other locations, there might be a chance of unexpected thinning.
I would say, you judge the location and the risk of thinner wall than expected.
Cheers,
gr2vessels
RE: Nozzle reinforcement at head
RE: Nozzle reinforcement at head
RE: Nozzle reinforcement at head
However, the use of nominal thickness in some cases is a common practice outside USA when bending a bit the rule could save significant money, without compromising the safety intent of the code.
Cheers,
gr2vessels