I’m designing a pressure vessel on saddle supports with nozzle at shell and heads. The nozzle is located at knuckle region of the torispherical head. I´ve calculated the nozzle geometry and it doesn´t need a reinforcement. But my question is: Is there a section on the code that suggests nozzle reinforcement when it is located at knuckle region of the head?
The knuckle region of a vessel is highly stressed and placing a nozzle in that region is not recommended. In fact PD5500 does not allow a nozzle to be placed within the knuckle region and specifies a distance within which a nozzle is not allowed.
Above is a snippet.