Hello,

Im analysing a cylindrical Heater outlet piping. The heater has 4 outlet nozzles. I have calculated the heater displacement on that 4 nozzle nodes and used it for my analysis. Then i have done nozzle analysis using WRC 107 Module. I have used displacement reaction of that 4 nozzles for this nozzle analysi. i want to confirm that whether this procedure is correct or not. And also when we have to use Nozzle option in the CAESAR II input spread sheet.

Methodology of analysis is correct. Tell me one thing : By Heater do you mean a Fired Heater as per API560? If so then nozzle loads have to be met as per API560 Requirements ( or may be a multiple of it if allowed in your project specification).Also check if the geometric requirements meet WRC107 application criteria.

Nozzle option is used for WRC297 (an extension of WRC 107 for cylindrical vessels ,having more geometric parameter flexibility and ability to calculate nozzle stress besides vessel stress), API650 ( Storage tanks ) and BS5500.

Anindya Bhattacharya

Stress Analyst

Bechtel Corporation

It's obviously going to depend on the particulars of your heater. But, if we're talking about a fired heater, I wouldn't expect WRC107 to give anything in the way of a useful result. Most of the fired heaters I've seen are such that the "nozzle" is simply packed hole in the heater box where the tube sticks out. It would be guided at the penetration and have a displacement based on movement from the internal support of the tube in the heater.

As there is not a true "nozzle", you're going to have to rely on the API560 as Anindya Bhattacharya indicates to validate your analysis.

I agree about using API 560 instead of WRC107 that doesn´t apply, as Edward said.
But I have a doubt, Is correct to model the Heater shell (like in a regular equipment)?? so the Heater will follow some displacemtens, also due to the temperature inside and use Cnodes to connect the heater wiht the internal coil supports and external supports(such as hangers for the pipe)??

Regards

Ofcourse, For Fired Heater also we need to model as like other equipment and consider the thermal analysis.

Rams,