PED TS Max for heat exchanger tubes

[ceprab]

I have a possible problem with a condenser I have on a current project.

The Condenser is PED certified with notified body nameplate etc.

The nameplate states

Des. Temp. (Int/Ext)(TS Max) °C Shell Side 200 / 200 Tube side 80 / --

The problem I have is that in one case of coolant pump trip (through the tube side), the upstream equipment will trip leading to the expected temperature entering the shell side being 104°C with no coolant flow. The tubes will therefore approach the shell side temperature.

I know (and have documentation to demonstrate) that the tubes are OK at 200°C and higher. I have no concerns about the actual safety of the equipment, but am I right in thinking that the TS declaration above means that I cannot put this into service because the declared tube maximum temperature will be exceeded?

The supplier claims this is covered by the 200°C declaration of the shell side. I am sceptical.

Can anyone advise on where I stand? Am I just going off on one?

Thanks

Richard

 

[XL83NL]

Do you have a photocopy of the nameplate? From the info provided it's hard to exactly understand what you mean with

Des. Temp. (Int/Ext)(TS Max) °C Shell Side 200 / 200 Tube side 80 / --

Wrt your question;

but am I right in thinking that the TS declaration above means that I cannot put this into service because the declared tube maximum temperature will be exceeded?

I tend to think you're right; you cant put the equipment in service as the expected metal temperature may be higher than the nameplate allowable. The risks involved should be covered in the risk analysis. The results of the risk analysis should normally result in a proper design. If the risk you mentioned isnt a real risk of safety concern, this might not need to be addressed in the allowable TS of the equipment, and hence no problem. However, if the pump trip is a real issue, and the HEX supplier (nor the NoBo) may not know this issue with the pump trip, the question then is; who's to blaim? Such info might have been needed to be put on the data sheet of the equipment which is used to quote the HEX. To go one step further, this may also mean your P&ID is incorrect and no proper HAZOP has been conducted, leading to incorrect spec breaks.