Separate Design Codes for shell and tube bundle of the same HX

[starfarooq]

We have a vertical U-tube bundle type heat exchanger installed at our ammonia plant (Waste Heat Boiler). It was manufactured in 1975 on Stoom Weezen code. Now the bundle has completed its service life and we want to replace it, while keeping the existing shell unchanged. Our technical department is well versed in ASME code, therefore they want to design/manufacture the new bundle on ASME/TEMA code. Does the code allow that the bundle of an exchanger be manufactured as per ASME code while the code for shell be Stoom Weezen?

 

[XL83NL]

ASME design code(s), in your case most proably sect VIII-1, require the use of ASTM A/ASME SA (or ASTM B/ASME SB for non-ferrous), depending on code section.
Even though dual/triple/quadruple certification (i.e. according both EN and ASME) is pretty common nowadays, this want the case 40 years ago.

Im not sure what type of material grades/description Stoomwezen (I myself havent worked with it though Im dutch), but chances are very small they can be used for sect VIII-1 use.

However (this may be a litlle controversial/difficult), all the above is written for a 100% pure ASME vessel, as it should be, and how it's done in countries that regulate ASME code, like USA and Canada.
In the Netherlands you can design an ASME vessel (partly) with materials that arent in any ASME (sect. II), and still have the NoBo to approve it. It's done all the time, as for the European market one has to work acc. PED, not ASME. Perhaps this may allow you to use a partly refurbished vessel together with some new construction.

Therefore, if the vessel is for the Dutch market, or some other European country, I suggest you contact your NoBo. He can have an ultimate go/no go in this matter.

Good luck!