Design of Tube Sheets with NTIW Tube layout.

[DK44]

As per ASME SEC VIII Div 1 UHX-10(c), the rules are applicable for Tube sheets that are uniformly perforated over a nominally circular area. Hence it is understood that,they cannot be applied for Tube sheet having Tube layout for No Tube In Window (NTIW) baffles having large un-tubed area and that U2(g) shall be applied.
In these circumstances I have following queries.
1) Does TEMA Tube Sheet design has any such limitation.
2) Is TEMA applicable for such Tube sheet designs.
3) Can TEMA calculations be applied as an acceptable U2(g) option.
4) Though not complying the Tube layout, can the Code be still employed for the Tube sheet design as a conservative approach and is it acceptable to code.

 

[SnTMan]

DK44, 1) Yes
2) No, see TEMA Non-Mandatory Appendix A, A.11 (3)
3) I'd I say yes, with client approval if relevant
4) Yes, NTIW designs are very common and designed to Part UHX all the time. Although it may become troublesome in certain jurisdictions.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand