Appendix 13 Plate Box Heat Exchanger Threaded connection/multi Diameter Ligament Efficiencies UG-54
Appendix 13 Plate Box Heat Exchanger Threaded connection/multi Diameter Ligament Efficiencies UG-54
(OP)
Hey everyone...I am validating a decade old program that calculates the Tube and Plug Sheet thickness per ASME and noticed a difference between what we use now and what this program uses. When it comes to the Threaded Plug sheet ligament calculation, can someone validate that it is calculating the D (diameter) of the threaded plug for the standard Bending/membrane Eff eb=em= (pitch- D)/ pitch calculation?
So if we have a 1.375"-12 UNF- 2B plug, what would you consider the value for D to be? Nominal Size/Major Diameter: 1.375", Basic Pitch Dia: 1.3209"...? The program has a preset table that doesnt state where the values come from:
Plug Size------D PLUG DIA
0.75-----------0.71875
0.875----------0.84375
1.125----------1.09375
1.25-----------1.34375
1.5------------1.59375
With that said, per ASME Section 8, is it generally understood that on the tubesheet side, that eventhough its ring and grooved, that we ignore the groove and just assume D is the tube diameter? Or is the industry standard that we calculate the D using 13.6 Multidiameter?
thank you!
So if we have a 1.375"-12 UNF- 2B plug, what would you consider the value for D to be? Nominal Size/Major Diameter: 1.375", Basic Pitch Dia: 1.3209"...? The program has a preset table that doesnt state where the values come from:
Plug Size------D PLUG DIA
0.75-----------0.71875
0.875----------0.84375
1.125----------1.09375
1.25-----------1.34375
1.5------------1.59375
With that said, per ASME Section 8, is it generally understood that on the tubesheet side, that eventhough its ring and grooved, that we ignore the groove and just assume D is the tube diameter? Or is the industry standard that we calculate the D using 13.6 Multidiameter?
thank you!




