46. What methods are used to calculate the K factor from ASME VIII Div 1, appendix EE for use in a P


Answer:

Given the vessel is 6040mm dia with a wall thickness  = 20mm and Limpet / Half pipe coli with a pitch of 150 mm and 40 mm radius.

Referencing, ASME VIII Div 1, appendix EE, figure EE-2 (DN80), the K factor would be read, but parameter D is beyond the scope of the limits of the chart (D = 6040 mm / 25.4 mm = 237.79 in).

Other applications like PV Elite considers the Diameter D = 170 instead of 237.79, then they have a K value found from reading the chart. However, as mentioned, the actual geometry is beyond the chart.

How to best find the correct value of K ?

Upon further investigation of:

a. b. ASME VIII div.1 NONMANDATORY APPENDIX EE HALF-PIPE JACKETS,

b. ASME VIII div.2 4.11.5 DESIGN OF PARTIAL JACKETS

Find that ASME VIII div.2 4.11.5 uses equations instead of charts to determine the K factor. 

Therefore, the K factor obtain in AutoPIPE Vessel come from equations which are matching charts in the scope of ASME VIII div.1. In addition, there is no limitation explained in ASME VIII 2 about the scope of this application.