UNDER-BOTTOM CONNECTIONS AS PER APPENDIX O3 FIG. O1 & TABLE O1-aFrom: SANDESH 
Date: Thursday, March 29, 2012
Time: 10:20:38 AM
Remote Name: 188.8.131.52
I would like to know about under bottom connection design requirement as per appendix O3 FIG O1 & TABLE O1-a.
can any body intreprete the para O3. & explain me Fig O1.
client is aksing us to design of under bottom connection as per appendix O3 ,figure O1.
under bottom drain nozzle connection is 12 inch. so as per Table O1-a thickness of plate is 16 mm.
my doubt is under bottom PLATE material is A516 Gr.70 Group.IV due to thickness 16 mm PWHT is necessary for this connection insert plate area. pls. clarify to me.
Also does code says PWHT is required for this type of nozzle connection bottom insert plate when plate thickness is 16 mm and above?
Expecting your immediate reply