App 2 Loose flange and host setback distances
App 2 Loose flange and host setback distances
(OP)
I have an App 2 loose flange that is 3" thick per design that attaches to a 1/2" thk head using 1/2" fillet welds on both sides of the flange. I had asked the fabricator to purchase a head with a 3" straight flange, but the head was ordered with only a 1 1 2/" straight flange. Using a normal setback for the inner fillet weld causes the head to be down into the flange too far making the outer fillet to be more like a giant groove weld. The fabricator wants to set the head back into the flange by 1 1/2". This would keep the relationship of the flange and head more normal at the backside of the flange, but now I don't have a normal setback from the face of the flange. Are there any rules tha specifically address this setback distance?
Thanks in advance,
Michigander
Thanks in advance,
Michigander





RE: App 2 Loose flange and host setback distances
I suggest you listen to your fabricator.
RE: App 2 Loose flange and host setback distances
appendix 2 has rules
look at figure 2-4 page 350 of 2007 issue
says max set back is c+1/4"
if you are trying to save the head....fabricate and weld on a 1-1/2" to 2" long pup and weld to heat to simulate a 3"+/- sf. fully radiography the long seam and girth seam just so there is no questions asked later
RE: App 2 Loose flange and host setback distances
Fabricator needs too add short cylinder to vessel head then attach body flange. Steve
RE: App 2 Loose flange and host setback distances