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How to model a Pulled Bend and a does the AutoPIPE consider the thinning wall on the outer radius of a pulled bend?
A pulled bend is a bend that is formed by a machine wrapping the pipe around a shoe horn form (i.e. like a tubing bender bending tubing) Using AutoPIPE Nuclear version, with piping codes ASME NB, NC, or ND selected, users can set Bend Type = Pulled.
For other version of AutoPIPE, Standard or Plus (Advanced), using non-nuclear piping codes, to model a pulled bend, select Bend Type = "elbow", SIF and flexibility factor will automatically be calculated but suggest that bourdon pressure effect be turned on (Tools> Model Options> Edit> "Include Bourdon rotational effect" check ON).
One side effect of bending the work-piece is the wall thickness changes; the wall along the inner radius of the tube becomes thicker and the outer wall (extrafit) becomes thinner. AutoPIPE does not consider the different wall thickness. The wall thickness is a uniform value specified on the pipe properties dialog screen.
Note: When Bend Type = Pulled, User SIFs CANNOT be placed on an Bend component's Near or Far points. That is because on an actual Pulled Bend there is no physical joint at these locations. The nearest welds are further away from the bend than defined by a Near or Far point.
Bend & Miter Piping Components - Modeling Approaches
Bentley AutoPIPE