Project Proposal Presentation.pptx
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Chris Wowk
MANE 6970
Master’s Project
Bolted, flat faced flanges are typical for fluid power applications when
disassembly of the joint is required for maintenance or access to the
internals of the system. The design of these flanges is typically
governed by requirements outlined in the ASME Boiler and Pressure
Vessel Code. For flange designs that come into contact with one
another outside of the bolt circle, additional analysis is required to
account for the interactions that occur due to the flexibility of each
flange.
Separation of this joint
leads to leakage and
higher than predicted bolt
prying loads
Fluid
Pressure
Prying Load
Outside Bolt
Circle
Design and analysis of these bolted joints are
covered by Appendix Y or ASME Boiler and Pressure
Vessel Code (BPVC)
◦ Plate bending approximated as flexure of discrete beams
An alternate method of analysis using Plate Theory
was proposed by Galai for identical flange pairs
Finite Element Analysis using ABAQUS provides
deeper analysis into the behavior of the joint
The primary goal of this project is to determine the
agreement between the three methods selected to analyze
bolted flange joints with contact outside the bolt circle.
Shortcomings and strengths of each analysis method will be
discussed.
Design equations exist in Appendix Y of ASME
BPVC to determine joint separation and flange
stresses
Plate method proposed by Galai for identical flange
pairs will be adapted for a flange-cover joint
Symmetry will be exploited for FEA analysis
Contact Defined to
Govern Joint Behavior
Cylindrical Symmetry
Boundary Conditions
Fluid
Pressure
1/8 (45° Segment) ABAQUS Model
(8 bolts)
Configuration Variables:
◦ Pipe Size (4 & 16 NPS)
◦ Thickness of cover plate
(t=minimum thickness
required by ASME B16.5)
◦ Bolt Preload (0, Equal to
Pressure Load, & 80%YS)
Results to be Investigated
◦ Separation of flange-cover
joint due to pressure
◦ Additional loading of
fasteners due to prying
effects
◦ Location of cover/flange
contact
Nominal Pipe
Size
Cover Thickness
Preload
4
4
4
4
4
4
4
4
4
16
16
16
16
16
16
16
16
16
0.5t
0.5t
0.5t
1t
1t
1t
2t
2t
2t
0.5t
0.5t
0.5t
1t
1t
1t
2t
2t
2t
0
Equal
80%YS
0
Equal
80%YS
0
Equal
80%YS
0
Equal
80%YS
0
Equal
80%YS
0
Equal
80%YS
ASME Boiler and Pressure Vessel Code
Galai, Hichem, and Bouzid, A.H, Analytical Modeling of Flat
Face Flanges with Metal to Metal Contact Beyond the Bolt
Circle, Journal of Pressure Vessel Technology, ASME, Vol 132.
December 2010
Schneider, R. W, and Waters, E. O, The Background of ASME
Code Case 1828: A Simplifying Model of Analyzing Part B
Flanges, Journal of Pressure Vessel Technology, ASME, Vol.
100, No. 2, May 1978