Figure 1.1.1-8 Normal stress distribution in the gasket contact surface along the line z = 0 for the models with and without superelements.
Sample listings
Listing 1.1.1-1
*ELEMENT, TYPE=CAX8R, INPUT=boltpipeflange_axi_element.inp
*ELSET, ELSET=PID1, GENERATE
** Contact Between Gasket and Hub
**
*CONTACT PAIR, INTERACTION=ROUGH, SMALL SLIDING, ADJUST=.1 HUB_BOT,GASKET
*SURFACE INTERACTION,NAME=ROUGH
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
**
** Contact Between Bolt and Hub
**
*ELEMENT, TYPE=CAX8R, INPUT=boltpipeflange_axi_element.inp
*ELSET, ELSET=PID1, GENERATE
** Contact Between Gasket and Hub
**
*CONTACT PAIR, INTERACTION=ROUGH, SMALL SLIDING, ADJUST=.1 HUB_BOT,GASKET
*SURFACE INTERACTION,NAME=ROUGH
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
**
** Contact Between Bolt and Hub
**
** Note: Areas associated with contact nodes are determined
** by first calculating out-of-plane surface areas represented
** by the contact faces of bottom-side bolthead elements, and
** then assigning ratios of these areas to the relative contact
** nodes which lie on the faces.
**
** Note: Areas associated with contact nodes are determined
** by first calculating out-of-plane surface areas represented
** by the contact faces of bottom-side bolthead elements, and
** then assigning ratios of these areas to the relative contact
** nodes which lie on the faces.
**
577,580
*CONTACT PAIR, INTERACTION=BLT_HUB1, SMALL SLIDING, HCRIT=1.1 NBOLT1,HUB_BOLT
NBOLT1B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB1 12.899,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB2, SMALL SLIDING, HCRIT=1.1 NBOLT2,HUB_BOLT
NBOLT2B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB2 25.799,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB3, SMALL SLIDING, HCRIT=1.1 NBOLT3,HUB_BOLT
NBOLT3B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB3 36.012,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB4, SMALL SLIDING, HCRIT=1.1 NBOLT4,HUB_BOLT
NBOLT4B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB4 46.226,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB5, SMALL SLIDING, HCRIT=1.1 NBOLT5,HUB_BOLT
NBOLT5B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB5 52.378,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB6, SMALL SLIDING, HCRIT=1.1 577,580
*CONTACT PAIR, INTERACTION=BLT_HUB1, SMALL SLIDING, HCRIT=1.1 NBOLT1,HUB_BOLT
NBOLT1B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB1 12.899,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB2, SMALL SLIDING, HCRIT=1.1 NBOLT2,HUB_BOLT
NBOLT2B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB2 25.799,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB3, SMALL SLIDING, HCRIT=1.1 NBOLT3,HUB_BOLT
NBOLT3B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB3 36.012,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB4, SMALL SLIDING, HCRIT=1.1 NBOLT4,HUB_BOLT
NBOLT4B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB4 46.226,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB5, SMALL SLIDING, HCRIT=1.1 NBOLT5,HUB_BOLT
NBOLT5B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB5 52.378,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB6, SMALL SLIDING, HCRIT=1.1
NBOLT6,HUB_BOLT NBOLT6B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB6 58.529,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB7, SMALL SLIDING, HCRIT=1.1 NBOLT7,HUB_BOLT
NBOLT7B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB7 63.107,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB8, SMALL SLIDING, HCRIT=1.1 NBOLT8,HUB_BOLT
NBOLT8B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB8 67.685,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB9, SMALL SLIDING, HCRIT=1.1 NBOLT9,HUB_BOLT
NBOLT9B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB9 33.842,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
**
** Mesh Refinement
**
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB7, SMALL SLIDING, HCRIT=1.1 NBOLT7,HUB_BOLT
NBOLT7B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB7 63.107,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB8, SMALL SLIDING, HCRIT=1.1 NBOLT8,HUB_BOLT
NBOLT8B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB8 67.685,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
*CONTACT PAIR, INTERACTION=BLT_HUB9, SMALL SLIDING, HCRIT=1.1 NBOLT9,HUB_BOLT
NBOLT9B,HUBBOLTB
*SURFACE INTERACTION,NAME=BLT_HUB9 33.842,
*FRICTION,ROUGH
*SURFACE BEHAVIOR, NO SEPARATION
**
** Mesh Refinement
**
QUADR, 1934, 202, 218, 228
524, 2116, 2128, 5009, 2118, 2121, 2129, 2122, 2117
547, 2196, 2210, 2212, 2198, 2203, 2211, 2204, 2197
*SOLID SECTION, ELSET=PID2, MATERIAL=MID2 1.,
**
** Note: Thicknesses of plane stress bolthead elements are
** determined by first calculating the areas which the 3-D
** volumes represented by the 2-D elements project onto the
** 1-3 plane, and then dividing the areas by the respective
** element widths.
**
** bolthead_1
*SOLID SECTION, ELSET=PID7, MATERIAL=MID1 51.5976,
** bolthead_12
*SOLID SECTION, ELSET=PID18, MATERIAL=MID1 51.5976,
** bolthead_2
*SOLID SECTION, ELSET=PID8, MATERIAL=MID1 92.4522,
** bolthead_11
*SOLID SECTION, ELSET=PID17, MATERIAL=MID1 92.4522,
*SOLID SECTION, ELSET=PID2, MATERIAL=MID2 1.,
**
** Note: Thicknesses of plane stress bolthead elements are
** determined by first calculating the areas which the 3-D
** volumes represented by the 2-D elements project onto the
** 1-3 plane, and then dividing the areas by the respective
** element widths.
**
** bolthead_1
*SOLID SECTION, ELSET=PID7, MATERIAL=MID1 51.5976,
** bolthead_12
*SOLID SECTION, ELSET=PID18, MATERIAL=MID1 51.5976,
** bolthead_2
*SOLID SECTION, ELSET=PID8, MATERIAL=MID1 92.4522,
** bolthead_11
*SOLID SECTION, ELSET=PID17, MATERIAL=MID1 92.4522,
** bolthead_3
*SOLID SECTION, ELSET=PID9, MATERIAL=MID1 117.058,
** bolthead_10
*SOLID SECTION, ELSET=PID16, MATERIAL=MID1 117.058,
** bolthead_4
*SOLID SECTION, ELSET=PID10, MATERIAL=MID1 135.37,
** bolthead_9
*SOLID SECTION, ELSET=PID15, MATERIAL=MID1 135.37,
** bolthead_5
*SOLID SECTION, ELSET=PID11, MATERIAL=MID1 164.887,
** bolthead_8
*SOLID SECTION, ELSET=PID14, MATERIAL=MID1 164.887,
** bolthead_6
*SOLID SECTION, ELSET=PID12, MATERIAL=MID1 188.382,
** bolthead_7
*SOLID SECTION, ELSET=PID13, MATERIAL=MID1 188.382,
** gasket_elements
*SOLID SECTION, ELSET=PID3, MATERIAL=MID3 1.,
** bolttrunk_1
*SOLID SECTION, ELSET=PID19, MATERIAL=MID1 78.6157,
** bolttrunk_4
*SOLID SECTION, ELSET=PID22, MATERIAL=MID1 78.6157,
** bolttrunk_2
*SOLID SECTION, ELSET=PID20, MATERIAL=MID1 122.446,
** bolttrunk_3
*SOLID SECTION, ELSET=PID21, MATERIAL=MID1 122.446,
** hole_elements
*SOLID SECTION, ELSET=PID1, MATERIAL=MID4,ORIENT=RECT 1.,
**local orientation matching global system
** bolthead_3
*SOLID SECTION, ELSET=PID9, MATERIAL=MID1 117.058,
** bolthead_10
*SOLID SECTION, ELSET=PID16, MATERIAL=MID1 117.058,
** bolthead_4
*SOLID SECTION, ELSET=PID10, MATERIAL=MID1 135.37,
** bolthead_9
*SOLID SECTION, ELSET=PID15, MATERIAL=MID1 135.37,
** bolthead_5
*SOLID SECTION, ELSET=PID11, MATERIAL=MID1 164.887,
** bolthead_8
*SOLID SECTION, ELSET=PID14, MATERIAL=MID1 164.887,
** bolthead_6
*SOLID SECTION, ELSET=PID12, MATERIAL=MID1 188.382,
** bolthead_7
*SOLID SECTION, ELSET=PID13, MATERIAL=MID1 188.382,
** gasket_elements
*SOLID SECTION, ELSET=PID3, MATERIAL=MID3 1.,
** bolttrunk_1
*SOLID SECTION, ELSET=PID19, MATERIAL=MID1 78.6157,
** bolttrunk_4
*SOLID SECTION, ELSET=PID22, MATERIAL=MID1 78.6157,
** bolttrunk_2
*SOLID SECTION, ELSET=PID20, MATERIAL=MID1 122.446,
** bolttrunk_3
*SOLID SECTION, ELSET=PID21, MATERIAL=MID1 122.446,
** hole_elements
*SOLID SECTION, ELSET=PID1, MATERIAL=MID4,ORIENT=RECT 1.,
**local orientation matching global system
*ORIENTATION,NAME=RECT
** BOLTS ASSUME PLANE STRESS CONDITIONS.
** THERE ARE 8 BOLTS SO A=8* BOLT CROSS-SECTION AREA
** flange_material
155.29E3, 155.29E3, 155.29E-3, 0.3, 0.0, 0.0, 59.728E3, 77.65E-3, 77.65E-3,
** BOLTS ASSUME PLANE STRESS CONDITIONS.
** THERE ARE 8 BOLTS SO A=8* BOLT CROSS-SECTION AREA
** flange_material
155.29E3, 155.29E3, 155.29E-3, 0.3, 0.0, 0.0, 59.728E3, 77.65E-3, 77.65E-3,
ESECT,S2
*NODE FILE, NSET=NOUT, FREQUENCY=1 U, RF
1.1.2 Elastic-plastic collapse of a thin-walled elbow under in-plane bending and internal pressure
Product: ABAQUS/Standard
Elbows are used in piping systems because they ovalize more readily than straight pipes and, thus, provide flexibility in response to thermal expansion and other loadings that impose significant displacements on the system. Ovalization is the bending of the pipe wall into an oval, noncircular configuration. The elbow is, thus, behaving as a shell rather than as a beam. Straight pipe runs do not ovalize easily, so they behave essentially as beams. Thus, even under pure bending, complex
interaction occurs between an elbow and the adjacent straight pipe segments; the elbow causes some ovalization in the straight pipe runs, which in turn tend to stiffen the elbow. This interaction can create significant axial gradients of bending strain in the elbow, especially in cases where the elbow is very flexible. This example provides verification of shell and elbow element modeling of such effects, through an analysis of a test elbow for which experimental results have been reported by Sobel and Newman (1979). An analysis is also included with elements of type ELBOW31B (which includes ESECT,S2
*NODE FILE, NSET=NOUT, FREQUENCY=1 U, RF
1.1.2 Elastic-plastic collapse of a thin-walled elbow under in-plane bending and internal pressure
Product: ABAQUS/Standard
Elbows are used in piping systems because they ovalize more readily than straight pipes and, thus, provide flexibility in response to thermal expansion and other loadings that impose significant displacements on the system. Ovalization is the bending of the pipe wall into an oval, noncircular configuration. The elbow is, thus, behaving as a shell rather than as a beam. Straight pipe runs do not ovalize easily, so they behave essentially as beams. Thus, even under pure bending, complex
interaction occurs between an elbow and the adjacent straight pipe segments; the elbow causes some ovalization in the straight pipe runs, which in turn tend to stiffen the elbow. This interaction can create significant axial gradients of bending strain in the elbow, especially in cases where the elbow is very flexible. This example provides verification of shell and elbow element modeling of such effects, through an analysis of a test elbow for which experimental results have been reported by Sobel and Newman (1979). An analysis is also included with elements of type ELBOW31B (which includes
ovalization but neglects axial gradients of strain) for the elbow itself, and beam elements for the straight pipe segments. This provides a comparative solution in which the interaction between the elbow and the adjacent straight pipes is neglected. The analyses predict the response up to quite large rotations across the elbow, so as to investigate possible collapse of the pipe and, particularly, the effect of internal pressure on that collapse.