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NX 7.5 second moment of inertia value issue - straight extrusion

NX 7.5 second moment of inertia value issue - straight extrusion

NX 7.5 second moment of inertia value issue - straight extrusion

(OP)
HI,

I need to calculate second moment of inertia for a straight extruded part. I believe the function path in NX 7.5 for analyzing this is Analyze--> Section Inertia. I have set the values to solid prior to exporting the cross sectional results. My problem is that my results do not match what my customer gets from ProE WF3 or what my PE gets from Inventor 2012. Their results are exact matches. This is what I get from NX 7.5:

Info Analysis - Section Inertia Analysis
The mass properties are for solid sections
 
Sect#  CG-XC     CG-YC     CG-ZC     CG-X      CG-Y      CG-Z      SL        SA
1      11.14359650197 6.34291466221 0.00000000045 52.81806056233 -19.30579382280 0.00000000045 736.81068688015 960.02349323938
 
Sect#  Max-MI             Max-X          Max-Y         Max-Z         Min-MI             Min-X          Min-Y          Min-Z        Max-RL         Min-RL
1      1569244.57808 0.22979284045 0.97323956479 0.00000000000 2.12969542668e+005 -0.97323956479 0.22979284045 0.00000000000 84.55506213603 31.14964085635
 
Sect#: Number of Section
 
CG-XC, CG-YC, CG-ZC: Center of Gravity (WCS) [mm]
CG-X, CG-Y, CG-Z: Center of Gravity (Absolute) [mm]
 
Max-MI: Maximum Principal Moments of Inertia [mm^4]
Max-X, Max-Y, Max-Z: Maximum principal Direction
 
Min-MI: Minimum Principal Moments of Inertia [mm^4]
Min-X, Min-Y, Min-Z: Minimum principal Direction
 
Max-RL: Equivalent rectangle section length in Max principal direction [mm]
Min-RL: Equivalent rectangle section length in Min principal direction [mm]
 
SL: Section Length [mm]
SA: Section Area [mm^2]
----------------------------

The attached jpg shows the ProE and Inventor output.

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Wiki description: The second moment of area, also known as the area moment of inertia, moment of inertia of plane area, or second moment of inertia is a property of a cross section that can be used to predict the resistance of beams to bending and deflection, around an axis that lies in the cross-sectional plane.
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Thanks for the help!

RE: NX 7.5 second moment of inertia value issue - straight extrusion

Your CG-X and CG-Y match, and
Ixx = Min-MI
Iyy = Max-MI

The problem seems to be one of semantics.

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