Node Locations on Bends - CAESAR II - Installation & Upgrade

CAESAR II Quick Reference

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English (United States)
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CAESAR II
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Installation & Upgrade
CAESAR II Version
12

Bends are defined by the element entering the bend and the element leaving the bend. The actual bend curvature is always physically at the TO end of the element entering the bend.

  • The element leaving a bend must appear immediately after the element defining (entering) the bend.

  • The default bend radius is 1.5 times the pipe nominal OD.

  • For stress and displacement output, the TO node of the element entering the bend is located geometrically at the FAR point on the bend. The FAR point is at the weld line of the bend and adjacent to the straight element leaving the bend.

  • The NEAR point on the bend is at the weld line of the bend and adjacent to the straight element entering the bend.

  • The FROM point on the element is located at the NEAR point of the bend if the total length of the element as specified in the DX, DY and DZ fields is equal to:

    Radius * tan( Beta / 2 )

    where Beta is the bend angle and Radius is the bend radius of curvature to the bend centerline.

  • Nodes defined in the Angle # and Node # fields are placed at the given angle on the bend curvature. The angle starts with zero degrees at the NEAR point on the bend and goes to “Beta” degrees at the FAR point of the bend.

  • Angles are always entered in degrees.

    By default, nodes on the bend curvature cannot be specified within five (5) degrees of one another or within five degrees of the nearest end point. This and other bend settings may be changed in the Configuration Editor. Click Configure or Tools > Configure/Setup. For more information, see Configuration Options and Geometry Directives.

  • When the FROM node on the element entering the bend is not at the bend NEAR point, a node may be placed at the NEAR point of the bend by entering an Angle # equal to 0.0 degrees. For more information, see the graphic below.

    When defining a bend element for the first time in the pipe spreadsheet, nodes are automatically placed at the near and midpoint of the bend. The generated midpoint node number is one less than the TO node number on the element, and the generated near point node number is two less than the TO node number on the element. A near point should always be included in the model in tight, highly formed piping systems. The top-left figure below shows the points on the bend as they would be input. The top-right figure shows the actual geometric location of the points on the bend. The bottom-left figure shows the same geometry except that two nodes are defined on the bend curvature at angles of zero and forty-five degrees.

For an animated tutorial on modeling bends, click Help > Animated Tutorials in the main CAESAR II window.