Defining Line Fasteners

You can create a line fastener that joins multiple bodies with a continuous line of connections. You can model these connections with either solid or shell elements.

With an incompatible mesh type, fastener placement is projected on the supports and the corner nodes for the shell elements are created at the projected locations.

With a compatible mesh type, fastener placement matches the existing mesh parts so that the projected node locations match existing nodes. You cannot create compatible meshes between features on a single part or between parts in different finite element model representations.

Note: Multiple layer options are available only for compatible meshes.

This task shows you how to:

See Also
About Line Fasteners
Creating Compatible Meshes for Line Fasteners
Detecting Line Fastener Locations and Applying Line Fasteners
Connections Section
Connection Manager
About Engineering Connections in Simulations
In Other Guides
Creating Simulation Features
Support Selection

Create a Line Fastener with Solid Elements

  1. From the Connections section of the action bar, click Line Fastener .
  2. Choose an engineering connection method and connection.
    OptionDescription
    Default Automatically creates a free engineering connection or selects the existing engineering connection if there is only one.
    Select existing Select an existing engineering connection from a list.

    Note: If you select an existing connection, you must choose a support from the part instances used when the engineering connection was created.

  3. Optional: Enter a descriptive Name.
  4. Edit the supports.

    The following supports are valid for line fastener connections:

    • Support 1: one or more bodies or mesh parts
    • Support 2: one or more bodies or mesh parts

    Tip: To have the app automatically detect the supports when you specify the fastener location, leave Support 1 and Support 2 empty and choose the search option in step 11.

    Tip: You can click to clip the selection area to show only the selected supports—this can make it easier to pick the more detailed Fastener placement geometry you need. After you activate the clipping box, you can click to drag the box edges to resize it.

  5. Optional: To load fastener properties from a saved template file:
    1. Click .
      The Object Selection dialog box appears.
    2. Select one of the following options:

      • Search and select a template from all the template documents stored in the database.
      • Click Import a file to import a document stored on your computer, and click the check mark in the object selection prompt after the document has been imported.

    The parameters are applied to the current fastener definition.
  6. Optional: Click to save the parameters of the current fastener to a reusable template document, and specify a name for the document. For more information, see Template Files.
  7. Specify a material for the fastener by clicking and searching.
  8. Select a material behavior.

    This option is available only if the material has multiple behaviors defined.

  9. Enter the Width of the line fastener.

    For a 3D solid fastener, the width defines the size of the hexahedral elements perpendicular to the fastener gap.

  10. Specify the Fastener placement.
    OptionDescription
    Along lines Select existing edges for the fastener placement.

    The selected edges must be in reasonable proximity of the fastener location—along or between the bodies that the fastener is connecting.

    Specify coordinates Enter or import tabular x-, y-, and z-coordinates to define a polyline for fastener placement.
    Note: Table values are not verified for logical errors such as duplicate entries.
    Line-lineSelect edges on each of the parts to join with the fastener.

    You can also select a geometric set containing points and curves to use the set data for fastener placement.

    Warning: There are no restrictions on the edges that you can select to create the fastener. Selection of an inappropriate edge might cause the connection to fail before or during the simulation.

  11. Optional: If you have not specified the supports, click Search for supports to have the app search for supports closest to the fastener placement.
  12. Select Solid hex for the fastener Construct type.

    The C3D8 element type is used regardless of the global element types assigned to the model.

  13. Specify the fastener Realization options.
    OptionDescription
    Weighting method

    Uniform: Maintains an equal weight factor for all nearest nodes (nodes in the mesh element faces containing the projected location).

    Tied: Weights each node based on the shape of the mesh element face that contains the projected location (available for linear meshes only).
    Maximum projection distance Defines the maximum gap (distance) between the placement geometry and the body you are connecting. The fastener is not created if the placement geometry and the body are farther apart.
    Maximum angle Limit for the angle of inclination between the two surfaces being fastened. The fastener mesh is still created if the angle is exceeded. However, you will get a mesh warning.
    Height Specifies the fastener height, if it is different from the gap.
    Spacing Defines the size of each element along the edge that defines the fastener.
    Number of elements along width Use if more than one element across the fastener width is required.
    Note: When this value is greater than one, the fastener Width entered above represents the combined width of the elements.
    Number of layers Use if more than one element through the gap height is required.
  14. Optional: Click Update Mesh to see the mesh created for the line fastener.

    Review the updated mesh, modify parameters to resolve any mesh errors, and validate or correct any reported warnings.

  15. Click OK.

Create a Line Fastener with Shell Elements and an Incompatible Mesh

  1. From the Connections section of the action bar, click Line Fastener .
  2. Choose an engineering connection method and connection.
    OptionDescription
    Default Automatically creates a free engineering connection or selects the existing engineering connection if there is only one.
    Select existing Select an existing engineering connection from a list.

    Note: If you select an existing connection, you must choose a support from the part instances used when the engineering connection was created.

  3. Optional: Enter a descriptive Name.
  4. Edit the supports.

    The following supports are valid for line fastener connections:

    • Support 1: one or more bodies or mesh parts
    • Support 2: one or more bodies or mesh parts

    Tip: To have the app automatically detect the supports when you specify the fastener location, leave Support 1 and Support 2 empty and choose the search option in step 11.

    Tip: You can click to clip the selection area to show only the selected supports—this can make it easier to pick the more detailed Fastener placement geometry you need. After you activate the clipping box, you can click to drag the box edges to resize it.

  5. Optional: To load fastener properties from a saved template file:
    1. Click .
      The Object Selection dialog box appears.
    2. Select one of the following options:

      • Search and select a template from all the template documents stored in the database.
      • Click Import a file to import a document stored on your computer, and click the check mark in the object selection prompt after the document has been imported.

    The parameters are applied to the current fastener definition.
  6. Optional: Click to save the parameters of the current fastener to a reusable template document, and specify a name for the document. For more information, see Template Files.
  7. Specify a material for the fastener by clicking and searching.
  8. Select a material behavior.

    This option is available only if the material has multiple behaviors defined.

  9. Enter the Width of the line fastener.

    For a 2D shell fastener, the width defines the thickness of the shell elements.

  10. Specify the Fastener placement.
    OptionDescription
    Along lines Select existing edges for the fastener placement.

    The selected edges must be in reasonable proximity of the fastener location—along or between the bodies that the fastener is connecting.

    Specify coordinates Enter or import tabular x-, y-, and z-coordinates to define a polyline for fastener placement.
    Note: Table values are not verified for logical errors such as duplicate entries.
    Line-lineSelect edges on each of the parts to join with the fastener.

    You can also select a geometric set containing points and curves to use the set data for fastener placement.

    Warning: There are no restrictions on the edges that you can select to create the fastener. Selection of an inappropriate edge might cause the connection to fail before or during the simulation.

  11. Optional: If you have not specified the supports, click Search for supports to have the app search for supports closest to the fastener placement.
  12. Select Shell for the fastener Construct type.

    The S4R element type is used regardless of the global element types assigned to the model.

  13. Specify the Mesh type as Incompatible.
  14. Specify the fastener Realization options.
    OptionDescription
    Weighting method

    Uniform: Maintains an equal weight factor for all nearest nodes (nodes in the mesh element faces containing the projected location).

    Tied: Weights each node based on the shape of the mesh element face that contains the projected location (available for linear meshes only).
    Maximum projection distance Defines the maximum gap (distance) between the placement geometry and the body you are connecting. The fastener is not created if the placement geometry and the body are farther apart.
    Maximum angle Limit for the angle of inclination between the two surfaces being fastened. The fastener mesh is still created if the angle is exceeded. However, you will get a mesh warning.
    Height Specifies the fastener height, if it is different from the gap.
    Spacing Defines the size of each element along the edge that defines the fastener.
  15. Optional: Click Update Mesh to see the mesh created for the line fastener.

    Review the updated mesh, modify parameters to resolve any mesh errors, and validate or correct any reported warnings.

  16. Click OK.

Create a Line Fastener with Shell Elements and a Compatible Mesh

  1. From the Connections section of the action bar, click Line Fastener .
  2. Choose an engineering connection method and connection.
    OptionDescription
    Default Automatically creates a free engineering connection or selects the existing engineering connection if there is only one.
    Select existing Select an existing engineering connection from a list.

    Note: If you select an existing connection, you must choose a support from the part instances used when the engineering connection was created.

  3. Optional: Enter a descriptive Name.
  4. Edit the supports.

    The following supports are valid for line fastener connections:

    • Support 1: one or more bodies or mesh parts
    • Support 2: one or more bodies or mesh parts

    You can use the context menu in the Feature Manager to reuse supports from an existing connection. However, you can reuse supports only if they meet the requirements of the current connection type.

    Tip: To have the app automatically detect the supports when you specify the fastener location, leave Support 1 and Support 2 empty and choose the search option in step 11.

    Tip: You can click to clip the selection area to show only the selected supports—this can make it easier to pick the more detailed Fastener placement geometry you need. After you activate the clipping box, you can click to drag the box edges to resize it.

  5. Optional: To load fastener properties from a saved template file:
    1. Click .
      The Object Selection dialog box appears.
    2. Select one of the following options:

      • Search and select a template from all the template documents stored in the database.
      • Click Import a file to import a document stored on your computer, and click the check mark in the object selection prompt after the document has been imported.

    The parameters are applied to the current fastener definition.
  6. Optional: Click to save the parameters of the current fastener to a reusable template document, and specify a name for the document. For more information, see Template Files.
  7. Specify a material for the fastener by clicking and searching.
  8. Select a material behavior.

    This option is available only if the material has multiple behaviors defined.

  9. Enter the Width of the line fastener.

    For a 2D shell fastener, the width defines the thickness of the shell elements.

  10. Specify the Fastener placement.
    OptionDescription
    Along lines Select existing lines for the fastener placement.

    The selected edges must be in reasonable proximity of the fastener location—along or between the bodies that the fastener is connecting.

    Specify coordinates Enter or import tabular x-, y-, and z-coordinates to define a polyline for the fastener placement.
    Note: Table values are not verified for logical errors such as duplicate entries.
    Line-lineSelect edges on each of the parts to join with the fastener.
    Support boundary Select existing lines for the fastener placement. This method offers additional options for modeling welds on midsurfaced parts.

    The selected line cannot be an edge from a midsurface support and can be used in only one line fastener definition.

    You can also select a geometric set containing points and curves to use the set data for fastener placement.

    Warning: There are no restrictions on the edges that you can select to create the fastener. Selection of an inappropriate edge might cause the connection to fail before or during the simulation.

  11. Optional: If you have not specified the supports, click Search for supports to have the app search for supports closest to the fastener placement.
  12. Select Shell for the fastener Construct type.

    Regardless of the global element types assigned to the model, the connection generates either S4R or S8R elements for compatible meshes:

    • If both the supports have linear mesh, the connection generates S4R elements.
    • If both the supports have quadratic mesh, the connection generates S8R elements.
    • If the supports have a mixture of linear and quadratic meshes, the connection generates S4R elements and posts a warning.

  13. If you are using the Support boundary placement method, see Defining Line Fasteners Using the Support Boundary Method.
  14. Select Compatible for the Mesh type.
  15. Specify the fastener Realization options.
    OptionDescription
    Maximum projection distance Defines the maximum gap (distance) between the placement geometry and the body you are connecting. The fastener is not created if the placement geometry and the body are farther apart.
    Maximum angle Limit for the angle of inclination between the two surfaces being fastened. The fastener mesh is still created if the angle is exceeded. However, you will get a mesh warning.
    Number of layers Controls the number of elements through the gap height.
    Layer distribution

    Uniform: Layers are the same height.

    Arithmetic: Layers vary by a constant value.

    Geometric: Layers vary by a constant ratio.

    Layer size ratio

    (For multiple layers with nonuniform distribution.)

    		 Controls the ratio of the largest to smallest layer size.
    Symmetric layers Makes the layer distribution symmetrical.
  16. Optional: Click Update Mesh to see the mesh created for the line fastener.

    Review the updated mesh, modify parameters to resolve any mesh errors, and validate or correct any reported warnings.

  17. Click OK.