Seam Panel

Use the Seam panel to create connectors that represent line connectors such as seam welds. These connectors can later be realized as standard or custom weld representations.

Location: Connectors module

When the Seam panel is active, only seam-type connectors display in the modeling window; graphics for other connector types are suppressed until you exit the panel.

Subpanel Organization

The Seam panel is arranged into several subpanels. You can move freely between subpanels. Your work on one subpanel will not be lost if you switch to a different subpanel. However, similar settings will not be shared between subpanels, so for example changing the tolerance in one subpanel does not change it in any of the others. In most cases one or more green command buttons on the right edge of the subpanel must be used to execute the function once all options have been specified.
Seam Subpanel
Create and realize seam connectors.
Create Subpanel
Create, but do not realize seam connectors.
Realize Subpanel
Realize existing seam connectors (no creation or editing possible).
Edit Subpanel
Edit existing seam connectors.
Partition Subpanel
Partition (separate into sections of connections that passed or failed valid projections) an existing seam connector.
The Seam, Create and Realize subpanels use the same set of options.
  • The first column contains everything related to connector creation and link detection.
  • The second column contains everything related to realization type, post script and property assignment.
  • The third column contains everything related to the final connection to the link entities.

Connector Creation and Link Detection Options

Option Action
location Specify the location of the connector to be created.
lines/line list
Select lines and specify spacing or density.
If you select several lines, HyperMesh determines whether lines share the same start points and end points or not. This means, HyperMesh is able to determine if certain groups of lines can principally be combined into one line.

How this information is used during connector creation depends on the line combine, group CE, and do not group CE options.

node list
Select a node list and specify spacing or density.
The selected nodes are used to internally create a smoothed line, which is used exactly as a real line. The connector will not remember the position of the selected nodes, unless you select the preserve nodes checkbox.

You can only create one seam connector at a time using a node list.

When you are selecting a node list, and the first and last node belong to the same element, HyperMesh will create the connector as a closed loop.

spacing/density
spacing
Distance between each weld location on the line.
density
Number of weld location on the line.
retain nodes Retain the position of the nodes when you create and realize a connector.
Note: Only available if location is set to nodelist.
connectors Select the connector(s) to be realized.
line combine

Create one seam connector for each sequence of lines and each single line. With this option enabled, a sequence of lines will be internally treated as on line.

This option is preferred for continuous seams together with realization types where the body element is positioned between the weld points of all quad and hexa seam realizations.

With this option, neither the vertices nor the start point and end point of the initial lines are considered, and there likely will not be any weld points at the exact positions.
Note: Default setting when location is set to linelist.


Figure 1.


Figure 2.
group CE
Create one seam connector from each selected line, and group those seams which form a sequence of seam connectors together. Each group of connectors is then treated as a single connector entity. Each connector in the group has the same display mode, same realization state, and so on. Furthermore the start points and end points of two sequenced connectors in that group are treated as being one point. This fact allows this option also to be used together with realization types where the body element is positioned between the weld points, such as for all quad and hexa seam realizations. For hexa seams and for use of quad transition, the vertex angle has to be quite small to prevent bad hexa elements or imprint conflicts.
Note: The selected lines need to be longer than half the spacing length, otherwise the lines are ignored.


Figure 3.
do not group CE
Create one seam connector from each selected line. Even those seams which form a sequence of seam connectors are not grouped together. The start- and end- points of two sequenced connectors in that group are treated as being different points. This fact makes the use of quad transition impossible for sequenced seam connectors, because the imprint patterns will always conflict each other.
Note: The selected lines need to be longer than half the spacing length, otherwise the lines are ignored.


Figure 4.
connect what
Select the entities to become link candidates. Link candidates are certain entities of a chosen link type, which are supposed to be connected during the realization. Entities outside the tolerance are not taken into account.
comps
Select components to be added as link entities.
Choose to connect to either the geometry or elements of the selected components.
assems
Select assemblies to be added as link entities.
Choose to connect to either the geometry or elements of the selected assemblies.
surfs
Select surfaces to be added as link entities.
Choose to connect to either the geometric surfaces or elements associated to the selected surfaces.
Note: Connectors can be created with different types of entities; for example, a connector can be defined by selecting a component on one side and an assembly on the other side. This can be done by creating a connector to specify one of the entity types and selecting that entity. Add the second entity by updating the connector via the add links functionality in the Connector browser or the Add Links panel.
num layers

Define how many thicknesses (layers) have to be connected at the connector position.

This number is predefined as 2. There is not a field in the this panel where you can set the number of layers; however, you can find the number of layers in the Connector browser.

When link detection is performed the valid connector links are established with respect to the given tolerance and the selected link candidates. By default the links are reduced to the minimum needed. The number of links is typically higher than the number of layers, because a valid pair of projections need to be found per test point.

tolerance

Define a distance from the connector location (per each test point).

Only entities within this tolerance can be taken into account for the link detection and the final realization. Thus, the tolerance is used twice: first for the link determination and again for the realization. In the second step the tolerance is used to verify whether adequate link candidates are available to be connected.

During pure connector creation on the Create subpanel, the tolerance is used for the link determination, but not necessarily stored on the connector unless the checkbox in front of the tolerance field is marked. In this way different tolerances can be used.

The tolerance used during the realization process is always written to the connector.

connect when
Select when to perform link detection.
now
Add link entity information now, directly together with the connector creation.
at fe-realize
Create a connector without any specific information regarding its links.
Links are determined when performing the final realization with respect to the connector position.
Using this option defines the re-connect rule at-fe-realize for all created links.
reconnect rule
While realizing the connector, HyperMesh looks for link entities based on the re-connect rule.
Tip: This option is useful in situations where the parts to be connected have been changed/replaced.
none
No re-connect rule is defined. If the link entity is not currently in the model, the connector with this re-connect rule will fail to realize.
If no re-connect rule is defined for a link, this link disappears from the connector when the linked entity is deleted.
use id
Use the selected link entity’s IDs to re-connect. If the link entity is not currently in the model, the connector with this re-connect rule will search for entities with the same ID.
use name
Use the selected link entity’s names to re-connect. If the link entity is not currently in the model, connectors using this re-connect rule search for entities with the same name.
reverse direction During the first realization of a seam its direction is determined. Even though this direction is only important for realization types which use angle information like seam-quad (angled), every seam gets this direction. Therefore the reverse direction checkbox only appears for angled seams.
The direction can only be reversed during the next realization if the checkbox is enabled.
Note: Normally this option is only needed for T-welds, because in that case there isn’t any indication for the probable direction.
For this reason, if an angled T-weld should be realized together with quad transition, it might be useful to skip the imprint in the first step and review the assumed direction. Rerealize all wrong directed seams with the checkbox enabled. If all directions are correct, uncheck the option and rerealize with active imprint. This procedure prevents the mesh from being interfered more often than necessary.

Post Script and Property Assignment Options

Option Action
type
Select the realization type which should be used. The realization type is a description of the FE representation.
Note: The available realization types are dependant on the configuration file loaded under fe file on the general connector Options panel.
post script treatment
Choose whether or not a post script has to be used for the specific realization type. These scripts are used to automatically create materials, properties, and/or contacts necessary for realizing the connectors.
default post script
Default for any realization type having a post script defined in its FE configuration.
user post script
Select your own .tcl file which should be used. Such a file can perform a special treatment on the FE representation.
no/skip post script
Default for all realization types without any post script defined. No post script is used.
elems to current comp / connector comp
Select which component the FE representations are stored in once they have been realized.
current comp
Store newly-realized connectors in the current component.
connector comp
Store newly created FE representations in the same component that the connector was originally created in.
Note: Only available in the realize subpanel when post script treatment is set to no/skip post script.
property treatment
Select a property treatment.
property
Click property= and select a property to assign to all newly created elements.
no property
No property gets assigned.
Note: Only available when post script treatment is set to no/skip post script.
direct property assignment
Directly assign the property, otherwise assign the property to the destination components.
Note: Only available when property treatment is set to property =, and the solver interface is Nastran, OptiStruct, Radioss or Abaqus.

Quad Realization Options

Exclusive options available for seam realization types with a quad row representing the connection. Not all of these settings have to be defined for all quad realization types.


Figure 5.
Option Action
weld angle Define the distance between the normal projection and the quad direction.

Principally it is allowed to define weld angles between 0.0 and 90.0. If the value is set to 0.0 an internal thickness-based calculation is used. If the value is set to 0.0 and no thickness is defined the connector will fail.

If the angle is created in the wrong direction, the seam can be reverted by enabling the reverse direction checkbox and performing a rerealization.

cap angle Depending on the seam-quad type, the cap angle is measured differently.
  • Measured between the normals of the cap element and the second-to-last element of the seam.
  • Measured between the edge normals of the cap element and the second-to-last element of the seam in the plane of the opposite link.

Cap angles are created by default. Clear this checkbox to remove cap angles and runoff angles.

Cap angles between 0.0 and 45.0 are permitted, but be aware that larger values can lead to bad elements. The recommended value is 10.0 or smaller. Cap angles between 45.0 and 90.0 are permitted, but be aware that smaller values lead to bad elements. The recommended value is 75.0 and higher.
Note: Only available for seam-quad (angled + capped + L) and seam-quad (angled + capped + T).
runoff angle Depending on the seam-quad type, the runoff angle is measured differently.
  • Measured between the normals of the last and the second-to-last last element of the seam.
  • Measured between the edge normals of the last and the second-to-last element of the seam in the plane of the opposite link.
Clearing the cap angles checkbox removes runoff angles, which are created by default.
height Define the distance between the projection point and the start-point of the angled quads.
Note: Only available for T-seams.
The height needs to be chosen in an extent to bridge the gap between the links. Also, the height strongly influences the quad length, especially in cases of very large weld angles.

Hexa Realization Options

Exclusive options available for seam realization types with hexa row(s) representing the connection.


Figure 6.
Option Action
width Define the width of the continuous hexa weld in the direction perpendicular to the seam direction.
Note: Only available for hexa (adhesive) and hexa (RBE2-RBE3).
strips Define the number of hexa elements required along the width.
coats Defines the number of hexa elements required along the thickness.
thickness
Select a method for defining the thickness of a hexa weld.
shell gap
Project the hexa to touch the shell elements.
The position is independent from any thickness.
(T1+T2)/2
Hexa size (thickness) depends on the shell thickness of the connected parts.
mid thickness
Calculate the hexa size (thickness) as the air gap between the two connected parts.
If there is no gap, or even a penetration, the hexa size is always modeled with 1.0.
const. thickness
Specify the hexa size (thickness).
maintain gaps
Calculate the hexa size (thickness) as the gap distance reduced by two times the specified value for maintain gaps.
The position is independent from any thickness.
Note:
  • The exact hexa position is also influenced by the consider shell thickness and offset for solid positioning option.
  • Only available for hexa (adhesive) and hexa (RBE2-RBE3).


Figure 7.
thickness dependent / angle, D and H / H1, H2 and D Hexa (tapered T) enables you to create tapered seam hexas for T-connections.
Select a method to define how hexas are positioned and located, and assign appropriate values to any corresponding inputs.
thickness dependent
tmin
min(t1;t2)
d
factor_a * tmin
h1
factor_b + 2.5 * t2
h2
factor_b + 2.5 * 211


Figure 8.
angle, D and H
angle α
angle to the base sheet
d
thickness of hexa
h
height from the basesheet


Figure 9.
H1, H2 and D
h1
distance on T sheet
h2
distance on basesheet
d
thickness of hexa


Figure 10.
discontinuity By default, the length and pattern of a hexa weld is defined by test points along the seam connector. To ignore the predefined test points, and define a specific element length, weld length, and break length to realize the connector with, select the discontinuity checkbox. With this option, a hexa adhesive seam with alternating weld pieces and gaps is created.
When discontinuity is enabled, you must define the following inputs:
elem length
Specify the length of a hexa along the seam connector.
weld length/scale (elem)
Specify the length of the hexa weld.
break length/scale (elem)
Specify the amount of space to place in between the hexa welds.
If the defined lengths do not fit exactly to the seam connector length, mathematical correct rounding is used. To guarantee, that the rounded lengths are not too far away from the expected values, minimum and maximum deviations are defined in the seam options.
Note: Only available for hexa (adhesive) realizations.
hexa position to edge Select a location to create the hexa from the edge.
midpoint
Position the hexa to the exact location of the connector after snapping.
offset from edge
Specify a distance from the edge to offset the hexa.
positive edge
Position the hexa to the outside of the edge.
The positive side is normally the side with the larger angle.
negative edge
Position the hexa to the inside of the edge.
The negative side is normally the side with the smaller angle.
The angle that is close to 90° (88° to 90°) the element normal of the first found shell element at the free edge decides which side is the positive and the negative side.
Note: Only available for hexa (adhesive) and hexa (RBE2-RBE3).
edge details
In many cases, the connector position is not very precise. To create the requested result, an automatic edge snapping can be enabaled. In the first step the connector snaps to, for example, the closest free edge, and then from there the projection and FE creation starts. Select how many element rows away from the free edge to snap the connector to for L and T connections.
maximum 1 element row
maximum 2 element rows
no
Do not snap the connector.

Penta Realization Options



Figure 11.
Option Action
width Specify the length of a penta.
Note: Only available for penta (mig), penta (mig + L), penta (mig + T), and penta (mig + B).
fitted/equilateral/equilateral-fitted
Select the size and shape of a penta.
fitted
The length of one penta edge is the exact projection distance, and the length of the other penta edge is defined by the width value; the penta has an right-angle.


Figure 12. Example: Fitted
equilateral
Create an equilateral penta; leg lengths are defined by the width value.


Figure 13. Example: Equilateral
equilateral/fitted
Combination of fitted and equilateral; you do not need to define a width when you select this option.


Figure 14. Example: Equilateral/Fitted
Note: Only available for penta (mig) and penta (mig + L).
right-angled
Create a right-angled penta that is oriented around the bisector. Clear this checkbox to create an angle adapted penta.


Figure 15. Right-Angled T-weld Penta Created on Both Sides of the Normal


Figure 16. Angle Adapted T-weld Penta Created on Both Sides of the Normal
Note: Only available for penta (mig) and penta (mig + T).
both sides/positive sides/negative sides
Select which side of the normal to create the penta on.
(mig + L)
The negative side is the side where the links are fairly parallel to each other. The angle that is close to 90° (88° to 90°) the element normal of the first found shell element at the free edge decides which side is the positive and the negative side.




Figure 17. Example: (mig + L)
(mig + T)
The positive side is normally the side with the obtuse angle. The angle that is close to 90° (88° to 92°) the element normal of the first found shell element at the free edge decides which side is the positive and negative side.




Figure 18. Example: (mig + T)
(mig + B)
The positive side is the side where the element normal of the first link points to.




Figure 19. Example: (mig + B)
Note: Only available for penta (mig), penta (mig + L), penta (mig + T), and penta (mig + B).
edge details
In many cases, the connector position is not very precise. To create the requested result, an automatic edge snapping can be enabaled. In the first step the connector snaps to, for example, the closest free edge, and then from there the projection and FE creation starts. Select how many element rows away from the free edge to snap the connector to for L and T connections.
maximum 1 element row
maximum 2 element rows
no
Do not snap the connector.

Other Seam Realization Options



Figure 20.
Option Action
row Specify how many rows of spring elements have to be created. The rows are parallel to the seam connector. The rows are distributes equidistant through the width.
width Specify the distance between the outermost element rows.

Final Connection to Link Entities Options

Input Action
mesh dependent/ mesh independent
Determine whether the realizations require a node connection.
mesh independent
For a realization which does not need any node connection and the connection is primarily defined via a solver-specific card or the nodes which need to be connected are defined by just a cylinder.
mesh dependent
All other cases.
adjust realization / adjust mesh
adjust realization
Adjust the realization itself, such as allowing non-normal realizations for the sake of locating nodes to create the realization.
adjust mesh
Adjust the mesh should locally (such as creating transition elements or remeshing) to ensure proper realization.
Note: Only available when mesh independent is selected.
quad transition / remesh Select a mesh adjustment method.
quad transition
Create quads to serve as a transition.
remesh
Remesh linked entities to achieve better links.
Note: Only available when mesh dependent and adjust mesh are selected.
imprint / skip imprint
imprint
Merge two meshes from two different link entities to create a transition mesh that matches up well with both.
skip imprint
Close-set connectors' transition quads may overlap and interfere with each other, causing one or more realizations to fail.
Note: Only available when mesh independent, adjust mesh, and quad transition are selected.
use pitch size to imprint / use avg. mesh size to imprint / size to imprint Select a method to determine the size of the imprint.
use pitch size to imprint
Use pitch size.
use avg. mesh size to imprint
Use the average size of the underlying mesh.
size to imprint
Specify a specific imprint size.
Note: Only available when mesh dependent, adjust mesh, and quad transition are selected.
find nearest nodes / project and find nodes / ensure projection Determine how the realization will adjust to locate nodes in the linked entities in order to establish links. This decision can be quite involved.
Note: Only available when adjust realization is selected.

Edit Subpanel Options

Table 1. Trim Options
Option Action
connector Select the seam connector that you would like to trim.
node Select the point that you would like to trim the connector at.
snap to connector point Trim the connector at specific points within a specified tolerance.
remove connector point
Remove the point the connector was trimmed at, along with any of its adjacent connector lines.
keep connector point
Trim the connector in a way that both connectors receive a connector point at the trimming position. All of the other connector points will remain at their exact, former positions.

By default this option is selected, and the tolerance is set to 1.0. If you clear this checkbox, connector points will be equally distributed when the connector is trimmed.

delete smaller connector piece Delete the smallest connector piece when the connector is trimmed.
trim Trim the connector into a new, unrealized connector. The new connector contain all of the information that was retained from the original connector.
Table 2. Params Options
Option Action
connectors Select connectors.
spacing/density
spacing
Distance between each weld location on the line.
density
Number of weld location on the line.
end offset / half spacing
end offset =
Offset first and last weld locations from the ends of the line by the end offset value.
half spacing
Offset by a value equal to half thee distance between weld locations.
Table 3. Group Options
Option Action
connectors Select connectors.
connect rule
group
Create one seam connector from each selected line, and group those seams which form a sequence of seam connectors together. Each group of connectors is then treated as a single connector entity. Each connector in the group has the same display mode, same realization state, and so on. Furthermore the start points and end points of two sequenced connectors in that group are treated as being one point. This fact allows this option also to be used together with realization types where the body element is positioned between the weld points, such as for all quad and hexa seam realizations. For hexa seams and for use of quad transition, the vertex angle has to be quite small to prevent bad hexa elements or imprint conflicts.
Note: The selected lines need to be longer than half the spacing length, otherwise the lines are ignored.
ungroup
Create one seam connector from each selected line. Even those seams which form a sequence of seam connectors are not grouped together. The start- and end- points of two sequenced connectors in that group are treated as being different points. This fact makes the use of quad transition impossible for sequenced seam connectors, because the imprint patterns will always conflict each other.
Note: The selected lines need to be longer than half the spacing length, otherwise the lines are ignored.

Seam Partitioning Options

Inputs Actions
connector Select the connector(s) that you wish to be partitioned.

Clicking partition updates the selected connectors with respect to the newly chosen settings. The connectors will become unrealized.

non-normal projection Clear this checkbox to consider only points with two valid "normal" projections as passed points during the partition.
Tip: This is the recommended setting, especially if the seam connector should be realized as a hexa row afterwards.
tolerance Use the given tolerance for the projection test and the newly created connectors.

Clear this checkbox to use the tolerance stored on each connector for both the projection test and the newly created connectors.

organize connectors with passed projections Select where to organize the newly created "passed" connectors.
default
Create a new component named CE_partition_passed, and organize all passed connectors in it.
current component
Organize the passed connectors into the current component.
original component
Organize the passed connectors into the same component that the original connectors came from.
component
Select an existing component to organize the passed connectors in.
number passed connector IDs Select how the newly created "passed" connectors are numbered.
start with
Specify a certain starting ID that the newly created "passed" connectors should be numbered from.
Preexisting IDs are blocked and skipped.
continue
Number the newly created "passed" connectors from the highest existing connector ID.
organize connectors with failed projections Select where to organize the newly created "failed" connectors.
default
Create a component named CE_partition_failed, and organize all "failed" connectors in it.
current component
Organize the failed connectors into the current component.
original component
Organize the failed connectors into the same component where the original connector came from.
component
Select an existing component to organize the failed connectors in.
number failed connectors IDs Select how the newly created "failed" connectors are numbered.
start with
Specify a certain starting ID that the newly created failed connectors should be numbered from.
Preexisting IDs are blocked and are skipped.
continue
Number all of the newly created failed connectors from the highest existing connector ID.
backup original connectors Select whether the original connectors should be backed up or not.
default
Create a component named CE_partition_backup, and organize copies of the original connectors into it, when the backup is activated.
Note: Any other name can be typed in and used as the default. A component with the specified name is created. It does not need to already exist (but see the next option).
component
Select an existing component to organize the backup connectors in.

Command Buttons

Button Action
group/ungroup Apply grouping or ungrouping to a set of connectors.
options Open the connector options panel where various settings can be defined.
edit Apply spacing, density, or offet changes to a connector.
create Create the connector(s) with provided input (if sufficient).
partition Apply the partitioning onto the selected connectors, using the provided input.
reject Undo the last action.
return Exit the seam panel.