Seam Rigid
This realization serves and realizes t-welds, lap-welds, and butt-welds at the same time.
Restriction: Available in Abaqus, LS-DYNA, Nastran, OptiStruct, and Radioss, and can
only be selected and defined in the Connector Entity Editor.
The weld type is identified automatically based on the orientation of the links to each other.
The dimensions and property for all heat affected zones (HAZ) can be defined
separately. An edge treatment can be defined for t-welds and butt-welds to move the
edge a precise distance from the opposite link.
General Info
- Weld Type
- Defines weather to setup a configuration exclusively for a T, L, or B connection, or automatically setup a configuration for each connection based on the angle.
- Tolerance
- Defines the distance from the connector location.
Weld Shape
- T Weld Shape
- Defines how the T weld is created.
- L Weld Shape
- Defines how the L weld is created.
- B Weld Shape
- B welds are always created in a straight manner.
Realization Details
The Realization Details settings position the yellow marked nodes in Figure 16,
Figure 17, and Figure 18.
The dimension of the welds are dependent on the Weld Shape settings.
- Dimensioning Scheme
- Defines the dimensioning scheme for the dimensions of the T weld, L
weld, and B weld connections.
- input
- Manually define discrete values for the weld dimensions, shown in black in Figure 16, Figure 17, and Figure 18, with the exception of thickness. The horizontal dimensions can be defined using a length or an angle.
- thickness dependent
- Choose a formula to define the weld dimensions, shown in black in Figure 16, Figure 17, and Figure 18, with the exception of thickness. The provided formulas are all dependent on the thicknesses t1 and t2. A formula can be chosen individually for each verticalV and horizontalH distance, or the same formula can be used for T, L and B.
- weldsize dependent
- Manually define discrete values for the weld dimensions, shown in red in Figure 16, Figure 17, and Figure 18. The verticalV and horizontalH distances are defined with formulas reflecting the weld sizes and the t1 and t2 thicknesses.
- DIM T (Dimensioning T)
-
Input Thickness dependent Weldsize dependent Horizontal Lengths LTH - by angle
- by length
- (t1+t2)/2
- 3*(t1+t2)/2
- t1+t2
t1/2+wh/2 (fix) Vertical Length LTV - by length
- by edge
- (t1+t2)/2
- 3*(t1+t2)/2
- t1+t2
- by edge
- t2/2+wv/2
- by edge
- DIM L (Dimensioning L)
-
Input Thickness dependent Weldsize dependent Horizontal Lengths LTH - by length
- by angle
- (t1+t2)/2
- 3*(t1+t2)/2
- t1+t2
wh/2 (fix) - DIM B (Dimensioning B)
-
Input Thickness dependent Weldsize dependent Lengths LB - by length
- by angle
- (t1+t2)/2
- 3*(t1+t2)/2
- t1+t2
- by edge
- wb
- by edges
- Edge Treatment (T/B)
- When discrete lengths are requested for T and B connections, it is sometimes necessary to move the edges.
- Max Length Value
- Defines the maximum length value.
Element Details
The DOF parameter controls the setting for the Degrees of Freedom for the RBE2 elements, which are created during the realization.
Connectivity Info
- imprint (default)
- Creates quad weld elements, and stitches them to both links by adjusting their mesh. All required HAZ are performed.
- skip imprint
- Creates quad weld elements, but does not change the meshes of the links. Instead, additional elements are created to represent the requested HAZ. These elements are organized in the ^conn_imprint component, and can later be used for a manual imprint after they have been manipulated to your needs. This option can be helpful when working with more complex areas, where the standard imprint functionality fails, for example, conflicting connectors.
- imprint/no HAZ
- Creates quad weld elements, and stitches them to both links by adjusting their mesh. Mesh modifications are as minimal as possible, and no HAZ are performed.
- none
- Creates quad weld elements only. Quad weld elements will not be attached to the links. The connection will need further attention.
HAZ Info
The HAZ Info settings define the lengths of the different heat affected zones (HAZ),
which are dependent on the HAZ lengths for T, L and B, defined in the Realization
Details parameters. The HAZ length settings vary depending on the defined weld
shapes (vertical, angled, vertical and angled, caps).
- HAZ Scheme
- Choose a dimensioning scheme for the HAZ lengths of T, L, and B.
- input
- Enables you to decide if the HAZ lengths should be defined individually, or if all HAZ lengths are determined using the same approach (same as all).
- weldsize dependent
- Only available if weldsize dependent has been chosen for the Dimensioning Scheme, as well.
- HAZ Lengths
-
- same as all
- Assigns the same length to all HAZ lengths.
- individual
- Assign HAZ lengths individually.
- Assign HAZ lengths individually
- The following options are available in the various HAZ length settings.
- input
- Requires a discrete value be specified for the length.
- average meshsize
- Length is dependent on the average mesh size in the local area where the imprint is performed.
- by thickness
- Sets the length to the same value as the thickness of the link getting the HAZ.
- LTH
- Horizontal length for T connections, which is the length between the foot points of the vertical and angled part of a seam.
- LLH
- Horizontal length for L connections, which is the length between the foot points of the vertical and angled part of a seam.
- LB
- Butt weld length.
- skip HAZ
- Skips individual HAZ that are not required.
- same as positive side
- Assigns the same length as the positive side to the negative side.
- wh or wh/2
- Length is dependent on the horizontal weld size. Only available when HAZ Scheme is set to weldsize dependent.
- wv or wv/2
- Length is dependent on the vertical weld size. Only available when HAZ Scheme is set to weldsize dependent.
- wb or wb/2
- Length is dependent on the butt weld size. Only available when HAZ Scheme is set to weldsize dependent.
- LTVedge
-
Choose between skip HAZ and LTVedge. Only available for the HAZTvedge length.
- HAZ Length Factor (Avg. Meshsize/Thickness)
- Factor that increases or decreases the HAZ lengths, which have been defined using the average meshsize or by thickness length options.
- Max HAZ Length
- Maximum length for all HAZ lengths. If the HAZ length is greater than this value, then the Max HAZ Length is used.
- Dimensioning T
-
- Dimensioning L
-
- Dimensioning B
Property and Material Info
The Property and Material Info settings define the properties and materials of the
welds and the heat affected zones (HAZ).
- HAZ Organize Scheme
- Choose a HAZ organize scheme:
- inherit property
- Inherits the elements of the HAZ from the links in which the HAZ elements are imprinted.
- general property
- Assigns the same HAZ property throughout one link, or throughout all links.
- individual property
- Assigns individual properties to each HAZ.
- HAZ Component Option
-
- stay in original
- Keeps HAZ elements in the component they were imprinted into. No additional properties get created.
- new component per original one
- Creates a new component for each component that gets a HAZ imprinted. The direct property assignment setting is ignored when this option is selected.
- HAZ Property Option
- The options available are dependent on the HAZ Organize Scheme selected.
- assign original property
- Assigns the same property that was assigned to the original components to new components.
- assign duplicated property
- Duplicates the original properties and assigns them to new components.
- select
- Select a property from the current model via the Select Property For HAZ option. Unless direct property assignment is activated, a component named ltb_rigid_quad_haz_ with the property ID as a postfix is created.
- same as original
- Assigns HAZ elements the same property as the original. No further properties are created. HAZ elements are organized into components named ltb_rigid_quad_haz_ with the property ID as postfix.
- scaled original thickness
- Creates a new property and component for each link that has a HAZ imprinted.
- input thickness
- Creates a new property and component for each link that has a HAZ imprinted.
- same as positive side
- Guarantees the HAZ on the positive and negative side of the T or L weld are assigned the same property.
- same as the other size
- Guarantees the HAZ on both sides of the B weld are assigned the same property.
- Direct Property Assignment
- When activated, additional components will not be created, and created or selected properties will be directly assigned to individual weld or HAZ elements.
Behavior
- B/L classification angle
- Angle that is automatically determined for each individual seam connector, whether it is to be considered a butt weld or a lap weld. Default is set to 10.0°.
- L/T classification angle
- Angle that is automatically determined for each individual seam connector, whether it is to be considered a lap weld or a t-weld. Default is set to 10.0°.
- Angle Direction
- Defines which side the angled weld elements are created.
- connector side
- Angled weld elements are created on the side where the connector is located, as long as the connector is not perfectly on the free edge.
- positive side/negative side
- The positive and negative side can be determined as long as the links are not perfectly perpendicular to each other.
- edge quad normal
-
- Snapping To Edge
- Automatic edge snapping can be used to precisely position connectors. First, the connector snaps to, for example, the closest free edge, then the projection and FE creation starts.
- Edge Treatment (T/B)
- The Edge Treatment(T/B) setting attempts to create specific vertical
lengths for T connections LTV, and specific lengths for B connections
LB.
- Edge Treatment Options
- Choose whether to:
- extension and contraction
- extension
- contraction
- Edge Treatment Limit
- Edge treatment is a pure node movement; therefore, the maximum movement needs to be limited to prevent the elements at the edge from being destroyed. Movement is limited to a maximum of 0.5 times the element size at the edge. 0.5 is the maximum allowed value and default value.
- Preserve Washer
- Controls how washers are preserved during the seam imprint
realization.
- Do Not Share Zone Elements
- Seam imprint allows heat affected zones (HAZ) to be merged in close areas. In this situation, one element might touch the weld elements from two different connectors. Do not share zone elements prevents zone elements from being shared.
- Quad in Corner
- Controls whether a single or double element is created in corners of quad seam connectors with a certain vertex.
- Quad Control
- Controls the maximum deviation from the perfect quad element for the heat affected zone (HAZ). It can be controlled, if the element size or the element skew is more important to retain.
- Max Quadsize Reduction In % / Max Quad Skew In Degrees
-
- Sliver Elements
- Sliver elements are small elements that you may not want in your model.
In the images below, a perfect perpendicular projection resulted in
sliver elements. The Sliver Elements setting can be used to manage
sliver elements in your model. In the images below, the red elements
represent the HAZ elements.
- Element length<
- This length controls which elements to treat as sliver elements.
- Feature Angle
- Determines important features to retain during the imprint. Features that cross the HAZ, as well as near by features cannot be retained.
- Seam Test Point Alignment
- A global option. If the seam connectors are close by activating “Seam test Points Alignment” option in connector entity editor, the test point alignment is based on the proximity of other connectors to get better mesh flow. It also ensures the cross-over connector should have a common test point, so that unique nodes will be created.
- Seam Loose Ends
- A local option set on individual connectors. Enabling “Seam Test Points Alignment” will also enable this option, which allows for the alignment of start and end points of seam connectors along with alignment of other test points.
- Seam Fixed
- A local option set on individual connectors. Enabling the “Seam Fixed” option considers all the test points of seam connectors as fixed and will not be disturbed.
- Seam Consider Feature and Boundaries
- A local option set on individual connectors. Enabling the "Seam Consider Feature and Boundaries" option will adjust test points so the projections fall on features/boundaries wherever possible. Overhanging test points will be trimmed.