Creating a Bearing Load

Bearing Loads are simulated contact loads applied to cylindrical parts.

This capability is only available if you installed the ELFINI Structural Analysis product.

Creating Bearing Loads is done in only one step and is much quicker than creating first a virtual part and then a load. Computation is also much less time-consuming, because Bearing Loads do not generate either costly contact beam elements or virtual mesh parts.

The user selects a cylindrical boundary of the part. Any type of revolution surface can be selected. In the Bearing Load definition panel, you have to specify the resulting contact force (direction and norm). The components of the force can be given either in the global or in a user axis system (similar to the Distributed Force).

Bearing Loads are flexible: You can vary the angle sector on which the force is applied as well as the type of the profile distribution.

Display of the applied sinusoidal traction:

Bearing Loads objects belong to Loads objects sets.

Bearing Loads can be applied to the following types of Supports:

Mechanical Feature	Geometrical Feature				Analysis Feature
Mechanical Feature	Point or Vertex	Curve or Edge	Surface or Face	Volume or Part	Analysis Feature
			Cylindrical surface

This task shows you how to create a Bearing Load applied to a selected geometry.

You can use the sample02.CATAnalysis document from the samples directory for this task.

Before You Begin:
Go to View -> Render Style -> Customize View and make sure the Shading, Outlines and Materials options are active in the Custom View Modes dialog box.

1. Click the Bearing Load icon

.
The Bearing Load dialog box is displayed.

2. You can change the identifier of the Bearing Load by editing the Name field.

	The `Axis System Type` combo box allows you to choose between `Global` and `User` Axis systems, for entering components of the resultant force vector. `Global`: if you select the `Global` Axis system, the components of the resultant force vector will be interpreted as relative to the fixed global rectangular coordinate system. `User`: if you select a `User` Axis system, the components of the resultant force vector will be interpreted as relative to the specified rectangular coordinate system. To select a `User` Axis system, you must activate an existing Axis by clicking it in the specification tree. Its name will then be automatically displayed in the `Current Axis` field. Only the Force vector component which is perpendicular to the revolution axis is taken into account because this component is a contact component.
	The `Angle` value corresponds to the angle over which the forces can be distributed. When entering an angle value, a highly precise preview automatically appears on the model. `180` is the default value, `< 180` is useful to take into account some positive clearance, `> 180` is useful to take into account some negative clearance.
	The `Orientation` option provides you with two ways for distributing forces:

Radial: all the force vectors at the mesh nodes are normal to the surface in all points. This is generally used for force contact.
Parallel: all the force vectors at the mesh nodes are parallel to the resulting force vectors. This can useful in the case of specific loads.

Radial:

Parallel:

The profile type can be Sinusoidal, Parabolic or Law type, defining how you will vary the Force intensity according to the angle: Sinusoidal,Parabolic or Law.
Law: or F=f(q) requires that a formal law (Formal parameters) was defined in Knowledge Advisor (Fog). On the condition you previously activated the Relations option in Tools -> Options -> Part Design (Display tab) command, you can see the Law feature in the specification tree. No sooner do you select this feature in the specification tree, that this formal parameter appears in the Law field (Bearing Load dialog box).

You can define the resultant force vector direction by using the compass.
You can modify the compass orientation either with the mouse or by editing the compass.
By applying the compass to any part geometry, you can align the compass directions with the implicit axis directions of that geometry: drag the compass by handling the red square and drop it on the appropriate surface. The normal direction to this surface defines the new direction. Then, click on the Compass Direction button to take this new direction into account. You can now invert the direction if desired, editing the values of the three components.

3. Set the Axis system to Global.

4. Enter values for the X, Y, Z components of the resultant force vector. For example, X = -500N.
The corresponding Norm value is automatically computed and displayed.

5. Set the Angle value to 90deg.

6. Select the support ( a geometry) on which the resultant Bearing Load vectors are applied. Any selectable geometry is highlighted when you pass the cursor over it.

Selected support:

Resultant load:

7. Click OK Bearing Load dialog box to create the Bearing Load.
A Bearing Load object appears in the specification tree under the active Loads objects set.

	You can either select the support and then set the Bearing Load specifications, or set the Bearing Load specifications and then select the support.
	If you select several geometric supports, you can create as many Bearing Loads as desired with the same dialog box. A series of Bearing Loads can therefore be created quickly.
	Loads are required for Stress Analysis computations.
	If several Analysis Cases have been defined in the Finite Element Model, you must activate a Loads objects set in the specification tree before creating a Bearing Load object.
	Bearing Load objects can be edited by a double click on the corresponding object or icon in the specification tree.

Make sure the computation is finished before starting any of the following operations.

Products Available in Analysis Workbench

The ELFINI Structural Analysis product offers the following additional features with a right mouse click (key 3):

on a Bearing Load object:

Bearing Load Visualization on Mesh: the translation of the Bearing Load specifications into solver specifications can be visualized symbolically at the impacted mesh nodes, provided the mesh has been previously generated via a Compute action.

on a Loads objects set:

1) Generate Image: generates an image of the computed Load objects (along with translating all user-defined Loads specs into explicit solver commands on mesh entities), by generating symbols for the elementary loads imposed by the Loads objects set. The image can be edited to include part or all of the options available.

2) Report: the partial status and results of intermediate pre-processor computations are reported in HTML format. It represents a subset of the global Report capability and generates a partial report of the Loads objects set Computation.

See Creating Pressures for more details.

3) Double-clicking on the Loads set, you will display the Loads dialog box that lets you choose whether you wish to apply self-balancing to the load. Example of use: if this option is used with iso-static specifications, it will allow you to simulate free-body loading. If you make the option active, the center of inertia results null.