CREATE PROPERTIES

 

In the eta/DYNAFORM, each drawbead carries its own property. Prior to creating the drawbead, the user must define the property accordingly. In the create property field, the NEW, EDIT, DELETE functions enable the user to create, modify and delete the property, respectively.

 

9.4.2.1    NEW PROPERTY

 

Click on the NEW button to display the DRAWBEAD PROPERTY dialog box as shown in Figure 9.4.2.

 

Figure 9.4.2 Drawbead properties dialog box

 

SECTION TITLE

Allow the user to name title for the property, the default title is bead1, bead2 and so on.

 

 

STATIC FRICTION COEF.

Allow the user to set the static coefficient of friction between the blank and the drawbead, the default static coefficient of friction is 0.1.

 

DYNAMIC FRICTION COEF.

Allow the user to set the dynamic coefficient of friction between the blank and the drawbead, the default dynamic coefficient of friction is 0. It means the dynamic friction between the blank and the drawbead is ignored.

 

BENDING LOAD CURVE ID

Allow the user to define the Fbending component of the drawbead restraining force. The Fbending component is referred as force per unit drawbead length as a function of displacementas illustrated in Figure 9.4.3.

 

NOTE: The NORMAL FORCE of drawbeads is set to 1.0e-6 automatically by eta/DYNAFORM. Hence, only the BENDING FORCE needs to be defined by the user.

 

Figure 9.4.3 Drawbead resisting force as a function of the drawbead displacement

The user can click on the  button to define the bending curve for the property using the DRAWBEAD LOAD CURVE dialog as illustrated in Figure 9.4.4. The user can select one of the curves in the list or select the NEW LOAD CURVE functions to generate drawbead force curve using one of the following two methods:

 

AUTO – This function enables the user to create bending curve according to the drawbead section figure and the material of the blank as illustrated in Figure 9.4.5. The user can input all the parameters in the DRAWBEAD FORCE PREDICTION dialog box, following by clicking on the OK button to exit the dialog box. The defined curve ID is specified as the BENDING curve ID for the property.

 

MANUAL – This function enables the user to manually create a bending curve for the property using the function in the dialog box as illustrated in Figure 9.4.6. Please refer Section 11.13 for detailed information about load curve definition.

Figure 9.4.4 Drawbead Load Curve dialog box

 

 

Figure 9.4.5 Drawbead Force Prediction dialog box

Figure 9.4.6 Define the Bending curve

 

FULL LOCK FORCE

This is an optional method to define the BENDING FORCE for the drawbead. If the checkbox is toggled on, the user can manually key in the FULL LOCK FORCE value in the input data field or click on the DEFAULT button to calculate the default full lock force. Then, the BENDING FORCE will calculate automatically according to the FULL LOCK FORCE.

 

NOTE: The default FULL LOCK FORCE is calculated by the material ultimate tensile strength and the thickness of the blank. The user has to define the blank material and properties prior to obtaining the default FULL LOCK FORCE.

 

DRAWBEAD DEPTH

Allow the user to define the depth of the drawbead, The default depth of drawbead is set as 1.0 (mm).

 

BENDING CURVE SCALE

Allow the user to set the scale factor for the BENDING CURVE. The default scale factor is set as 1.0 (or 100%).

 

After the user creates each new property, the new property is added to the property list and set as the current property.

 

9.4.2.2    MODIFY PROPERTY

 

This function enables the use to edit the current property.

9.4.2.3    DELETE PROPERTY

 

This function enables the use to remove the current property.

 

NOTE: The current property can be removed only if the current property is not assigned to any drawbead. Else, the following message is printed in the message prompt window:

 

THE PROPERTY ASSIGNED TO DRAWBEAD. CAN NOT BE DELETED.