Creating a Web Girder

This task explains creation of a web girder or bracket. The process is essentially the same as that of creating a transverse bulkhead, with the important differences that a web girder or bracket is limited by objects, and a sketch (which is a free edge).
The process of creating a web girder or bracket is the same, with a difference that is explained below. This task explains the steps needed to created a web girder. The same steps can be used to create a bracket.

 

1. Create an SFD system under the tertiary system (see Organizing Your Document), rename it if necessary. Select the CATPart that is created under the system in the specifications tree and go Start - Equipment & Systems - Structure Discipline - Structure Detail Object Design.  The image below shows finished web girders (highlighted at the lower part of the image), along with the specifications tree structure.

 

2.

Click the Plate button to display the Plate dialog box. The entries are explained below:

  3. CATEGORY: Click on the down arrow to display the entries - they will include the last 10 entries that you selected. If Transverse Bulkhead is not displayed then select More to display the Class Browser and make your selection from that list.

NOTE FOR BRACKETS: If you are creating a bracket then select Other in the Category field. This allows the bracket to be at any angle, and the molded conventions are not applied. Bulkheads are limited to an incline of not more than 45 degrees.

  4. NAME: The application can assign a name to the object you are creating using the object naming function if you check the Automatic checkbox. If you want to assign your own name then uncheck the box and enter a name.
  5. SUPPORT: Select a cross as the location for the bulkhead -  once you select a cross the bulkhead is placed (in preview mode). Your selection displays in the Support field.
  6. LIMITS: This function trims the excess plate.

To do this, select under Limits, and select the objects you want to use to limit the web girder. (In this example, shell and upper and lower deck.)

The plate is trimmed, and the Object field displays the objects you selected.

The image below shows the trimmed web girder. The fourth side is not yet trimmed.

Under Offset, you can define the offset value of each plate limit. A positive value adds material. A negative value removes material. Additionally, limit tags display in your 3-D session to assist with plate limit management.

The Remove button allows you to delete a limit.

The Switch Side button lets you toggle between limited sides. You can also switch sides by selecting the same limit again.

  7. Click the Sketcher button . The Sketcher application opens with the support object selected as the sketch plane. However, it may not be visible because of the hull structure, in which case click the Cut Part by Sketch Plane button to make it visible. Use one of the Sketcher tools to draw a 'limit' to the web girder. The image below shows part of the hull and the web girder, with a line drawn at the location where it will be limited.

  8. Exit the Sketcher. The web girder will be limited at the line you drew.
  9. To place more than one web girder, select the Support field again and select your supports - in this case the planes. The web girders will be placed with the same limits used in placing the first one.
  10. Click OK when you have finished.