Getting Started with the Process Capability Database
The Process Capability Database (PCDB) is an internal database within 3DCS Variation Analyst Version 7.3. It allows users to create specific tolerance values and then link them to a tolerance in a 3DCS model.
In this Tips and Tactics, we will go over how to add, create and edit the Database, and how to add a link to a tolerance from the DB.
In 7.3, the Process Capability Database (PCDB) has brought a variety of new functions to 3DCS.
Here’s a short list:
- New PCDB editor: Edit, create and/or delete tolerances in Excel or the internal PCDB editor.
- Faster and easier tolerance creation with additional tools linking to the PCDB
- Added Help, Summary, and Editor buttons
- Two new displays for Linked or Broken tolerances; from the PCDB to the model
- Added a Browse icon to import created PCDB files (.csv)
This is an example of a PCDB .csv file. There are a couple of things to note here before we get into creating the database file.
- The portion above applied tolerances is necessary for the Process Capability DB to take the file.
- +-3STD_Value is the actual Range Value. The column lists as 0.00E-00 but when edited, the user can add 0.25 for the range value, it will show as 2.5E-01.
- The RAN_NUM can only have values of 1, 2 and 4, corresponding to the type of tolerance. For example: a Composite Position tolerance will have 4 Rand# available.
Accessing the Process Capability Database in CATIA V5 and Multi-CAD
Accessing in 3DCS CATIA V5
To access Process Capability Database in CATIA V5, go to the 3DCS menu item select Data from the drop down and find Process Capability DB.
Accessing in 3DCS Multi-CAD
To access Process Capability Database in 3DCS Multi-CAD, go to the Tools drop down menu and select Process Capability DB.
What If I Don't Have a Database Yet?
If there isn't a current database file (in .csv format), and you'd like to add one, start by clicking the Go to DB Editor button after selecting the Process Capability DB in the previous step.
The Database Editor
Step 1. Right-click on the top line; the Database file. The menu displayed to the right will appear.
- To create a new Database file, you will need to select Create Default DB…
- Right-click the top line again and select Save As… This will create a CSV file with one default, editable tolerance.
- Right-click the top line again and select View in CSV Editor…
Step 2. An excel spreadsheet in .csv format will come up. You can edit the process tolerances here (the first one set to dcsProcItem1 as default), including the name, range (+/-3 STD) and offset value.
After adding tolerances, make sure to save the file in .csv format and close out of Excel.
Step 3. (Above image) In the Database UI, select the “…” browse icon and select the previously saved CSV file.
Step 4. (Below image) Select Load DB and Show Link Info. This will load the CSV file into 3DCS and show linked and non-linked tolerances in the model.
Step 5. Edit or create a tolerance.
Step 6. Select the Link to DB button. The Database Link to Random list will appear.
Step 7. Double-click an item in the list to link to the tolerance. The range and offset are automatically updated.
If a tolerance value needs to be changed, the user can reopen the .csv file linked to the 3DCS model, change the values and update the DB in the model. The tolerance will update through the model.
Alternatively, the user can right-click on point(s) or feature(s) and select Add Tolerance. This will start the PCDB Link to Random dialog. By selecting a tolerance from the list, a new tolerance will be created with the selected points or features. The tolerance will be linked to the PCDB and automatically update the range, offset, tolerance name and feature/point list.
Looking for more on the Process Capability Database?
Click here to view the video introduction to the Process Capability Database