Configuring Session Time-out
To configure a session timeout:
1. Browse to C:\Program Files (x86)\PTC\Windchill Risk and Reliability 12.0\Web folder.
2. Open the web.config file.
3. Update the following with the required timeout:
<forms name=".ASPXFORM" protection="All" path="/" timeout="30"/>
* 
The default value for session timeout is 30 mins.