I want to know, if it is possible that dimensions of same thickness rectangle parts in an assembly, is added in B.O.M table automatically.
What you need to do is :
1. name your dimensions commonly (for convenience).
2. Create commonly named custom properties (necessary this time) and direct sw to look for the dimension using the previously assigned dimension names as part of the pointer.
So far we've been working on the part level.
Now we'll create a bom from a drawing view or a general table based on the drawing's referenced file.
3. RMB one of the column headers and insert a Column. From the drop down menus select the property you have created
Just so you know this type of process can be optimized to the point where more time is spent in setting up than you could make up for if this isn't a workflow that is used very often.
Some small things that can be done quickly though include creating custom properties using the custom property tab builder and using design tables for part creation to have your dims. named and organized from the get go.