A cursor is not the right approach for this scenario. Allthough it is not very clear what your situation is, it sounds like you can just insert the results from two tables joind together into a new table.
Table_A holds the company, plant, part, etc. values
Table_B holds the 'from part', 'to part', and maybe some more relevant columns
The query would look like this:
SELECT {specify the required columns here}
INTO {new_table}
FROM Table_A
INNER JOIN Table_B
ON Table_A.part = Table_B.from_part