First extract the unique part numbers, using Advanced Filter (Data Menu) to another area, say column F.

Once you have the unique parts in Column F, then in G2 enter formula:

=IFERROR(INDEX($B$2:$B$24,SMALL(IF($A$2:$A$24=$F2, ROW($A$2:$A$24)-MIN(ROW($A$2:$A$24))+1),COLUMNS($G1:G1))),"")

Adjust ranges to suit (don't use ranges larger than necessary).

Then confirm the formula with CTRL+SHIFT+ENTER not just ENTER.

Copied down and across as far as needed to get all the data.