  In this paper we study welded knots and their invariants. We focus on
generating examples of non-trivial knotted ribbon tori as the tube of welded
knots that are obtained from classical knot diagrams by welding some of the
crossings. Non-triviality is shown by determining the fundamental group of the
concerned welded knot. Sample examples under consideration are the standard
diagrams of the family of $(2,q)$ torus knots and the twist knots. Standard
diagrams of knots from Rolfsen's tables with $6$ crossings are also discussed
which are not in the family of torus and twist knots.
