Ceramic ferrules are attached around the stud tip on the welding gun. Stud welding ferrules are rings made from refractory ceramic materials. Interested in more information about our process or products? For use of ferrules, the following points must be observed. In this application the vents are only on one side of the ceramic ferrule to prevent molten steel from succumbing to gravity and running out the bottom. There are ferrules with. When a stranded wire is inserted into a terminal without a ferrule, several issues can arise: Loose Strands: The individual strands of the wire can spread out when inserted into a terminal, leading to poor contact, increased resistance, and potential overheating.