A weld-in sleeve is a cylindrical metal insert designed to be welded into a larger structure, often used to reinforce, repair, or adapt components in fabrication and mechanical assemblies. Commonly made from steel, stainless steel, or aluminum, weld-in sleeves are used in a wide range of industries including automotive, construction, and industrial equipment. They provide a durable interface for mounting hardware, joining dissimilar components, or strengthening areas that experience high stress or wear. The sleeve is typically inserted into a pre-drilled hole or over a mating part and then welded in place to ensure a secure, load-bearing connection. Proper material selection, fitment, and welding technique are essential to ensure the integrity and performance of the welded sleeve in its intended application.