1. Studs with a thread engagement length of bm = 1d are typically used for connections between two steel components; studs with bm = 1.25d and bm = 1.5d are generally used for connections between cast iron components and steel components; and studs with bm = 2d are typically used for connections between aluminum alloy components and steel components. In the aforementioned scenarios, the first component features a tapped (internally threaded) hole, while the second component features a through-hole.
2. Equal-length studs require threads at both ends to engage with nuts and washers; they are used to connect two components, both of which feature through-holes. A weld stud is welded at one end to the surface of a component; its other end (the threaded end) passes through a second component that features a through-hole, after which a washer is applied and a nut is tightened to join the two components into a single integral assembly.
3. A weld stud is welded at one end to the surface of a component; its other end (the threaded end) passes through a second component that features a through-hole, after which a washer is applied and a nut is tightened to join the two components into a single integral assembly.