Synchronized drive lathe systems are used when joining two (sometimes three) components that have a radial orientation. Two opposing spindles are coupled and driven at the same speed. This is accomplished with either a direct drive transmission, or electronically with synchronized motors and electronic gearing.

These machines can be constructed with the spindles in a vertical, horizontal, or inclined plane to optimize the effects on gravity on the weld pool.

Air and electrical utilities are available through the spindles via continuously rotating air unions and slip ring conductors. These utilities allow integration of automatic tooling with the machine controls.