Whats the difference between overlap welds and butt welds on reinforced urethane belts?
You can easily see the difference between an overlap weld and a butt weld. An overlap weld usually has a big 2″ long bump at the joint where the reinforcing cords are overlapped, whereas a butt weld is just a thin line circling the belt. Overlap splices can last a little longer than butt welds if they are perfectly made, but it is hard to make perfect overlaps. A thick layer of urethane must surround each cord. If the two cords touch each other, or if one cord is too close to the surface, the cord pulls out and the belt stretches prematurely. Trying to make perfect overlap welds often produces quite a few rejects, so the price must be higher than for butt welds. (see next question).
