disk - saw

Century Dictionary and Cyclopedia

1. n. A saw in the form of disk, used for cutting rails or beams in the rolling-mill. Its cutting rim is either toothed or toothless. It is set in rapid rotation and the friction of the contact produces a heat sufficient to fuse the metal in contact with the disk as it revolves, even if the disk is softer in quality than the metal to be sawed. Also called fusion-disk.