Cutting bit with split wear ring and method of making same

Abstract

The present invention provides a rotary cutting bit for use in road milling, mining and/or excavating applications that includes a split wear ring which is harder than the steel cutting bit body. The cutting bit has a cutting tip made of hard material such as tungsten carbide brazed into a nose portion of the steel tool body. The split wear ring is positioned in an annular channel in the tool body near the steel nose of the tool body. In one embodiment, the split wear ring is positioned so that the inner diameter of the split wear ring is smaller than the outer diameter of the cutting tip. Such a configuration allows the split wear ring to be tucked under the outer diameter of the cutting tip, decreasing tool body wear that could otherwise occur, thus providing longer tool life and reduced operating costs. The split wear ring pieces may be retained in place by a retainer such as banding rings, epoxies, tape or wire. Such retainers hold the ring sections in place during the assembly operation, so the ring sections do not move and remain attached to the tool body.