Pull reamer
AssigneeKennametal Inc.
InventorUwe Hobohm
Life of this patent
Estimating the term…
Abstract
In order to allow high-precision machining of the inner surface of a pipe using little machining time, the draw broach has a cutting part having a plurality of cutters extending in the axial draw direction. The cutting part is divided into a main part and an insertion part tapering conically in the draw direction. The insertion part in turn is divided into a front region, viewed in the draw direction, forming a pre-cutting stage, and a rear region, wherein the conicity of the pre-cutting stage is less than that of the rear region.
Claims14
A pull reamer for machining the inner surface of a tube, comprising a cylindrical shank part having a diameter adapted to receive a pulling tool and a blade part having a plurality of blades extending in an axial pull direction, wherein the blade part has diameters greater than the shank part and wherein the axial pull direction is the direction in which the pull reamer is pulled through the tube, wherein the blade part is subdivided into a main part and an entry part, wherein the entry part tapers conically in the axial pull direction, wherein the entry part forms a roughing stage on a front region as viewed in the axial pull direction and a rear region is directly adjacent thereto and forms an uninterrupted connection therewith, said roughing stage having smaller conicity than a rear region of the entry part, wherein the roughing stage is virtually cylindrical.
Dependencies are inferred from the claim text.