| 摘要 |
<p>There is described a casing cutter of the type having a pivotable milling arm (10) which pivots outwards to trace a substantially conical path during rotation of the cutter. The milling arm is provided with an effective cutting edge (18, 20) which has an offset with respect to a notional axial reference line of the arm which passes through the pivot axis of the arm. The offset of each cutting edge is a distinct combination of circumferential offset and radial offset from the notional axial reference line so that a different effective cutting edge is presented to the casing to be cut when the cutter is used to cut a plurality of concentric casings of different diameters.</p> |
