Rail re-profiling method and apparatus

A method of milling a profile of a railway rail in situ comprising:

• rotating, about a rotation axis, a milling cutter including a plurality of face mounted cutting inserts mounted about a periphery of the milling cutter, each cutting insert including a respective cutting edge having a respective radially outer end and a respective radially inner end;
• milling a facet along the railway rail in situ with the cutting edges rotating in a predetermined plane corresponding to at least a portion of a desired rail profile while controlling a depth of cut of the cutting inserts;
• longitudinally traversing the railway rail with the milling cutter while milling the railway rail;
• and
• controlling the speed of traverse of the milling cutter along the railway rail;
• wherein the facet has an interior longitudinal edge proximal to the rotation axis of the milling cutter, and has an exterior longitudinal edge distal from the rotation axis of the milling cutter;
• wherein for each complete rotation of the milling cutter about the rotation axis, (i) the radially outer end of the cutting edge of a given one of the cutting inserts enters the facet a first time and a second time and exits the facet a first time and a second time, respectively, and (ii) the radially inner end of the cutting edge of the given one of the cutting inserts enters the facet for a first time and a second time and exits the facet for a first time and a second time, respectively;
• wherein an included angle formed in a plane of a top surface of the railway rail and between the cutting edge of the given one of the cutting inserts and the exterior longitudinal edge of the facet at a point on the exterior longitudinal edge of the facet where the radially outer end of the cutting edge of the given one of the cutting inserts exits the facet for the first time as the milling cutter rotates about the rotation axis is 25° to 50°.