February 1, 2010
Pushing durable tools to their limits may be routine in turning standard metals, but Cutting Tools Chicago along with Ingersoll Cutting Tools, the practice works for improving efficiency when cutting high temperature alloys such as Inconels, Waspalloys, and others. Gains in cutting tool edge life and faster operations save the company $70,000 per year in turning costs alone.
Jeff Hogya, former engineer and now Ingersoll Cutting Tools employee, contends “when turning tough to machine metal, shops shouldn’t be so dazzled by longer edge life that they forget to push material removal rates.
Machining profit comes more from saving time than preserving edges.” This is why during an assignment at Slabe to improve turning efficiency on high temperature alloys; he chose five of the shop’s highest volume jobs to test several available cutters before selecting Ingersoll’s TaeguTec tooling.
The first test involved a 1.560 inch long cut turned a 175 sfm and 0.008 ipr in a Waspalloy stator part. Edge life increased from two pieces to twelve, and raising the cutting rate to 185 sfm and 0.009 ipr only dropped edge life to 10 pieces. This still produced a total five fold gain in edge life and a 12% increase in throughput.
On the second test piece, and Inconel 718 anti-rotation lug with a 2.180 inch long cut, turning at 165 sfm and 0.007 ipr boosted edge life from seven to 27 parts. Cranking up to 175 sfm and 0.008 ipr generated a 13% increase in throughput with an edge life of 25 parts.
For another Waspalloy part with a 1.560 in long cut, roughing at 155 sfm and 0.0065 ipr with the Ingersoll cutter increased edge life from 15 to 24 pieces, and finishing at 165 sfm and 0.003 ipr upped life from 15 to 50. Slabe couldn’t raise the cutting rate any higher for this part because it was a two spindle operation and the other spindle governed cycle time.
The fourth test part, an Inconel 718 turbine component with a 3.280 inch long cut, experienced increased edge life from six to ten pieces during roughing and 10 to 40 for finishing. Finishing, originally ran at 165 sfm and 0.002 ipr, rose to 180 sfm and 0.003 ipr at a 0.008 inch depth of cut for a 60% gain in throughput — stemming from shorter cycles and fewer stops to index.
The fifth test job ran on a Citizen M 32 Swiss type machine and involved an Inconel 718 pin with a 0.625 inch long cut. Edge life jumped from 10 to 45 pieces per edge, significant because the machine took five minutes to index.