Big Part Machining: Overcoming the Forces of Nature
Successfully machining big parts can highlight man’s ability to overcome the forces of nature in a way that few other achievements can. The recent imX event in Las Vegas featured metalworking industry suppliers presenting process solutions and unique information about their capabilities that helped the audience better understand their strengths.
When I sat in at a Seco Tools presentation, I learned about some of its unusual cutting tool developments and applications. One speaker I found particularly interesting was Seco Tools customer Neville Withers of Iljin America (Greer, South Carolina). He talked about the development of custom tooling for machining 10- and 13-foot-diameter yaw and pitch gears for wind turbines.
In this wind turbine assembly, the light blue pitch bearing assembly (No. 1) is mounted to the rotor hub. The darker blue yaw bearing (No. 2) is mounted between the nacelle and tower.
No doubt, the technical aspect of designing and building this tooling tapped Seco Tools’ engineering abilities. However, during Mr. Withers’ presentation, he emphasized a less-tangible attribute better known as “whatever it takes.”
One weekend, while working under severe time constraints, Seco Tools and Iljin America personnel were able to identify and remedy another supplier’s cutter performance problems. They were able to build a new, custom holder equipped with carbide inserts designed to efficiently cut especially large gears made from low-alloy chromium molybdenum steel. They overcame challenges such as component cross-section susceptibility to warping and twisting due to sub-optimal cutter geometry and toolpath strategy. They also solved a chip evacuation problem that could prevent acceptable surface-finish conditions in the gear tooth profile.
A smiling Mr. Withers stands inside one of the machined yaw gears, a testament to the success of these companies at overcoming the forces of nature by working together.