Grinding Journal - Fall 2007 - (Page 15)

Compounding manufacturing difficulty is the hightolerance and complex nature of many superalloy components. The shape of the parts often makes them difficult to hold securely for machining. Finally, both the alloys and the parts they comprise usually are very expensive. Grinding offers advantages for finishing operations Progress continues in productive rough turning and milling of superalloys, but for finishing operations grinding is generally the process of choice. Although grinding is often thought of as expensive, dirty, and relatively slow, it offers a number of clear benefits when handling superalloys. Grinding processes can be customized to precisely match part requirements. Varying the size of the wheel’s abrasive grains provides control of cutting forces and surface finish. The porosity of the grinding wheel can be manipulated to promote the flow of coolant into the cut and speed evacuation of chips. Diamond dressing enables the formation of highly accurate wheel shapes to produce complex part geometries meeting tolerances of 0.0001" or better. Continual wheel dressing enables process control that is not possible with a cutting tool that becomes duller with each successive cut. Today’s grinding machines themselves feature a variety of productivityboosting systems including process monitoring and automatic loading that further enhance productivity. Metal removal rates achieved with modern grinding techniques can be relatively high, providing an economical way to process superalloy parts compared to EDM and other techniques. Superalloys are commonly used in turbine parts that operate at temperatures from 1,500 to 2,400° F. Vanes Shrouds Blades Disks Turbine illustration courtesy Pratt & Whitney Grinding Journal 15

Table of Contents Feed for the Digital Edition of Grinding Journal - Fall 2007

Grinding Journal - Fall 2007 Contents From Virginia: Apparently no credit crunch for machine tools Why measure cutting tools Other perspectives on CNC tool measuring Productive grinding of superalloys SUPER service grinding BIG rolls Problem Solver

Grinding Journal - Fall 2007

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.