The advantages of creep feed grinding are shorter machining times, lower surface roughness, improved profile, and dimensional accuracy [Minke and Tawakoli 1991]. In industrial mass production, there are two fields of application of creep feed grinding in which high cutting performance and high component quality are required. In mass production, creep feed grinding is used to grind deep grooves with mostly parallel side walls and profiles in tight and deep profile contours and/or for difficult-to-grind materials. In the case of rotor manufacture, up to 30-mm deep slots are ground into the solid, mainly hardened material. A second field of application for creep feed grinding is turbine blade manufacture from nickel-base superalloys. In the case of these workpieces with different profiles, high requirements are placed on geometrical accuracy and surface quality. Moreover, highest demands are made on the absence of heat-influenced workpiece subsurface layers. Creep feed grinding satisfies these work conditions concerning high removal rates and surface quality within the limitations of quickly rising contact zone temperatures [Werner and Minke 1981].
16.3.4 Economics of Creep Feed Grinding
Lower grinding times and high achievable surface quality with a high removal rate argue for creep feed grinding in contrast to reciprocating grinding. In the range of medium to high batches, creep feed grinding is, therefore, more cost-efficient than reciprocating grinding. Grinding machines and ancillary units tend to be expensive resulting from higher thermal, statical, and dynamic stresses and consequent requirements for special machine designs.
The choice of adequate grinding machines is a crucial prerequisite to completely utilize the potential of creep feed grinding. Requirements for economic creep feed grinding of ceramics are as follows [Uhlmann 1994a]:
• High process forces require static and dynamic rigidity, high spindle drive performance, load-independent rotational speed.
• High process temperatures and large contact lengths require cooling lubricant pumps with increased volume flow and pressure, adapted cooling lubricant nozzles.
• High-dimensional accuracy and high forces require high-precision and rigid bearings and guidances, shock-free and precise drives.
• High concentricity and adjustable grinding wheel topography require integrated auxiliary conditioning equipment for diamond grinding wheels.