ABSTRACT

Figure 6.3 Contour inspection results for hemishell workpieces (courtesy of Martin Marietta Energy Systems, Inc.).

by each group of parts was approximately the same. However, the baseline coolant temperature for the control group varied about the nominal room temperature while the temperature of the other group varied about a point that was three degrees higher. The result was that the machine with the higher temperature cutting fluid was being periodically subjected to an intermittent thermal shock that was causing a degradation of its dimensional stability. From the inspection results, it is readily apparent that the lack of control of the coolant temperature had a negative effect on workpiece quality, and that this parameter is a prime candidate for being monitored and/or controlled.