to AsTM standard practices were rigorously followed. Subsequent investigation and analysis of the indications revealed no growth of the laps in service. Nevertheless, the corrective action defined that all forgings showing laps be removed from service. Preventive measures involved critical review and revision of the forging process(so that future lots would be properly forged) and revisions to the nondestructive evaluation (NDE) procedures at the forging supplier Building an application-life diagram around this case(Fig. 20)(Ref 29), one can explore the impact of material defects of various sizes on service life. In one possible scenario, the lower curve in Fig. 20 could describe the observed lap, being detectable by nDe and of a size sufficient to sustain growth under the anticipated service conditions at some time in the future. However, at the time of the inspection, the defect was smaller than that required for crack growth, since the date of the inspection is relatively early in the intended service life of the component. The risk of crack growth and premature failure at some time in the future (as shown by the"X"in Fig. 20) prompted the removal from service of all forgings showing NDE indications Flaw smaller than NDE detectability (required) efect smaller than size required for growth Anticipated severty I Defect larger than size required for growth Increasing service life Inspection date Intended life Fig 20 Application -life diagram showing effects of different sized material discontinuities on service life Manufacturing/Installation Defects Manufacture refers to the process of creating a product from technical documentation and raw materials, generally performed at a factory. Installation can be considered manufacturing in-place, such as at a construction site or a new plant. Products can be designed properly using sound materials of construction, yet be defective as delivered from the manufacturer, due to rejectable imperfections (i.e, defects)introduced during the manufacturing process or due to errors in the installation of a system at a site. A wide variety of manufacturing- caused defects exist; each and every manufacturing/installation process has many variables that, when allowed to drift toward or to exceed control limits, can result in a defective product(Ref 34) Some examples of such manufacturing/installation anomalies are listed below(Ref 35, 36). Failures associated with metalworking, welding, and heat treating operations are also discussed in more detail in other articles in this Volume, and example 4 also illustrates the effects of manufacturing anomalies on the life of a component Metal removal processes Cracks due to abusive machining Chatter or checking due to speeds and feeds Thefileisdownloadedfromwww.bzfxw.comto ASTM standard practices were rigorously followed. Subsequent investigation and analysis of the indications revealed no growth of the laps in service. Nevertheless, the corrective action defined that all forgings showing laps be removed from service. Preventive measures involved critical review and revision of the forging process (so that future lots would be properly forged) and revisions to the nondestructive evaluation (NDE) procedures at the forging supplier. Building an application-life diagram around this case (Fig. 20) (Ref 29), one can explore the impact of material defects of various sizes on service life. In one possible scenario, the lower curve in Fig. 20 could describe the observed lap, being detectable by NDE and of a size sufficient to sustain growth under the anticipated service conditions at some time in the future. However, at the time of the inspection, the defect was smaller than that required for crack growth, since the date of the inspection is relatively early in the intended service life of the component. The risk of crack growth and premature failure at some time in the future (as shown by the “X” in Fig. 20) prompted the removal from service of all forgings showing NDE indications. Fig. 20 Application-life diagram showing effects of different sized material discontinuities on service life Manufacturing/Installation Defects Manufacture refers to the process of creating a product from technical documentation and raw materials, generally performed at a factory. Installation can be considered manufacturing in-place, such as at a construction site or a new plant. Products can be designed properly using sound materials of construction, yet be defective as delivered from the manufacturer, due to rejectable imperfections (i.e., defects) introduced during the manufacturing process or due to errors in the installation of a system at a site. A wide variety of manufacturing-caused defects exist; each and every manufacturing/installation process has many variables that, when allowed to drift toward or to exceed control limits, can result in a defective product (Ref 34). Some examples of such manufacturing/installation anomalies are listed below (Ref 35, 36). Failures associated with metalworking, welding, and heat treating operations are also discussed in more detail in other articles in this Volume, and example 4 also illustrates the effects of manufacturing anomalies on the life of a component. Metal Removal Processes · Cracks due to abusive machining · Chatter or checking due to speeds and feeds The file is downloaded from www.bzfxw.com