NDE and Design — A Unified Life-Cycle Engineering Approach

Abstract

INTRODUCfIONUnified life-cycle engineering (ULCE) is an approach that combines aspects of concurrent engineering, total quality management, and retirement-for-cause (RFC) strategies at the early design stage of components [1][2][3]. In order to implement ULCE approaches, inspectability, reliability, and the other "ilities" of Fig. 1 must be linked to areas such as qUality assurance, life-cycle costs, and materials and processes in a comprehensive design environment.NDE models can provide one of the key ingredients for the design environment of Fig. 1 because of their ability to be used for in-process control of important parameters in the manufacturing process, their role in process automation, and the ability of such models to consider in-service issues. Such models are also the foundation for other models involving reliability, life-cycle costs, etc.Recently, significant progress has been made in establishing such NDE models as well as building the other links of Fig. 1 through the joint National Institute of Standards and Technology/Iowa State University/Northwestern University program in Integrated Design, NDE, and the Manufacturing Sciences. Here, we will describe the types of NDE and reliability models that have been built in the program and how they fit with the other ULCE elements shown in Fig. 1 to produce a new engineering technology for incorporating inspectability into a concurrent engineering design process. NDE MEASUREMENT MODELSOne of the major accomplishments of the NIST/ISU/NU program has been the development of comprehensive models of NDE inspections and the integration of those models into the design environment. These models are all based on the fundamental physics of these NDE measurement processes, so we refer to the models as NDE measurement models.

Evolution of Qnde’s Core Interdisciplinary Science and Engineering Base

“…• It is important to re-establish the Unified Life Cycle Engineering (ULCE) activity that the Air Force initiated some time ago [63,64,65]. This concept, shown anecdotely in Fig.…”

Probability of Detection (POD) for Nondestructive Evaluation (NDE)

“…In 1993, Schmerr and Thompson (1993) expanded on the concept of POD models integrated into a unified life cycle engineering approach that was earlier reported by Gray, et al Figure 4-11 shows the elements of a design environment that includes CAD, stress and materials analysis, NDE inspectability estimates (POD), and reliability calculations that are coupled together to form a new concurrent engineering design technology. These unified life cycle engineering approaches that incorporate POD modeling capability were also reported by Wormley, et al (1993 (Rajesh, et al, 1991 and Figure 4-11 A general Unified Life Cycle Engineering Environment Thompson and Schraerr continued their efforts to describe the development and uses of model-based probability of detection curves in a 1993 review paper .…”

“…In 1994, Schmerr and Thompson (1994) presented an updated review of efforts to develop a unified life-cycle engineering approach that was based, in part on the growing capability to model NDE performance. The authors concluded that this is leading to a new technology that will allow NDE to be fully integrated in design and life cycle performance.…”